Predicted grasshopper development

The oviposition index provides a snapshot of how growing season conditions impact grasshopper development and subsequent oviposition. Advanced development of the current generation will result in greater potential egg production by females at the end of this growing season. Figure 1 represents model output for the 2020 growing season (as of August 17, 2020). In Alberta, cooler, wetter conditions in May and June were not conducive for grasshopper development. This has resulted in a prediction for lower oviposition potential for most of Alberta. Warmer, dryer conditions in Manitoba and southeastern Saskatchewan resulted in higher oviposition indices.

This image has an empty alt attribute; its file name is 2020Aug10_Msang_OvipositIndex.png
Figure 1. Predicted oviposition for (Melanoplus sanguinipes) populations across the Canadian prairies (as of August 17, 2020).

The model was run with climate normal data to compare the 2020 growing season with 30 year climate normals. The second map (climate normal) indicates that, in an average growing season, the greatest oviposition index values are observed for southeast Alberta and southwest Saskatchewan (Figure 2). Results suggest that the 2020 growing season was more favourable for grasshopper populations in Manitoba and southeastern Saskatchewan than for western Saskatchewan and most of Alberta.

Figure 2. Predicted oviposition for (Melanoplus sanguinipes) populations across the Canadian prairies (as of August 17, 2020) using climate normal data.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (Philip et al. 2018) as an English-enhanced or French-enhanced version.

Predicted grasshopper development

As of August 10, 2020, the grasshopper model estimates that prairie grasshopper populations are primarily in the adult stage (Fig. 1). Figure 2 provides an overview of where oviposition is predicted to occur based on weather conditions up to August 10. Oviposition is well underway across southern Manitoba and southeastern Saskatchewan (Fig. 2).

Figure 1. Predicted average development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of August 10, 2020).
Figure 2. Predicted oviposition for (Melanoplus sanguinipes) populations across the Canadian prairies (as of August 10, 2020).

Recent warm weather in southwestern Alberta has resulted in increased development rates, resulting in predicted occurrence of oviposition. The three graphs compare grasshopper development at Grande Prairie (Fig. 3), Saskatoon (Fig. 4) and Brandon (Fig. 5). Output suggests that adults are beginning to occur near Grande Prairie but oviposition has yet to begin (Fig. 3). Saskatoon (Fig. 4) and Brandon (Fig. 5) populations should be primarily in the adult stage and oviposition should be well underway.

Figure 3. Predicted grasshopper (Melanoplus sanguinipes) phenology at Grande Prairie AB. Values are based on model simulations (April 1-August 10, 2020).
Figure 4. Predicted grasshopper (Melanoplus sanguinipes) phenology at Saskatoon SK. Values are based on model simulations (April 1-August 10, 2020).
Figure 5. Predicted grasshopper (Melanoplus sanguinipes) phenology at Brandon MB. Values are based on model simulations (April 1-August 10, 2020).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (Philip et al. 2018) as an English-enhanced or French-enhanced version.

Predicted grasshopper development

As of August 3, 2020, the grasshopper model estimates that prairie grasshopper populations are primarily adults (Fig. 1). Based on model simulations, development has been slowest across central and northern regions of Alberta (Fig. 1). The second map provides an overview of where oviposition is predicted to have started (Fig. 2). The yellow and red areas show that oviposition has begun across southern Manitoba and southeastern Saskatchewan (Fig. 2).

Figure 1. Predicted average development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of August 3, 2020).
Figure 2. Predicted oviposition for (Melanoplus sanguinipes) populations across the Canadian prairies (as of August 3, 2020).

The two graphs compare grasshopper development at Saskatoon (Fig. 3) and Brandon (Fig. 4). Near Saskatoon, grasshopper populations are expected to be mainly in the adult stage with oviposition beginning to occur over the past week (Fig. 3). Around Brandon, adult emergence is complete and oviposition should be well underway (Fig. 4).

Figure 3. Predicted grasshopper (Melanoplus sanguinipes) phenology at Saskatoon SK. Values are based on model simulations (April 1-August 3, 2020).
Figure 4. Predicted grasshopper (Melanoplus sanguinipes) phenology at Brandon MB. Values are based on model simulations (April 1-August 3, 2020).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (Philip et al. 2018) as an English-enhanced or French-enhanced version.

Predicted grasshopper development

As of July 19, 2020, the grasshopper model estimates that development of first instar nymphs is complete across most of the prairies and that adult grasshoppers may be beginning to emerge in southern Manitoba and Saskatchewan (Fig. 1; Table 1). Based on model simulations, development has been slowest in the Peace River region where average nymph development ranges between the 2nd and 3rd instar stages (Fig. 1; Table 1). Across the southern prairies, the majority of the nymph population is predicted to be in the 4th and 5th instar stages, with adults predicted to occur across southern Manitoba and Saskatchewan, where grasshopper populations are active (Fig. 1; Table 1).

Figure 1. Predicted average development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of July 19, 2020).

Table 1 indicates that predicted development at Brandon and Winnipeg is well ahead of Lacombe and Grande Prairie. The two graphs below compare grasshopper development at Lacombe (Fig. 2) and Brandon (Fig. 3). Near Lacombe, grasshopper populations are expected to be mainly in the 3rd and 4th instar (Fig. 2). Around Brandon, adult emergence is expected to be well underway, with some lingering 3rd, 4th, and 5th instar individuals remaining in the population (Fig. 3).

Figure 2. Predicted grasshopper (Melanoplus sanguinipes) phenology at Lacombe AB. Values are based on model simulations (April 1-July 19, 2020).
Figure 3. Predicted grasshopper (Melanoplus sanguinipes) phenology at Brandon MB. Values are based on model simulations (April 1-July 19, 2020).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (Philip et al. 2018) as an English-enhanced or French-enhanced version.

Predicted grasshopper development

As of July 12, 2020, the grasshopper model estimates that development across the prairies ranges from 1st instar stage to adults. Based on the model simulations, development has been slowest in the Peace River region where average nymph development ranges between the 2nd and 3rd instars (Fig. 1; Table 1). Across the southern prairies, the majority of the nymph population is predicted to be in the 3rd to 5th instar stages, with adults predicted to occur across southern Manitoba where populations are active (Fig. 1; Table 1). Across the prairies, populations are predicted to be 6, 6, 11, 27, 24, 21 and 5% in egg, first, second, third, fourth, fifth and adult stages, respectively.

Figure 1. Predicted average instar stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of July 12, 2020).

Table 1 indicates that predicted development at Brandon and Winnipeg is well ahead of Lacombe and Grande Prairie. The two graphs compare grasshopper development in Saskatoon (Fig. 2) and Winnipeg (Fig. 3). Grasshopper populations near Saskatoon are predominantly in the 4th and 5th instars with first appearance of adults beginning to occur (Fig. 2). Populations near Winnipeg are expected to be primarily adults (Fig. 3).

Figure 2. Predicted grasshopper (Melanoplus sanguinipes) phenology at Saskatoon SK. Values are based on model simulations (April 1-July 12, 2020).
Figure 3. Predicted grasshopper (Melanoplus sanguinipes) phenology at Winnipeg MB. Values are based on model simulations (April 1-July 12, 2020).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (Philip et al. 2018) as an English-enhanced or French-enhanced version. 

Predicted grasshopper development

As of July 5, 2020, the grasshopper model estimates that hatch is essentially complete. Development is slowest in the Peace River region where the simulation indicates that approximately 30% of the population is still in the egg stage (Fig. 1). Across the prairies, the majority of the nymphal population is predicted to be in the second to fourth instar stages (Table 1; Fig. 1). Development in Manitoba is predicted to be well ahead of most locations across Alberta (Table 1; Fig. 1). Recent warm temperatures in eastern Saskatchewan and Manitoba have resulted in higher rates of grasshopper development. This week, adults are predicted to occur at locations across southern Manitoba and southeastern Saskatchewan (Table 1; Fig. 1). Across the prairies, populations are predicted to be 11, 9, 25, 25, 22, 8 and less than 1% in egg, first, second, third, fourth, fifth and adult stages, respectively (Table 1).

Figure 1. Predicted average instar stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of July 5, 2020).

The two graphs compare predicted development for Saskatoon (Fig. 2) and Winnipeg (Fig. 3). Grasshopper populations near Saskatoon are expected to be predominantly in the third and fourth instars (Fig. 2) while populations near Winnipeg are expected to be primarily in the fifth instar with some adults beginning to appear (Fig. 3).

Figure 2. Predicted grasshopper (Melanoplus sanguinipes) phenology at Saskatoon SK. Values are based on model simulations (April 1-July 5, 2020).
Figure 3. Predicted grasshopper (Melanoplus sanguinipes) phenology at Winnipeg MB. Values are based on model simulations (April 1-July 5, 2020).

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” (Philip et al. 2018) as an English-enhanced or French-enhanced version. 

Predicted grasshopper development

Grasshopper Simulation Model Output – 
Grasshopper development is progressing and populations are primarily in the adult stage (Fig. 1). Based on model runs, approximately 65% of the population should be in the adult stage (50% last week). Grasshopper development continues to be slower than average development. Based on climate data, 80% of the population would be expected to be in adult stage. Model output indicates that oviposition has begun in southern areas prairies (Fig. 2).

Figure 1. Predicted percent of grasshopper (Melanoplus sanguinipes) populations attaining adult stage across the Canadian prairies (as of August 14, 2019). 
Figure 2. Predicted overview of where oviposition has started (as of August 12, 2019).

The Insect of the Week’s Doppelganger featured GRASSHOPPERS for Week 14!!  Check out the excellent nymph photos to help your in-field scouting!

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – Recent, warmer temperatures have resulted in increased grasshopper developmental rates. Surveys in central SK (last week) indicated that grasshopper populations are primarily in the fifth instar and adult stages and in some areas C. pellucida are very abundant. Based on model runs, approximately 50% of the population should be in the adult stage (24% last week). Based on climate data, 60% of the population would be expected to be in adult stage. Model output indicates that oviposition has begun in southern areas prairies. 

The first map (Fig. 1) indicates the average instar for grasshopper populations across the prairies with most areas have grasshopper populations that are in the 5th and adult stages. The second map (Fig. 2) indicates adult populations are developing across areas between 49 and 52 degrees North. The last map (Fig. 3) provides an overview of where oviposition is predicted to have started. The yellow and red areas show that oviposition has began across southern MB, southeastern SK and southern AB.

Figure 1. Predicted development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of August 5, 2019). 
Figure 2. Predicted percent of grasshopper (Melanoplus sanguinipes) populations attaining adult stage across the Canadian prairies (as of August 5, 2019). 
Figure 3.  Predicted overview of where oviposition has started (as of August 5, 2019).

The Insect of the Week’s Doppelganger featured GRASSHOPPERS for Week 14!!  Check out the excellent nymph photos to help your in-field scouting!

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).

Based on model runs, approximately 24% of the population should be in the adult stage. Based on climate data, 32% of the population would be expected to be in adult stage. The first map indicates the average instar for grasshopper populations across the prairies (Fig. 1). The second map indicates adult populations are developing across southern MB and SK and a localized area in southern AB (Fig. 2).

Figure 1. Predicted development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of July 28, 2019). 
Figure 2. Predicted percent of grasshopper (Melanoplus sanguinipes) populations attaining adult stage across the Canadian prairies (as of July 31, 2019). 

The Insect of the Week’s Doppelganger featured GRASSHOPPERS for Week 14!!  Check out the excellent nymph photos to help your in-field scouting!

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).

Cool temperatures continue to result in reduced grasshopper developmental rates. Based on model runs, approximately 68% (50% last week) of the population should be in the 4th-5th instar and adult stages. Based on climate data, 80% of the population would be expected to be in the 4th-5th instar and adult stages. The following map indicates the average instar for grasshopper populations across the prairies (Fig. 1). Development is predicted to be greatest across southern MB and southeastern SK.

Figure 1. Predicted development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of July 21, 2019). 

The Insect of the Week’s Doppelganger featured GRASSHOPPERS for Week 14!!  Check out the excellent nymph photos to help your in-field scouting!

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).

Cool temperatures continue to result in reduced grasshopper developmental rates. Based on model runs, approximately 7% (12.5% last week) of the population is in the first instar, 12% (23% last week) is predicted to be in the second instar, and 27% (32% last week)  is in the third instar, 30% (21% last week) are predicted to be in the fourth instar and 18% (4% last week) are predicted to be in the fifth instar.  As of July 14, 1% of melanopline species are predicted to be in the adult stage. 

The following map (Fig. 1) indicates that grasshopper populations across the southern prairie are mostly in the third and fourth instars. Grasshopper development has been greatest near Winnipeg MB.

Figure 1. Predicted development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of July 15, 2019). 

Last week, the Insect of the Week’s Doppelganger featured GRASSHOPPERS!!!  Check out the excellent nymph photos to help your in-field scouting!

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).

Cool temperatures continue to result in reduced grasshopper development rates. Populations are developing into third and fourth instars. Based on model runs, approximately 13% of the population is in the first instar, 23%  is predicted to be in the second instar, and 32% is in the third instar, 21%  are predicted to be in the fourth instar and l4% may be in the fifth instar. Grasshopper development this season has been similar to long term average development. The following map (Fig. 1) indicates that grasshopper populations across the southern prairie are mostly in the third instar. Compared to last week development has increased across southern regions of the prairies. Grasshopper development has been greatest near Winnipeg MB.

Figure 1. Predicted development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of July 8, 2019). 

This week, the Insect of the Week’s Doppelganger features GRASSHOPPERS!!!  Check out the excellent nymph photos to help your in-field scouting!

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Insect of the Week – Doppelgangers: Grasshoppers

Bruner grasshopper (Melanoplus bruneri) adult. 
Photo credit: S. Barkley, Alberta Agriculture and Forestry.

The case of the prairie grasshoppers: There are 80 grasshopper species on the prairies but only a few that are considered pests. These include Packard (Melanopus packardii), clearwinged (Camnula pellucida), migatory (Melanopus sanguinipes), two-striped (Melanopus bivittatus) and Bruner Melanoplus bruneri) grasshoppers. They are recognizable as grasshoppers (similar body shape and distinctive large rear legs) and, depending on the species, range in size from 21 to 40 centimetres (8.25 to 15.75 inches). Most of these pest species can be distinguished by colouring and size. However, the Bruner and migratory grasshoppers are difficult to tell apart, needing to rely on examining the male genitalia (see Insect of the Week post from July , 2018).

For more information about grasshopper pests, see our Insect of the Week page!

Packard grasshopper – egg, nymph, adult
AAFC
Clearwinged grasshopper – egg, nymph, adult
AAFC
Migratory grasshopper – adult
Joseph Berger, Bugwood.org
Two-striped grasshopper – adult
John Gavloski, Manitoba Agriculture,
Food and Rural Development

More information related to the Bruner grasshopper:

See also:

Predicted grasshopper development (July 5, 2019)

Specific information about these grasshoppers, other pests and natural enemies can be found in the updated Field Crop and Forage Pests and their Natural enemies in Western Canada field guide.

The case of the innocuous versus the evil twin: When making pest management decisions, be sure that the suspect is actually a pest. This can be challenge since insects often mimic each other or look very similar. An insect that looks, moves and acts like a pest may in fact be a look-alike or doppelganger.

Doppelgangers may be related (e.g. same genus) or may not be related, as in the case of monarch butterflies (Danaus plexippus) and viceroys (Limenitis achrippus). Doppelgangers are  usually relatively harmless but sometimes the doppelganger is a pest yet their behaviour, lifecycle or hosts may be different.

Correctly identifying a pest enables selection of the most accurate scouting or monitoring protocol. Identification and monitoring enables the application of economic thresholds. It also enables a producer to select and apply the most effective control option(s) including method and timing of application.  For the rest of the growing season, the Insect of the Week will feature insect crop pests and their doppelgangers.

Review previously featured insects by visiting the Insect of the Week page.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).

Recent cool conditions have resulted in reduced grasshopper development rates. Based on model runs, approximately 22% (33% last week) of the population is in the first instar, 29% (26% last week) is predicted to be in the second instar, and 27% (11% last week) in the third instar, 8.2% (1.5% last week) are predicted to be in the fourth instar and less than 1% may be in the fifth instar (Fig. 1).  Grasshopper development this season has been similar to long term average development. The following map indicates that grasshopper populations across the southern prairie are mostly in the second instar with some areas having populations that are mostly third instars.

Figure 1. Predicted development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of July 1, 2019). 

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).

Across the prairies the grasshopper hatch is well underway with most locations having approximately 27% of the population in the egg stage. Based on model runs, approximately 33% (30% last week) of the population is in the first instar, 26% (14.5% last week) is predicted to be in the second instar, and 11% (4.3% last week) in the third instar and just over 1% are predicted to be in the fourth instar.   The following map indicates that grasshopper populations across the southern prairie are mostly in the second instar.

Figure 1. Predicted development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of June 24, 2019). 

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).

Across the prairies, the grasshopper hatch is well underway this week with most locations having approximately 51% hatch (30% last week). Based on model runs, (i) approximately 30% (21% last week) of the population is in the first instar, (ii) 14.5% (7% last week) is predicted to be in the second instar, and (iii) 4.3% (1% last week) in the third instar.   

Figure 1.  Predicted development stages of grasshopper (Melanoplus sanguinipes) populations across the Canadian prairies (as of June 17, 2019). 

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is available as a free downloadable document in either an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper). 

This week, the grasshopper hatch is well underway across the prairies with most locations having 30% (12% last week) hatch and some areas are predicted to have hatch rates of 75%. Approximately 21% of the population is in the first instar (Fig. 1), 7% (2,5% last week) is predicted to be in the second instar (Fig. 2), and 1% in the third instar.  Grasshopper developmental rates are greatest across southern and central regions of SK. Over the past 30 days this region has experienced the warmest and driest conditions for the prairies. Recent, warm temperatures in southern MB has advanced grasshopper development. 

A survey of roadsides south of Saskatoon this week indicated that melanopline species were primarily first and second second instars.  

Figure 1.  Predicted percent of grasshopper (Melanoplus sanguinipes) population at first instar stage across the Canadian prairies (as of June 11, 2019). 
Figure 2. Predicted percent of grasshopper (Melanoplus sanguinipes) population at second instar stage across the Canadian prairies (as of June 11, 2019). 

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

This week,  the grasshopper hatch is well underway across the prairies (Fig. 1 and 2) with most locations having approximately 15% hatch and some areas having 35% hatch. 

Figure 1. Predicted percent of grasshopper (Melanoplus sanguinipes) population at first instar stage across the Canadian prairies (as of June 4, 2019). 
Figure 2. Predicted percent of grasshopper (Melanoplus sanguinipes) population at second instar stage across the Canadian prairies (as of June 4, 2019). 

Model runs for Saskatoon SK (Fig. 3), Lethbridge AB (Fig. 4), and Grande Prairie AB (Fig. 5) were projected to June 30, 2019. Results for Lethbridge and Saskatoon indicated that populations are primarily in the first and second instars. A survey of roadsides south of Saskatoon indicated that melanoplines were primarily first an second instars. 

Figure 3. Predicted status of Melanoplus sanguinipes populations near Lethbridge  AB projected to June 30, 2019.  
Figure 4.  Predicted status of Melanoplus sanguinipes populations near Saskatoon SK projected to June 30, 2019.  
Figure 5.  Predicted status of Melanoplus sanguinipes populations near Grande Prairie AB projected to June 30, 2019.  

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of May 28, 2019, predicted grasshopper egg development was 72% (66% last week) and is similar to long term average values (75%) (Fig. 1).  Across the prairies, the grasshopper hatch is just beginning with most locations having less than 5% hatch. 

Figure 1. Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 28, 2019. 
Figure 2. Predicted percent of grasshopper (Melanoplus sanguinipes) population at first instar stage across the Canadian prairies (as of May 28, 2019). 

Model runs for Grande Prairie (Fig. 3), Lethbridge (Fig. 4) and Saskatoon (Fig. 5) were projected to June 15, 2019. Results for Lethbridge and Saskatoon indicated that second instars will begin to appear next week. Hatch in near Grande Prairie is  predicted to be approximately one week later.  Development is predicted to be more advanced in northern areas of the Peace River region. 

Figure 3. Predicted status of Melanoplus sanguinipes populations near Grande Prairie AB as of  May 28, 2019.  
Figure 4. Predicted status of Melanoplus sanguinipes populations near Lethbridge AB as of  May 28, 2019.  
Figure 5. Predicted status of Melanoplus sanguinipes populations near Saskatoon SK as of  May 28, 2019.  

This week we surveyed roadsides south of Saskatoon. Though counts were low, melanoplines were primarily first with a few second instars. Slant faced grasshoppers were most abundant, particularly Aeropedellus clavatus.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of May 21, 2019, predicted grasshopper egg development was 66% (63% last week) and is similar to long term average values (68%) (Fig. 1).  

Figure 1. Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 21, 2019. 
Figure 2.  Predicted percent of grasshopper (Melanoplus sanguinipes) population at first instar stage across the Canadian prairies (as of May 21, 2019). 

Model runs for Grande Prairie (Fig. 3), Lethbridge (Fig. 4) and Saskatoon (Fig. 5) were projected to June 15, 2019.  Results for Lethbridge (Fig. 4) and Saskatoon (Fig. 5) indicated that eggs should begin to hatch this week. Hatch in the Peace River region is predicted to be approximately one week later. Results also indicated that initial hatch (less than 6%) should have occurred in southwest SK and southeast AB.

Figure 3.  Predicted status of Melanoplus sanguinipes populations near Grande Prairie AB as of  May 21, 2019.  
Figure 4.  Predicted status of Melanoplus sanguinipes populations near Lethbridge AB as of  May 21, 2019.  
Figure 5.  Predicted status of Melanoplus sanguinipes populations near Saskatoon SK as of  May 21, 2019.  

Reminder – The Prairie Pest Monitoring Network’s 2019 Grasshopper Forecast Map was released in March.  Review all the current risk and forecast maps by linking here.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, areas highlighted orange or red in the 2019 forecast map should be vigilant this spring by performing in-field scouting to assess nymph densities.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Compared to last week, near normal temperatures have resulted in expected development of grasshopper eggs.  This week, as of May 15, 2019, predicted development was 63% and is similar to long term average values (Fig. 1).  

Figure 1.  Predicted grasshopper (Melanoplus sanguinipes) embryological development acrossthe Canadian prairies as of May 15, 2019. 

Model runs for Lethbridge (Fig. 2) and Saskatoon (Fig. 3) were projected to June 15, 2019. Results indicated that eggs should begin to hatch next week. Model predictions, based on long term normal weather data predict that initial hatch near Saskatoon should occur on May 25th.

Figure 2. Predicted status of Melanoplus sanguipes populations near Lethbridge AB as of  May 15, 2019.  
Figure 3.  Predicted status of Melanoplus sanguipes populations near Saskatoon SK as of  May 15, 2019.    

Reminder – The Prairie Pest Monitoring Network’s 2019 Grasshopper Forecast Map was released in March.  Review all the current risk and forecast maps by linking here.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, areas highlighted orange or red in the 2019 forecast map should be vigilant this spring by performing in-field scouting to assess nymph densities.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

This week, cool temperatures this week were predicted to result in minimal embryological development. As of May 7, 2019, predicted development was 60% and is similar to long term average values (Fig. 1). As embryological development approaches 100%, scouting for  nymphs of pest species of grasshoppers should begin.

Figure 1.  Predicted grasshopper (Melanoplus sanguinipes) embryological development across the Canadian prairies as of May 7, 2019. 

Reminder – The Prairie Pest Monitoring Network’s 2019 Grasshopper Forecast Map was released in March.  Review all the current risk and forecast maps by linking here.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, areas highlighted orange or red in the 2019 forecast map should be vigilant this spring by performing in-field scouting to assess nymph densities.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

This week we observed an adult grasshopper (female), Arphia conspersa, in Saskatoon. Model runs were conducted for Grande Prairie, Saskatoon, Swift Current and Lethbridge.  

As of April 30, 2019, predicted development was 60% and is similar to long term average values. The following graph illustrates development for 4 prairie locations (Fig. 1). Hatch is expected to occur during the 3rd week of  May (Saskatoon, Swift Current and Lethbridge) and early June in Grande Prairie.

Figure 1.  Percent predicted embryological development of M. sanguinipes at Grande Prairie AB, Saskatoon SK, Swift Current SK, and Lethbridge AB as of April 30, 2019 (Weiss, Olfert, Vankosky [AAFC] 2019).

Reminder – The Prairie Pest Monitoring Network’s 2019 Grasshopper Forecast Map was released in March.  Review all the risk and forecast maps by linking here.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, areas highlighted orange or red in the 2019 forecast map should be vigilant this spring by performing in-field scouting to assess nymph densities.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Model runs were conducted for Lethbridge AB and Saskatoon SK.  As of April 23, 2019, predicted development was 57% for both locations and is similar to long term average values. The following graph illustrates that gradual development has occurred during the past three weeks. Hatch is expected to occur in mid to late May.

More information can be found by accessing the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Grasshopper populations were predicted to be in the adult stage (Fig. 1A). Development during this growing season is well ahead of average (Fig. 1B).  Development is predicted to be more advanced across the southern prairies than in the Peace River region. 

Figure 1.  Grasshopper development (percent of population) based on model output for the current growing season (A) and for long term normal climate data (B).

This week, adults are predicted to be appearing across the Peace River region (Fig. 2C). 

Figure 2. Predicted grasshopper phenology at Saskatoon (A), Lethbridge (B), and Grande Prairie (C); based on model output for the current growing season (April 1 – July 30, 2018).

Oviposition is ahead, and is predicted to occur across most of the southern prairies (Fig. 3).

Figure 3.  Predicted grasshopper phenology at Saskatoon (A), Lethbridge (B), and Grande Prairie (C); based on model simulations for long term climate normals (April 1 – July 30).
Figure 4.  Clearwinged grasshopper stages including egg, first to fifth instar stages and adult (left to right).

Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 

● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage
2-4  per m² – Very light damage
4-8  per m² – Light damage
8-12 per m² – Action threshold in cereals and canola
12-24 per m² – Severe damage 
>24 per m² – Very severe damage

* For lentils at flowering and pod stages, >2 per m² will cause yield loss.
* For flax at boll stages, >2 per m² will cause yield loss.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of July 23, 2018, most grasshopper populations are predicted to be primarily in the fifth instar or adult stages (Fig. 1A). Development is well ahead of average population development (Fig. 1B). Normally the first appearance of adults occurs during the last week of July (central Saskatchewan).  

Figure 1. Grasshopper development (average instar) based on model simulations for the current growing season (A) and for long term normal climate (B) (April 1 – July 23, 2018).

Grasshopper development varied across the prairies, and was predicted to be more advanced across the southern prairies (e.g., Lethbridge; Fig. 2A) than in the Peace River region (fourth and fifth instar stages; Fig. 2). 

Figure 2. Predicted grasshopper phenology at Lethbridge and Grande Prairie.
Values are based on model simulations, for April 1 – July 23, 2018.
Figure 3.  Clearwinged grasshopper stages including egg, first to fifth instar stages and adult (left to right).

Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 

● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage
2-4  per m² – Very light damage
4-8  per m² – Light damage
8-12 per m² – Action threshold in cereals and canola
12-24 per m² – Severe damage 
>24 per m² – Very severe damage

* For lentils at flowering and pod stages, >2 per m² will cause yield loss.
* For flax at boll stages, >2 per m² will cause yield loss.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of July 16, 2018, the model output indicated that the average instar stage was 4.9, with populations being primarily comprised of fifth instar stage (37%) or adults (33%) (Fig. 1). 

Figure 1. Grasshopper development (average instar) based on model simulations, for April 1 – July 16, 2018.

Development is predicted to be more advanced across the southern prairies; primarily fifth instar stages and adults near Lethbridge AB and Saskatoon SK than in the Peace River region where they are predicted to be mainly fourth and fifth instar stages (Fig. 2).

Figure 2. Predicted grasshopper phenology at Saskatoon (A), Lethbridge (B) and Grande Prairie (C).
Values are based on model simulations, for April 1 – July 16, 2018
Figure 3.  Clearwinged grasshopper stages including egg, first to fifth instar stages and adult (left to right).

Grasshopper Scouting Steps: 

  • Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.
  • Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 
  • Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 
  • A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 
  • At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 

● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage

2-4  per m² – Very light damage

4-8  per m² – Light damage

8-12 per m² – Action threshold in cereals and canola

12-24 per m² – Severe damage 

>24 per m² – Very severe damage

* For lentils at flowering and pod stages, >2 per m² will cause yield loss.

* For flax at boll stages, >2 per m² will cause yield loss.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of July 9, 2018, the grasshopper model output indicates that development is approximately 10 days ahead of normal with populations consisting of 4th and 5th instar stages and adults.  The most rapid grasshopper development occurred across southern and central regions (Fig. 1). 

Figure 1.  Grasshopper development (average instar) based on model simulations, for April 1 – July 9, 2018.

Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 

● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage

2-4  per m² – Very light damage

4-8  per m² – Light damage

8-12 per m² – Action threshold in cereals and canola

12-24 per m² – Severe damage 

>24 per m² – Very severe damage

* For lentils at flowering and pod stages, >2 per m² will cause yield loss.

* For flax at boll stages, >2 per m² will cause yield loss.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of July 2, 2018, the predictive model output indicated that the average instar = 3.7, with 1st instar (5%), 2nd (12%), 3rd (24%), 4th (34%), 5th (23%), and 2.4% in the adult stage. The most rapid development occurred across southern MB and southeast SK (Fig. 1). 

Figure 1.  Grasshopper development (average instar stage) based on model simulations for April 1-July 2, 2018.

Model output for Saskatoon illustrates that populations are primarily in the 4th and 5th instars with appearance of a few adults (Fig. 2).   By comparison, model output based on long-term climate data indicates that grasshopper populations should on average only be in the 3rd and 4th instars (Fig. 3).

Figure 2.  Predicted grasshopper phenology at Saskatoon SK.
Values are based on model simulations for April 1-July 2, 2018.
Figure 3.  Predicted grasshopper phenology at Saskatoon SK.
Values are based on model simulations for Long Term Climate Normals.

Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 

● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage

2-4  per m² – Very light damage

4-8  per m² – Light damage

8-12 per m² – Action threshold in cereals and canola

12-24 per m² – Severe damage 

>24 per m² – Very severe damage

* For lentils at flowering and pod stages, >2 per m² will cause yield loss.

* For flax at boll stages, >2 per m² will cause yield loss.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Insect of the Week – Bruner grasshopper (Orthoptera: Acrididae)

The insect of the week is the Bruner grasshopper (Melanoplus bruneri).  Observed since the 1920s in Canada, this species is a relatively recent addition to the list of grasshopper pest species occurring in crop production areas. Previously, it was not considered a crop pest.

It is a medium-sized grasshopper (males 18-22 mm; females 22-27 mm) with dark and often reddish colour tones. It is similar in appearance and size to the migratory grasshopper (Melanoplus sanguinipes) but is distinguished by differences in the male genitalia. The Bruner grasshopper has recently become the predominant grasshopper species in many northern crop production areas of Alberta and parts of Saskatchewan. It occupies a wide geographic range and is found throughout much of Canada and the United States.

The Bruner grasshopper feeds mainly on broadleaf host plants but the species can feed upon several species of grasses. It has been observed in high numbers feeding in pulse crops, canola, and cereals.

Researchers are investigating if this species follows a two-year life cycle (i.e. do eggs require exposure to two winters before hatching?) in the Peace River region and parts of central Alberta.

For more information, see our Insect of the Week page!

Bruner grasshopper (Melanoplus bruneri) adult.
Photo credit: S. Barkley, Alberta Agriculture and Forestry.

Access these websites for more information related to the Bruner Grasshopper:

Access more information related to grasshoppers here.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of June 24, 2018, the warm weather has resulted in rapid grasshopper development for populations near Saskatoon SK. Model output for Saskatoon predicts that hatch is complete and that populations are primarily in the 4th instar stage (Fig. 1). By comparison, last week’s model output indicated that populations should be primarily in the 2nd and 3rd instar stages. 

Figure 1.  Predicted grasshopper phenology at Saskatoon SK.
Values are based on model simulations for April 1 – June 24, 2018.

Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 

● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage

2-4  per m² – Very light damage

4-8  per m² – Light damage

8-12 per m² – Action threshold in cereals and canola

12-24 per m² – Severe damage 

>24 per m² – Very severe damage

* For lentils at flowering and pod stages, >2 per m² will cause yield loss.

* For flax at boll stages, >2 per m² will cause yield loss.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  


As of June 18, 2018, the model output indicated that the average instar was 2.1 this week (1.7 last week), with 23, 27, 25, 8 and  2% in the 1st, 2nd, 3rd, 4th and 5th instar stages, respectively. The most rapid grasshopper development was predicted to occur across southern Manitoba and southeast Saskatchewan (Fig. 8).

Figure 8.  Grasshopper development (average instar) based on model simulations, for April 1 – June 18, 2018.

Model output for Saskatoon illustrates that populations are primarily in the 2nd and 3rd instar stages with 4th and 5th instar stages beginning to appear (Fig. 9). This agrees with this week’s survey conducted between Saskatoon and Rosetown. Melanoplinae adults were collected at a few sites near Saskatoon and eastern Saskatchewan.

Figure 9.  Predicted grasshopper phenology at Saskatoon SK.
Values are based on model simulations for April 1 – June 18, 2018.
Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 
● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage
2-4  per m² – Very light damage
4-8  per m² – Light damage
8-12 per m² – Action threshold in cereals and canola

12-24 per m² – Severe damage 
>24 per m² – Very severe damage


* For lentils at flowering and pod stages, >2 per m² will cause yield loss.
* For flax at boll stages, >2 per m² will cause yield loss.
Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of June 11, 2018, predicted hatch was 74% (long term average was 28%). The average development is almost at second instar (Fig. 1) with 30, 28, 12 and 2% in the  first, second, third and fourth instar stages, respectively.  

Figure 1.  Grasshopper development (average instar) on model simulations, for April 1 – June 11, 2018.



Model output for Saskatoon illustrates that populations are primarily in the first and second instars with third and fourth instar stages beginning to appear (Fig. 2). This agrees with last week’s survey conducted south of Saskatoon SK. 

Figure 2.  Predicted grasshopper phenology at Saskatoon SK.
Values are based on model simulations, for April 1 – June 11, 2018.
Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of June 4, 2018, predicted hatch was 51% (31% last week; long term average was 11%).  Hatch is predicted to be nearly complete in southeast AB and southern MB (Fig. 1). Grasshopper populations are primarily in the first instar (Fig. 2).

Figure 1. Grasshopper hatch (%) based on model simulations, for April 1-June 4, 2018.
Figure 2.  Percent of grasshopper population that is in the first instar, based on model simulations, for April 1-June 4, 2018.
Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

Above normal temperatures have advanced grasshopper development (Figs. 1 and 2). As of May 28, 2018, predicted hatch was 31% (up from 6% last week).

Figure 1. Grasshopper embryological development (%) based on model simulations (April 1-May 28, 2018). 
Figure 2.  Grasshopper hatch (%) based on model simulations (April 1-May 28, 2018).

Reminder – The Prairie Pest Monitoring Network’s 2018 Grasshopper Forecast Map was released in March (Fig. 3).  Spring temperatures, soil moisture conditions, and precipitation all have an impact on survival of overwintered grasshopper eggs. Growers in areas highlighted orange or red in the map below should be vigilant this spring.

Figure 3.  Grasshopper forecast map (M. sanguinipes) for 2018 growing season.
Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  


Recent warm conditions have advanced egg development. As of May 21, 2018, predicted mean egg development was 78% (68% last week) and model output indicates that embryological development was 10% greater than long term average. Greatest development was predicted to be across Alberta, particularly in an area extending from Lethbridge to Edmonton (Fig. 1 and 2). Last week first instar grasshoppers were collected near Rosetown SK. 

Figure 1. Grasshopper embryological development (%) for
April 1 – May 21, 2018, based on model simulations.
Figure 2. Grasshopper hatch (%) for April 1 – May 21, 2018, based on model simulations.

Reminder – The Prairie Pest Monitoring Network’s 2018 Grasshopper Forecast Map was released in March (Fig. 3).  Spring temperatures, soil moisture conditions, and precipitation all have an impact on survival of overwintered grasshopper eggs. Growers in areas highlighted orange or red in the map below should be vigilant this spring.

Figure 3.  Grasshopper forecast map (M. sanguinipes) for 2018 growing season.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  


As of May 13, 2018, predicted mean egg development was 68% (62% last week) and model output indicates that embryological development was 5% greater than long term average. Greatest development was predicted to be across southern Alberta with potential for hatch occurring near Medicine Hat and Bow Island (Fig. 6).

Figure 1. Grasshopper (M. sanguinipes) embryological development (%) based on
model simulations for April 1-May 13, 2018.

Reminder – The Prairie Pest Monitoring Network’s 2018 Grasshopper Forecast Map was released in March (Fig. 2).  Spring temperatures, soil moisture conditions, and precipitation all have an impact on survival of overwintered grasshopper eggs. Growers in areas highlighted orange or red in the map below should be vigilant this spring.

Figure 2.  Grasshopper forecast map (M. sanguinipes) for 2018 growing season.



Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.


Predicted grasshopper development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  

As of May 6, 2018, predicted mean development was 62% (slightly greater than long term average of 56%).  The greatest development was predicted to be across southern AB (Fig. 1).

Figure 1. Grasshopper embryological development (%) based on model simulations, for April 1 – May 6, 2018.



Reminder – The Prairie Pest Monitoring Network’s 2018 Grasshopper Forecast Map was released in March.  Review all the risk and forecast maps by linking here.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, growers in areas highlighted orange or red in the map below should be vigilant this spring.

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba AgricultureSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – Based on model output, grasshopper development is slightly ahead of long term averages with approximately 80% of the population in the adult stage.  The following map presents model data for oviposition. Given the warm conditions across the southern prairies, it is not surprising that oviposition rates are predicted to be greatest in southern Alberta and in south-central Saskatchewan.



Grasshopper scouting steps can be reviewed in the previous Week 13 Post.


Reminder:  Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – Based on model output, grasshopper development is slightly ahead of long term averages. The greatest development was predicted to be across southern regions in all three provinces, particularly southern Alberta. Grasshoppers should be predominantly in the fourth and fifth instar stages with adults present across most of the region. 


  

Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Start at one end in either the field or the roadside and walk toward the other end of the 50 m, making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 
● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage
2-4  per m² – Very light damage
4-8  per m² – Light damage
8-12 per m² – Action threshold in cereals and canola


12-24 per m² – Severe damage 
>24 per m² – Very severe damage


* For lentils at flowering and pod stages, >2 per m² will cause yield loss.
* For flax at boll stages, >2 per m² will cause yield loss.



Reminder:  Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – Based on model output, development is slightly ahead of long term normal (LTN). Grasshoppers should be predominantly in the third and fourth instar stages with more rapid development across southern Alberta. Last week the mean instar was 3.4; this week it increased to 4.1. 

Figure 1. Predicted Melanoplus sanguinipes development across 
the Canadian prairies (July 16, 2017).



Figure 2. Predicted Melanoplus sanguinipes development prepared 
using Long Term Normal (LTN) data.

  

Figure 3.  Predicted percent of Melanoplus sanguinipes at fifth instar 
development stage (July 16, 2017).



This is the first week where the model has predicted appearance of adults. As of July 16, 2017 adults should be occurring across 45% of the prairies (compared to long term average value of 39%). 

Figure 4.  Predicted percent of Melanoplus sanguinipes at adult stage (July 16, 2017).



Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 
● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage
2-4  per m² – Very light damage
4-8  per m² – Light damage
8-12 per m² – Action threshold in cereals and canola



12-24 per m² – Severe damage 
>24 per m² – Very severe damage


* For lentils at flowering and pod stages, >2 per m² will cause yield loss.
* For flax at boll stages, >2 per m² will cause yield loss.





Reminder:  Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – Compared to last week, grasshopper development has progressed by approximately one instar (Fig. 1).  Based on model output, grasshopper development is slightly ahead of long term averages (Fig. 2).  

Figure 1. Predicted Melanoplus sanguinipes development across 
the Canadian prairies (July 4, 2017).



Figure 2. Predicted Melanoplus sanguinipes development prepared 
using Long Term Normal (LTN) data.



Across the prairies, grasshoppers should be predominantly in the third and fourth instar stages with more rapid development across southern Alberta (Fig. 3 and 4). This is the first week where the model has predicted appearance of adults. The greatest development was predicted to be across southern regions in all three provinces, particularly southern Alberta.  Current developmental rates are well behind last year.

Figure 3.  Predicted percent of Melanoplus sanguinipes at fourth instar 
development stage (July 10, 2017).



Figure 4.  Predicted percent of Melanoplus sanguinipes at fifth instar 
development stage (July 10, 2017).





Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 
● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage
2-4  per m² – Very light damage
4-8  per m² – Light damage
8-12 per m² – Action threshold in cereals and canola



12-24 per m² – Severe damage 
>24 per m² – Very severe damage


* For lentils at flowering and pod stages, >2 per m² will cause yield loss.
* For flax at boll stages, >2 per m² will cause yield loss.





Reminder:  Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – Based on model output, grasshopper development is very similar to long-term averages.  Across the prairies, grasshoppers should be predominantly in the second and third instar stages with more rapid development across southern Alberta. The greatest development was predicted to be across all of the southern regions.

Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 
● Compare counts to the following damage levels associated with pest species of grasshoppers:

0-2  per m² – None to very light damage
2-4  per m² – Very light damage
4-8  per m² – Light damage
8-12 per m² – Action threshold in cereals and canola

12-24 per m² – Severe damage 
>24 per m² – Very severe damage


* For lentils at flowering and pod stages, >2 per m² will cause yield loss.
* For flax at boll stages, >2 per m² will cause yield loss.

Reminder:  Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – Predicted hatch was 71% (52% last week) with 30% of the population in the first instar, 26% second instar, 12% third instar and 2% in the fourth instar. Across the prairies, the mean developmental stage was second instar. The greatest development was predicted to be across southern regions in all three provinces. 





Grasshopper populations near Saskatoon were predicted to be primarily in the second instar this week with the appearance of third and fourth instars. Model output suggests that grasshopper development is slightly ahead of average development. Based on long term meteorological data, populations should be predominantly in the first and second instars with a low number being third instars. This week’s survey (SW of Saskatoon) indicates that most melanopline grasshoppers are already in the second and third numbers.  





Grasshopper Scouting Steps: 

● Measure off a distance of 50 m on the level road surface and mark both starting and finishing points using markers or specific posts on the field margin.

● Starting at one end in either the field or the roadside and walk toward the other end of the 50 m making some disturbance with your feet to encourage any grasshoppers to jump. 

● Grasshoppers that jump/fly through the field of view within a one meter width in front of the observer are counted. 

● A meter stick can be carried as a visual tool to give perspective for a one meter width.  However, after a few stops one can often visualize the necessary width and a meter stick may not be required. Also, a hand-held counter can be useful in counting while the observer counts off the required distance. 

● At the end point the total number of grasshoppers is divided by 50 to give an average per meter. For 100 m, repeat this procedure. 
● Compare counts to the following damage levels associated with pest species of grasshopers:

0-2  per m² – None to very light damage
2-4  per m² – Very light damage
4-8  per m² – Light damage
8-12 per m² – Action threshold in cereals and canola


12-24 per m² – Severe damage 
>24 per m² – Very severe damage



* For lentils at flowering and pod stages, >2 per m² will cause yield loss.
* For flax at boll stages, >2 per m² will cause yield loss.

Reminder:  Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – Simulation modelling is used to predict grasshopper development across the prairies. Weekly temperature data is incorporated into the model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper). Predicted hatch for June 11, 2017, was 52% (23% last week) with 32% of the population in the first instar, 15% second instar and 15% third instar. 

The greatest development was predicted to be across southern regions in all three provinces, particularly southeastern Alberta and a region extending south from Swift Current/Regina to the US border. 



Grasshopper populations near Saskatoon were predicted to be primarily in the second instar with appearance of some third and fourth instars. This week’s survey (southwest of Saskatoon) agreed with model predictions with first collections of a few fourth instars.  





Model output for Grande Prairie indicates that development continues to be approximately 10 days later than locations across the southern prairies.

Reminder:  Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  



As of June 5, 2017, model output suggests that most of the population is still at the egg stage. However, recent warm conditions have advanced grasshopper development. Predicted hatch was 23% (17% first instar and 6% second instar) across the prairies (up from 7% last week). Development was predicted to be most advanced across southern regions in all three provinces, particularly southeastern Alberta and a region extending south from Regina to the USA border. 



Though it is still early in the growing season, grasshopper hatch can vary across the prairies. Model output indicates that development near Vauxhall is one week ahead of Saskatoon and three weeks faster than Grande Prairie. This suggests that peak hatch at Grande Prairie may not occur until late June.






The following image showing various stages of the clearwinged grasshopper is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  


Reminder:
– The Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map can be viewed here.  

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  



As of May 29, 2017, predicted mean embryological development was 77% (70% last week); the greatest development was predicted to be across southern regions in all three provinces, particularly southern Alberta (Fig. 1). Hatch was predicted for a few, isolated locations with approximately 7% hatch (Fig. 1).

Figure 1. Predicted embryological development of Migratory grasshopper  (Melanoplus
sanguinipes
) eggs across the Canadian prairies as of May 29, 2017.



For comparison, the map below (Fig. 2) indicates that the predicted M. sanguinipes hatch is actually slower than normal. This week, 93% of the population should be in the egg stage and 6.5% in the first instar. Predicted warm conditions for May 31 and June 1 should result in completion of the egg stage.  Though it is still early in the growing season, grasshopper hatch can vary across the prairies. 

Figure 2.   Predicted embryological development of Migratory grasshopper  (Melanoplus sanguinipes) eggs
across the Canadian prairies as of May 29, 2017, using Long Term Normal data
.





Reminders:
– Review the predicted M. sanguinipes phenologies generated for Week 4 for Regina SK, Lethbridge AB and Grande Prairie AB.
– The Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map can be viewed here.  

Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  


As of May 22, 2017, predicted mean embryological development was 70% (66% last week); the greatest development was predicted to be across southern regions in all three provinces (similar to long term averages; Fig. 1).  


Figure 1.  Simulation model outputs mapped to predict the embryological development of Migratory grasshopper  (Melanoplus sanguinipes) eggs across the Canadian prairies as of May 15, 2017).
 
Model output indicates that development near Regina SK (Fig 2, Top) is slightly greater than Lethbridge AB (Fig. 2, Middle). Hatch in Lethbridge is predicted to be two weeks ahead of model predictions for Grande Prairie AB (Fig 2, Bottom). 
 



Figure 2. Predicted development of Migratory grasshoppers near Regina SK (Top), Lethbridge AB (Middle), and Grande Prairie AB (Bottom). 
 

 

Reminder – The Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map can be viewed here.  


Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  


As of May 15, 2017, the predicted mean embryological development was only slightly ahead of last week at 66% (compared to 62% last week), and similar to long term averages (64%; Fig. 1). Although it is still early in the growing season, grasshopper hatch can vary across the prairies. For example, model output indicated that the hatch in Vauxhall AB was predicted to be about a week ahead of Saskatoon SK. As a result, timing of peak hatch could be 10-14 days earlier in Vauxhall than Saskatoon.


Figure 1.  Simulation model outputs mapped to predict the embryological development of Migratory grasshopper  (Melanoplus sanguinipes) eggs across the Canadian prairies as of May 15, 2017).


Reminder – The Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map (Fig. 2) was released in January.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, growers in areas highlighted orange or red in the map below should be vigilant as nymphs begin to hatch this season.

Figure 2. Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map.


Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  


As of May 8, 2017, predicted mean embryological development was 62% (56% last week); the greatest development was predicted to be across southern Saskatchewan. Embryological development was very similar to long term averages (60%) though well behind 2016 (74%). Hatch was not predicted for any locations. 

Reminder – The Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map (Figure 1) was released in January.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, growers in areas highlighted orange or red in the map below should be vigilant as nymphs begin to hatch this season.

Figure 1. Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map.


Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  


As of May 1, 2017, model output predicted embryological mean development was 56%; the greatest development was predicted to be across the southern prairies. Embryological development was very similar to long term averages (57%) though marginally slower than 2016 (62%).


Reminder – The Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map (Figure 1) was released in January.  While spring temperatures, soil moisture conditions, and precipitation can all have an impact on overwintered grasshopper eggs, growers in areas highlighted orange or red in the map below should be vigilant as nymphs begin to hatch this season.

Figure 1. Prairie Pest Monitoring Network’s 2017 Grasshopper Forecast Map.



Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

2017 Risk and Forecast Maps for the Prairies

The 2017 Prairie-Wide Risk and Forecast Maps can be viewed and downloaded here. Maps are generated for bertha armyworm, grasshoppers, wheat midge, cabbage seedpod weevil, pea leaf weevil, wheat stem sawfly, diamondback moth as well as average temperature, average precipitation, and modeled soil moisture for the Canadian prairies.


Thank you to the many people who monitor each growing season!  An astonishing 6414 survey stops were involved in the insect monitoring performed across the Canadian prairies in 2016!


Manitoba insect survey and forecast maps

Manitoba posts their 2016 Insect Survey and 2017 Forecast Maps up on their website! Take a moment to look over the following forecasts:

Manitoba growers can access general information on pest and beneficial insects from a series of fact sheets posted at the Insect section of their website.

More information related to the above maps and insects can be obtained by contacting Manitoba Agriculture entomologist John Gavloski.

Saskatchewan Insect Survey and Forecast Maps are available on Saskatchewan.ca

All the Saskatchewan Insect Survey and Forecast Maps and more can be found on Saskatchewan.ca ! To view all our agriculture maps check out our Maps for Farmers and Agribusiness section.

The Saskatchewan 2016 Bertha Armyworm moth accumulation map is posted.
The Saskatchewan 2016 Cabbage Seedpod Weevil Survey Map is posted.
Saskatchewan’s 2016 Pea Leaf weevil Survey Map can be viewed.
The Saskatchewan 2017 Grasshopper Forecast Map is posted now.
Also, the Saskatchewan 2017 Wheat Midge Forecast Map is posted now.

Saskatchewan growers can access general Insect pest information located under our Crop Protection section.

More information related to the above maps and insects can be obtained by contacting Saskatchewan Agriculture’s Scott Hartley or Danielle Stephens.

Alberta 2017 Forecast and 2016 Risk Maps plus updates to Alberta Agriculture and Forestry web pages

Alberta has posted their forecast and survey maps for several insect pest species occurring in field crops.  Visit their home page to view all the Alberta maps.

The following list and hyperlinks were provided by Shelley Barkley via the Alberta Insect Pest Monitoring Network.

Scott Meers, entomologist with Alberta Agriculture and Forestry, was interviewed and spoke about Alberta insect forecasts for 2017.  That series of five interviews can be access with the following hyperlinks:

  1. 2017 Wheat Stem Sawfly and Cabbage Seedpod Weevil Forecasts
  2. 2017 Pea Leaf Weevil Forecast
  3. 2017 Wheat Midge Forecast
  4. 2017 Bertha Armyworm Forecast
  5. Grasshoppers

Additionally, Alberta Agriculture and Forestry has updated their webpages with the following:

  1. They have created a graphic that illustrates the “range expansion” of 2 evil weevils in Alberta: pea leaf and cabbage seedpod.
  2. Similar graphics have been added to their bertha armyworm page.  Check out the past “six years of bertha armyworm moth” in Alberta which can be accessed via an hyperlink positioned on their bertha armyworm web page
  3. Their grasshopper page has been updated too – check out the “historic grasshopper maps” for Alberta via a hyperlink located on their grasshopper web page
  4. The past “eight years of sawfly” in Alberta can be accessed via a hyperlink located on their wheat stem sawfly web page.
  5. Remember, if you have access to a large format printer, a poster of the 6 Alberta insect forecast maps is available to print.

Weekly Update – Grasshoppers (Updated)

Grasshoppers (Acrididae) – Across the prairies the model indicates that 80% of the population should be in the adult stage. This is approximately 10% greater than average. Oviposition is predicted to be well underway and is most advanced in Manitoba and southeast Saskatchewan.  




In central Saskatchewan, grasshopper development is slightly ahead of average development. The following graph shows predicted grasshopper development at Saskatoon for August 7, 2016. The model indicates that oviposition is well underway.  


Melanopline development for Saskatoon (August 12, 2016) was 5.6. The most abundant species was M. dawsoni (40%), followed by M. bivittatus (21.6%).





Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Grasshoppers

Grasshoppers (Acrididae) – This post has been updated!  Please view it here!

Weekly Update – Grasshoppers

Grasshoppers (Acrididae) – Across the prairies the model indicates that 80% of the population should be in the adult stage. This is approximately 10% greater than average. Oviposition is predicted to be well underway with oviposition being the most advanced in MB and SE SK.

Msang Oviposition.jpg
The following graph shows predicted grasshopper development at Saskatoon for August 7, 2016


Weekly Update – Grasshoppers

Grasshoppers (Acrididae) – In central Saskatchewan, grasshopper development is currently more than 1-2 weeks ahead of average development. 

The following graph shows predicted grasshopper development at Saskatoon for July 17, 2016. The model indicates that fourth and fifth instar numbers have peaked and that adult grasshopper numbers are increasing. 





The second graph illustrates grasshopper development (for Saskatoon) based on Long Term Normal (LTN) data. Based on average weather, the population should be primarily in the fourth instar with increasing numbers of fifth instars and adults. 

Sentinel site results in Saskatchewan (July 13, 2016) indicated that the mean melanopline instar was 3.4. Melanoplus dawsoni was the dominant species (40.4%), followed by M. bivittatus (21.6%). Melanopline adults have been collected for M. dawsoni, M. bivittatus and M. sanguinipes.


Reminders:

– The following image showing various stages of Camnulla pellucida is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  

Figure 1. Life stages of Camnulla pellucida which including eggs, first-fifth instar nymphs and adult (L-R).


– Generally, the economic threshold for grasshoppers in cereals is 8-12 per square metre but will vary by crop and growing conditions.


Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Grasshoppers

Grasshoppers (Acrididae) – Across the prairies, the predicted mean instar of Melanoplus sanguinpes is 4.5 with adults appearing in many areas across the prairies.  In central Saskatchewan, grasshopper development continues to be more than 2-3 weeks ahead of average development. 



The following graph shows grasshopper development at Saskatoon for 2016. The model indicates that fifth instar numbers are beginning to peak and that adult grasshopper densities are increasing. 




The second graph below illustrates grasshopper development (for Saskatoon) based on LTN data. Based on average weather, the population should be primarily in the third instar and fourth instars with increasing numbers of fifth instars.  Adults are not predicted to occur until July 19. 



Reminders:

The following image showing various stages of Camnulla pellucida is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  

Figure 1. Life stages of Camnulla pellucida which including eggs, first-fifth instar nymphs and adult (L-R).



– Generally, the economic threshold for grasshoppers in cereals is 8-12 per square metre but will vary by crop and growing conditions.


Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Grasshoppers

Grasshoppers (Acrididae) – Previous model predictions related to hatch and nymphal instar development can be reviewed here.  


The following image showing various stages of Camnulla pellucida is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  


Generally, the economic threshold for grasshoppers in cereals is 8-12 per square metre but will vary by crop and growing conditions.

Figure 1. Life stages of Camnulla pellucida which including eggs, first-fifth instar nymphs and adult (L-R).
Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Grasshoppers

Grasshoppers (Acrididae) – Previous model predictions related to hatch and nymphal instar development can be reviewed here.  

For the week of June 19, 2016, warm conditions in southeastern Saskatchewan and southern Manitoba were predicted to result in enhanced grasshopper development. Across the prairies, grasshoppers should be between the first and fifth instars. The model predicted that approximately 15% of the population was predicted to be in the first instar, 35% second, 28% third, 13% fourth instar and just under one percent fifth instar.  Development is well ahead of average rates (22% first instar, 14% second instar and 10% third instar). 



In central Saskatchewan, grasshopper development is currently more than two weeks ahead of average development. The following graph shows grasshopper development at Saskatoon based on 2016 data. The model indicates that fifth instar grasshoppers should be present.





Now compare the above with the following graph which illustrates grasshopper development (for Saskatoon) based on long term normal (LTN) data.  The model indicates that  primarily first instars are predicted to be present with only the initial appearance of third instar nymphs. 



The following image showing various stages of the clearwinged grasshopper is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  


Figure 1. Life stages of Camnulla pellucida  which including eggs, first-fifth instar nymphs and adult (L-R).


Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Grasshoppers

Grasshoppers (Acrididae) – Previous model predictions related to hatch and nymphal instar development can be reviewed here.  

Reminder – Weekly surveying conducted by AAFC-Saskatoon Staff on June 2, 2016, confirmed that Melanoplines were primarily first and second instar stages although a few third instar nymphs were collected.

The following image showing various stages of the clearwinged grasshopper is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  

Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Predicted Grasshopper Development

Grasshoppers (Acrididae) – Warm temperatures in Saskatchewan and southern Manitoba were predicted to result in enhanced development. 


The model predicted that 41% of the hatch is complete (versus 23% last week)


Approximately 25% of the population was predicted to be in the first instar whereas 11% were predicted to be in the second instar.  Development is well ahead of average rates (9% hatch, 7% first instar and 2% second instar). 






Weekly surveying conducted by AAFC-Saskatoon Staff on June 2, 2016, confirmed that Melanoplines were primarily first and second instar stages although a few third instar nymphs were collected.

The following image showing various stages of the clearwinged grasshopper is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  




Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Predicted Grasshopper Development

Grasshoppers (Acrididae) – This past week, warm conditions conditions in Saskatchewan were predicted to result in enhanced development. 


For the week of May 29, 2016, the predicted mean embryological development was 87% and indicates that grasshopper hatch will continue to progress over the next week to ten days. The model predicted that 23% of the hatch is complete (compared to 13% predicted last week). Approximately 15% of the population was predicted to be in the first instar and 7% in the second instar.



The following image showing various stages of the clearwinged grasshopper is provided below – note that adults have wings extending the length of the abdomen whereas nymphs lack wings but develop wing buds that will eventually mature to wings.  




Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Predicted Grasshopper Development

Grasshoppers (Acrididae) – This past week, cooler conditions in Alberta slowed egg development while warmer conditions in Saskatchewan enhanced development. 


For the week of May 23, 2016, the predicted mean embryological development was 85% compared to 75% for the previous week. These results suggest that grasshopper hatch will rapidly progress over the next week to ten days



The model predicted that 13% of the hatch is complete (compared to last week’s value of 5%). Peak hatch (approx. 30%) was predicted to occur between Saskatoon and Regina.

Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.

Weekly Update – Predicted Grasshopper Development

Grasshoppers (Acrididae) – Cooler conditions over the past seven days resulted in a return to average grasshopper development. 


For the week of May 8-15, 2016, the predicted mean embryological development was 75% (last week was 74%).  Grasshopper egg development is greater than 80% across most of southern and central Alberta indicating that hatch will rapidly progress over the next two weeks within the areas highlighted in red on the map below. The model predicted that 5% of the hatch is already underway. Peak hatch (approx. 16%) was predicted to occur in the area around Alsask SK to Hanna AB and south to Brooks and Vauxhall AB.


Recall that the 2016 Grasshopper Forecast Map circulated in January predicted the following risk areas.  




Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of ManitobaSaskatchewanAlbertaBritish Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.




Weekly Update – Predicted Grasshopper Development

Grasshoppers (Acrididae) – Warm conditions over the past seven days have resulted in rapid grasshopper development. Predicted mean embryological development was 74% (last week was 62%) with greatest development predicted to be in southern AB. Embryological development is predicted to be 16% ahead of long term average values (prairie wide). The model predicts that 4% of the hatch is complete (AB, SK and MB).



Recall that the 2016 Grasshopper Forecast Map circulated in January predicted the following risk areas.  







Biological and monitoring information related to grasshoppers in field crops is posted by the provinces of Manitoba, Saskatchewan, Alberta, British Columbia and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English-enhanced or French-enhanced versions are available.


Weekly Update – Predicted Grasshopper Development

Grasshopper Simulation Model Output – The grasshopper simulation model will be used to monitor grasshopper development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of grasshopper development stages based on biological parameters for Melanoplus sanguinipes (Migratory grasshopper).  


Warm, dry conditions typically enhance grasshopper egg development.  The predicted mean embryological development of the migratory grasshopper (Orthoptera: Melanoplus sanguinipes) was 62% this week.  The greatest development was predicted to be in Alberta (note areas shaded orange).






Biological and monitoring information related to grasshoppers in field crops is posted by Manitoba Agriculture, Food and Rural Development, Saskatchewan Agriculture, Alberta Agriculture and Forestry, the BC Ministry of Agriculture and the Prairie Pest Monitoring Network.  Also refer to the grasshopper pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” as an English-enhanced or French-enhanced version.

2016 Risk and Forecast Maps for the Prairies

The most recent insect pest maps of the 2016 forecast maps can be viewed and downloaded here.

Weekly Update

Prairie Pest Monitoring Network Weekly Updates – July 15, 2015
Otani, Giffen, Svendsen, Olfert


  1. Greetings!  This week grasshoppers, cabbage seedpod weevil and wheat midge were important pests based on provincial reports and reminders for in-field scouting.  Rain fell in some areas of the prairies but many continue to wait for moisture.  Remember, a downloadable version of this Weekly Update can be accessed here.  


  1. Weather synopsis – Thanks to the folks who compile and manage the agroclimate maps posted by AAFC!  The map below shows the Accumulated Precipitation the past 7 days (i.e., July 7-13, 2015):


While the map below reflects the Accumulated Precipitation for the Growing Season (i.e., April 1-July 13, 2015):


The map below reflects the Percent of Normal Precipitation for the Growing Season (i.e., April 1-July 13, 2015) for comparison:

The map below shows the Lowest Temperatures the Past 7 Days (July 7-13, 2015) across the prairies:


While the map below shows the Highest Temperatures the Past 7 Days (July 7-13, 2015) across the prairies:
The updated growing degree day (GDD) (Base 5ºC, March 1 – July 12, 2015) map is below:


While the growing degree day (GDD) (Base 10ºC, March 1 – July 12, 2015) map is included below:




  1. Bertha armyworm (Mamestra configurata) – Low cumulative counts of BAW moths were again reported in pheromone traps throughout the prairies this week.


In-field monitoring for egg masses (Refer to photo below) and newly emerged larvae (photo below) should initially focus on the undersides of leaves plus watch the margins of leaves for feeding.  Bertha armyworm larvae will also feed on newly developing pods so the whole plant should be examined.  Watch for the following life stages:



Reminder:  Some bertha armyworm larvae remain green or pale brown throughout their larval life. Large larvae may drop off the plants and curl up when disturbed, a defensive behavior typical of cutworms and armyworms. Young larvae chew irregular holes in leaves, but normally cause little damage. The fifth and sixth instars cause the most damage by defoliation and seed pod consumption. Crop losses due to pod feeding will be most severe if there are few leaves. Larvae eat the outer green layer of the stems and pods exposing the white tissue. At maturity, in late summer or early fall, larvae burrow into the ground and form pupae.


Monitoring:
Larval sampling should commence once the adult moths are noted. Sample at least three locations, a minimum of 50 m apart. At each location, mark an area of 1 m2 and beat the plants growing within that area to dislodge the larvae. Count them and compare the average against the values in the economic threshold table below:  


Table 1.  Economic thresholds for Bertha armyworm in canola (courtesy Manitoba Agriculture, Food and Rural Initiatives).
Expected Seed Value – $ / bushel*
Spraying cost –
$ / acre
6
7
8
9
10
11
12
13
14
15
16
Number of Larvae / metre2 *
7
20
17
15
13
12
11
10
9
9
8
8
8
23
20
17
15
14
13
11
11
10
9
9
9
26
22
19
17
16
14
13
12
11
10
10
10
29
25
22
19
17
16
14
13
12
11
11
11
32
27
24
21
19
17
16
15
14
13
12
12
34
30
26
23
21
19
17
16
15
14
13
13
37
32
28
25
22
20
19
17
16
15
14
14
40
35
31
27
24
22
20
19
17
16
15
15
43
37
32
29
26
23
22
20
19
17
16
* Economic thresholds for bertha armyworm are based on an assumed yield loss of 0.058 bu/acre for each larva/metre2 (Bracken and Bucher. 1977. Journal of Economic Entomology. 70: 701-705).


  1. Grasshoppers (Camnulla pellucida, Melanoplus sanguinipes, M. bivittattus, M. packardii) – In-field scouting along field margins and in ditches AND within the field is critical now with the exceedingly dry growing conditions!  


Scouting – Remember only five or six grasshopper species of the 80+ that occur on the prairies are regarded as crop pests.  The lifecycles of these six economically important species are similar.  Nymphs hatch from overwintered eggs in the spring.  Nymphs develop through five stages or instars before becoming adults.  Typically, the most serious economic damage will occur from the third to fifth instar stages but all stages need to be monitored.  The life stages of the clearwinged grasshopper (Camnulla pellucida) are shown below.  Note that adults possess fully formed wings that extend the entire length of the abdomen.


Life stages of the clearwinged grasshopper include (left to right) eggs which overwinter, first instar nymphs that hatch in the spring followed by second, third, fourth and fifth instar nymphs which finally develop into the adult stage.


Need help distinguishing grasshopper nymph stages?  Saskatchewan Agriculture’s latest Insect Update includes line drawings to help!  It also includes a summary of economic thresholds for grasshoppers in various crops.


Economic thresholds for grasshoppers are posted by Manitoba Agriculture, Saskatchewan Agriculture, Alberta Agriculture and Forestry, BC Ministry of Agriculture, and the Prairie Pest Monitoring Network.


  1. Diamondback Moth (Plutella xylostella) – In-field monitoring for DBM larvae should continue this week.


Larval Monitoring:
Once the diamondback moth is present in the area, it is important to monitor individual canola fields for larvae.  Remove the plants in an area measuring 0.1 m2 (about 12″ square), beat them on to a clean surface and count the number of larvae dislodged from the plant. Repeat this procedure at least in five locations in the field to get an accurate count.  
Remember, parasitoid wasps attacking DBM larvae (Refer to photo below) are already present in fields.  Use the economic thresholds to preserve these beneficial wasps by NOT applying insecticide until DBM larval densities exceed the threshold.


Diamondback larva (upper left) and pupal silk cocoon (upper right), Diadegma insulare adult and early instar Diamondback moth larvae on canola leaf (lower left) and D. insulare pupae (N=2) within Diamondback moth pupal silk cocoons (lower right).



Economic threshold for diamondback moth in canola at the advanced pod stage is 20 to 30 larvae/ 0.1 m2 (approximately 2-3 larvae per plant).  Economic thresholds for canola or mustard in the early flowering stage are not available. However, insecticide applications are likely required at larval densities of 10 to 15 larvae/ 0.1 m2 (approximately 1-2 larvae per plant).


Please also refer to fact sheets for DBM posted by Manitoba Agriculture, Food and Rural Development, Saskatchewan Agriculture, Alberta Agriculture and Forestry, and the Prairie Pest Monitoring Network.  


  1. Wheat Midge (Sitodiplosis mosellana) – This season, predictive modelling was used in an attempt to forecast wheat midge emergence.  In 2014, the degree-day model proposed by German researchers (Basedow) was used to predict adult midge emergence in the Peace River region compared to the 5°C base temperature model which corresponds well to midge emergence throughout central and southern areas of the prairies.  The map below predicts the geographic distribution and corresponding accumulation of heat units necessary for wheat midge to emerge from puparia developing in the soil.  


The map below indicates the predicted status of wheat midge emergence with 10% of resident midge population emerged in areas highlighted yellow (600-693 DD), 50% in areas highlighted gold (693-784 DD), and 90% of resident midge emerged in areas highlighted orange (784-874 DD) using current weather data (up to July 12, 2015).  Wheat midge emergence is predicted to be 100% completed (as of July 12, 2015) with the initial midge larvae now expected to be found within wheat heads growing in southern Alberta, southeast Saskatchewan, southwest Manitoba and to the south of Winnipeg.  Wheat midge emergence is predicted to be 90% completed (as of July 12, 2015) throughout most of the boreal region of the prairies and in the north Peace.  Wheat midge emergence is predicted to be 50% completed (as of July 12, 2015) throughout the remaining portions of the prairies.  



When monitoring wheat fields, pay attention to the synchrony between flying midge and anthesis.  Additional wheat midge biology and monitoring information can be located by clicking here or linking to your provincial fact sheet (Saskatchewan Agriculture or Alberta Agriculture and Forestry).  More information related to wheat midge on the Canadian prairies was published by Elliott, Olfert, and Hartley in 2011.  


REMEMBER that in-field counts of wheat midge per head remain the basis of economic threshold decision.  Also remember that the parasitoid, Macroglenes penetrans (shown below), is actively searching for wheat midge at the same time.  Preserve this parasitoid whenever possible and remember your insecticide control options for wheat midge also kill these beneficial insects which help reduce midge populations.



In-field monitoring for wheat midge should be carried out in the evening (preferably after 8:30 pm or later) when the female midges are most active. On warm (at least 15ºC), calm evenings, the midge can be observed in the field, laying their eggs on the wheat heads. Midge populations can be estimated by counting the number of adults present on 4 or 5 wheat heads. Inspect the field daily in at least 3 or 4 locations during the evening.


Economic Thresholds for Wheat Midge:
  1. To maintain optimum grade: 1 adult midge per 8 to 10 wheat heads during the susceptible stage.
  2. For yield only: 1 adult midge per 4 to 5 heads. At this level of infestation, wheat yields will be reduced by approximately 15% if the midge is not controlled.
     
Inspect the developing kernels for the presence of larvae and the larval damage.


NEW – Wheat growers in Alberta can now access mapped cumulative counts from wheat midge pheromone traps.


  1. Cereal Leaf Beetles (Oulema melanopus) – Reminder – Fact sheets for Cereal leaf beetle (CLB) are posted by Alberta Agriculture and Forestry, and BC Ministry of Agriculture, and the Prairie Pest Monitoring Network.  Descriptions of the various CLB stages and some monitoring tips are included below.  
Lifecycle and Damage:
Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Refer to figure below). The thorax and legs are light orange-brown. Females (4.9 to 5.5 mm) are slightly larger than the males (4.4 to 5 mm). Adult beetles overwinter in and along the margins of grain fields in protected places such as in straw stubble, under crop and leaf litter, and in the crevices of tree bark. They favour sites adjacent to shelterbelts, deciduous and conifer forests. They emerge in the spring once temperature reaches 10-5ºC and are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals. 


Egg: Eggs are laid approximately 14 days following the emergence of the adults. Eggs are laid singly or in pairs along the mid vein on the upper side of the leaf and are cylindrical, measuring 0.9 mm by 0.4 mm, and yellowish in colour. Eggs darken to black just before hatching. 


Larva: The larvae hatch in about 5 days and feed for about 3 weeks, passing through 4 growth stages (instars). The head and legs are brownish-black; the body is yellowish. Larvae are usually covered with a secretion of mucus and fecal material, giving them a shiny black, wet appearance (Refer to figure below).  When the larva completes its growth, it drops to the ground and pupates in the soil.


Pupa: Pupal colour varies from a bright yellow when it is first formed, to the colour of the adult just before emergence. The pupal stage lasts 2 – 3 weeks. Adult beetles emerge and feed for a couple of weeks before seeking overwintering sites. There is one generation per year.


Cereal leaf beetle adult (left) and larva (right).


Leaf damage resulting from feeding by cereal leaf beetle larvae.


Monitoring:
Give priority to following factors when selecting monitoring sites:
□  Choose fields and sections of the fields with past or present damage symptoms.
□  Choose fields that are well irrigated (leaves are dark green in color), including young, lush crops.  Areas of a field under stress and not as lush (yellow) are less likely to support CLB.
□  Monitor fields located along riparian corridors, roads and railroads.
□  Survey field areas situated near brush cover or weeds, easy to access, or are nearby sheltered areas such as hedge rows, forest edges, fence lines, etc.
Focus your site selection on the following host plant priorities:
●  First – winter wheat. If no winter wheat is present then;
●  Second – other cereal crops (barley, wheat, oats, and rye). If no cereal crops are present then;
●  Third – hay crops. If no hay crops or cereal crops are present then;
●  Fourth – ditches and water corridors


Sweep-net Sampling for Adults and Larvae:
A sweep is defined as a one pass (from left to right, executing a full 180 degrees) through the upper foliage of the crop using a 37.5 cm diameter sweep-net. A sample is defined as 100 sweeps taken at a moderate walking pace collected 4-5 meters inside the border of a field.  At each site, four samples should be collected, totaling 400 sweeps per site.  The contents of each sample should be visually inspected for life stages of CLB and all suspect specimens should be retained for identification.  Please note that, because the CLB larvae are covered in a sticky secretion, when they are caught in a sweep-net they are often covered in debris and are very difficult to see. To help determine the presence of CLB, place the contents of the sweep net into a large plastic bag for observation.


Visual Inspection:
Both the adults and larvae severely damage plants by chewing out long strips of tissue between the veins of leaves, leaving only a thin membrane. When damage is extensive, leaves turn whitish (Figure 14). The plant may be killed or the crop may be seriously reduced. In addition to feeding damage, inspectors should be looking for all life stages of the CLB. In a field of host material the visual survey should be conducted between “sweep samples”.  Other locations to be examined include grass covered ditch banks and young host crops that are too low to sweep. Experienced surveyors should spend 15 minutes on visual inspection. Less experience surveyors should spend an additional 10 minutes on the visual component.


  1. Swede midge (Contarinia nasturtii) – Reminder – This season we again include scouting tips for in-field monitoring:
□  Watch for unusual plant structures and plant discolourations then follow-up by closely scrutinizing the plant for larvae (Refer to Figure below).
□  The growing tip may become distorted and produce several growing tips or none at all, young leaves may become swollen, crinkled or crumpled and brown scarring caused by larval feeding may be seen on the leaf petioles and stems.
□  Flowers may fail to open.
□  Young plants that show unusual growth habits should be examined carefully for damage and larvae, especially if the sticky liners have many flies resembling midges (swede midges are about the size of orange blossom wheat midge but are not orange).
□  Larvae can be seen with a hand lens.



In 2014, Canola School posted a swede midge update entitled “ Swede midge a pest on the rise”, featuring Dr. Julie Soroka (AAFC-Saskatoon).  The Ontario Canola Growers post swede midge information here.  Dr. Rebecca Hallett has posted a very helpful swede midge identification guide for those performing in-field monitoring and pheromone trapping.  Finally, canola management recommendations for swede midge in Ontario are posted by Rebecca Hallett and Brian Hall.


  1. Cabbage seedpod weevil (Ceutorhynchus obstrictus) –  There is one generation of CSPW per year and the overwintering stage is the adult which is an ash-grey weevil measuring 3-4mm long (Refer to lower left photo).  Adults typically overwinter in soil beneath leaf litter within shelter belts and roadside ditches.  They emerge from overwintering in the spring as soil temperatures warm to ~15°C.  CSPW utilize several flowering hosts including wild mustard, flixweed, hoary cress, stinkweed and volunteer canola.  CSPW move to canola during the bud to early flower stages and will feed on pollen and buds, causing flowers to die.  Adult feeding damage to buds is more evident in dry years when canola is unable to compensate for bud loss.  Adults mate following a pollen meal then the female will deposit a single egg through the wall of a developing pod or adjacent to a developing seed within the pod (refer to lower right photo).  Eggs are oval and an opaque white, each measuring ~1mm long.  Typically a single egg is laid per pod although, when CSPW densities are high, two or more eggs may be laid per pod.



There are four larval instar stages of the CSPW and each stage is white and grub-like in appearance ranging up to 5-6mm in length (refer to lower left photo).  The first instar larva feeds on the cuticle on the outside of the pod while the second instar larva bores into the pod, feeding on the developing seeds.  A single larva consumes about 5 canola seeds.  The mature larva chews a small, circular exit hole from which it drops to the soil surface and pupation takes place in the soil within an earthen cell.  Approximately 10 days later, the new adult emerges to feed on maturing canola pods.  Later in the season these new adults migrate to overwintering sites beyond the field.  


Monitoring:  Begin sampling when the crop first enters the bud stage and continue through the flowering. Sweep net samples should be taken at ten locations within the field with ten 180° sweeps per location. Count the number of weevils at each location. Samples should be taken in the field perimeter as well as throughout the field.  Adults will invade fields from the margins and if infestations are high in the borders, application of an insecticide to the field margins may be effective in reducing the population to levels below which economic injury will occur.  An insecticide application is recommended when three to four weevils per sweep are collected and has been shown to be the most effective when canola is in the 10 to 20% bloom stage (2-4 days after flowering starts). Consider making insecticide applications late in the day to reduce the impact on pollinators.  Whenever possible, provide advanced warning of intended insecticide applications to commercial beekeepers operating in the vicinity to help protect foraging pollinators.  High numbers of adults in the fall may indicate the potential for economic infestations the following spring. 


Please find additional detailed information for CSPW in fact sheets posted by Alberta Agriculture and Forestry, Saskatchewan Agriculture, or the Prairie Pest Monitoring Network.




  1. Cabbage root maggot (Delia spp.) – Among root feeding pests of canola, historically five species of Delia flies have been identified across the Canadian prairies;  Delia radicum (L.), D. floralis (Fallén), D. platura (Meigan), D. planipalpis (Stein), and D. florilega (Zett.) have been observed in canola over 30 years of research (Liu and Butts 1982, Griffiths 1986a, Broatch and Vernon 1997; Soroka and Dosdall 2011).  A summary of root maggot biology, research, and pest management recommendations for canola production was published by Soroka and Dosdall (2011).  



Root maggots continue to be a problematic in canola production largely owing to the fact that (i) the species is composition varies by geographic latitude and local conditions, plus (ii) one or two generations per year will occur but varies by species.  The species complex is typically characterized by multiple, overlapping generations of Delia resulting in adults laying eggs in canola (Refer to upper left photo for adult and eggs) from late Spring to October and maggots feeding on roots from late rosette until late fall (Refer to upper right photo).  Root maggots pupate and overwinter within cigar-shaped, reddish-brown puparia 5-20 cm below the soil surface (Soroka and Dosdall 2011) so canola-on-canola rotations should be avoided.  In the spring, adults emerge from mid-May to mate and females lay oval, white eggs singly or in batches near the base of cruciferous host plants over a 5-6 week period.  The larvae develop through three instar stages which feed on root hairs then secondary roots initially whereas older maggots will feed into the taproot of a canola plant.  


Remember there is no registered insecticide for root maggot control in canola.




  1. Lygus bugs (Lygus spp.) – The economic threshold for Lygus in canola is applied at late flower and early pod stages.  Biological and monitoring information can be linked by clicking here or you can access the Manitoba, or Alberta fact sheets or the Prairie Pest Monitoring Network’s monitoring protocol.  


Adult Lygus Bug
Adult L. lineolaris (5-6 mm long) (photo: AAFC-Saskatoon).


Lygus Bug Nymph
Fifth instar lygus bug nymph (3-4 mm long) (photo:  AAFC-Saskatoon).


Damage: Lygus bugs have piercing-sucking mouthparts and physically damage the plant by puncturing the tissue and sucking plant juices. The plants also react to the toxic saliva that the insects inject when they feed. Lygus bug infestations can cause alfalfa to have short stem internodes, excessive branching, and small, distorted leaves. They feed on buds and blossoms and cause them to drop. They also puncture seed pods and feed on the developing seeds causing them to turn brown and shrivel.
Begin monitoring canola when it bolts and continue until seeds within the pods are firm. Since adults can move into canola from alfalfa, check lygus bug numbers in canola when nearby alfalfa crops are cut.
Sample the crop for lygus bugs on a sunny day when the temperature is above 20°C and the crop canopy is dry. With a standard insect net (38 cm diameter), take ten 180° sweeps. Count the number of lygus bugs in the net.
Repeat the sampling in another 14 locations. Samples can be taken along or near the field margins. Calculate the cumulative total number of lygus bugs and then consult the sequential sampling chart (Figure C). If the total number is below the lower threshold line, no treatment is needed. If the total is below the upper threshold line, take more samples. If the total is on or above the upper threshold line, calculate the average number of lygus bugs per 10-sweep sample and consult the economic threshold table.
Sequential Sampling for Lygus Bug at Late Flowering Stage
Sequential sampling for lygus bugs at late flowering stage in canola.


The economic threshold for lygus bugs in canola covers the end of the flowering (Table 1) and the early pod ripening stages (Table 2). Once the seeds have ripened to yellow or brown, the cost of controlling lygus bugs may exceed the damage they will cause prior to harvest, so insecticide application is not warranted.
Consider the estimated cost of spraying and expected return prior to making a decision to treat a crop.  Remember that insecticide applications at bud stage in canola have not been proven to result in an economic benefit in production.  The exception to this is in the Peace River region where early, dry springs and unusually high densities of lygus bug adults can occasionally occur at bud stage.  In this situation, high numbers of lygus bugs feeding on moisture-stressed canola at bud stage is suspected to result in delay of flowering so producers in that region must monitor in fields that fail to flower as expected.
Table 1.  Economic thresholds for lygus bugs in canola at late flowering and early pod stages (Wise and Lamb 1998).


1 Canola crop stage estimated using Harper and Berkenkamp 1975).
2 Economic thresholds are based on an assumed loss of 0.1235 bu/ac per lygus bug caught in 10 sweeps (Wise and Lamb. 1998. The Canadian Entomologist. 130: 825-836).


Table 2.  Economic thresholds for lygus bugs in canola at pod stage (Wise and Lamb 1998).


3 Economic thresholds are based on an assumed loss of 0.0882 bu/ac per lygus bug caught in 10 sweeps (Wise and Lamb. 1998. The Canadian Entomologist. 130: 825-836).


  1. Provincial Insect Pest Updates – The following provincial websites have their pest updates posted so click the links to access their reports:
●  Manitoba’s Insect and Disease Report  (July 7, 2015)
●  Saskatchewan’s Insect Update (July 7, 2015)
●  Alberta’s Insect Update (Call of the Land audio report of July 16, 2015)


  1. Insect of the Week – Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Field Guide (2015) by Hugh Philip is a new publication from Agriculture and Agri-Food CanadaThis growing season we will post an “Insect of the Week” in the form of short excerpts from the field guide. This week features several species of aphids (i.e., corn leaf, English grain, green peach, oat-birdcherry, pea, potato, soybean, turnip, greenbug).



Additionally, ladybird beetles were also featured in the Insect of the Week.



  1. Crop Reports –  The following provincial websites now have their Crop Reports posted so click the links to find their weekly updates:




  1. West Nile Virus Risk – Reminder – Now is the time for DEET!  The regions most advanced in degree-day accumulations for Culex tarsalis, the vector for West Nile Virus, are shown in the map below.  Areas yet to be highlighted in red on the map below will have accumulated sufficient heat for C. tarsalis to fly. As of July 12, 2015, the predicted development of C. tarsalis is most advanced in the southern areas of our prairie provinces with adults predicted to emerge from 350-400 DD in the map below ( will be highlighted in red).


The Public Health Agency of Canada posts information related to West Nile Virus in Canada and their website is located here.  The Canadian Wildlife Health Cooperative compiles and posts information related to their disease surveillance.  As of this week, one bird in New Brunswick and one bird in Ontario tested positive for West Nile-related deaths (click here to view the report).





  1. Questions or problems accessing the contents of this Weekly Update?  Please e-mail or call either Owen.Olfert@agr.gc.ca (tel. 306-385-9355) or Jennifer.Otani@agr.gc.ca (tel. 780-354-5132).  Past and present “Weekly Updates” are very kindly posted to the Western Forum website by webmaster, Dr. Kelly Turkington.  Please click here to link to that webpage.
  1. Previous topics:
    1. The PPMN Blog is located at http://PrairiePestMonitoring.blogspot.ca   Subscribe to receive the most current information OR bookmark the site to visit later.
    2. Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide – The NEW Field Guide to Support Integrated Pest Management (IPM) in Field and Forage Crops is NOW available for download from www.publications.gc.ca.   Two downloadable (~8 MB) versions of the complete field guide are available as either a  ‘Regular’ (i.e., best for printing: EnglishFrench) or ‘Enhanced’ (i.e., best for viewing electronically with active internal and external hyperlinks: English-enhancedFrench-enhanced).
    3. Wind trajectories Related to Diamondback Moth (DBM) and Aster Leafhopper Introductions – Completed for the season.  Please refer to earlier Weekly Updates for details related to backward and forward trajectories associated with air parcels moving over western Canadian locations.
    4. Flea Beetles (Chrysomelidae: Phyllotreta species) – Helpful images produced by Dr. Julie Soroka (AAFC-Saskatoon) exemplifying percent of cotyledon leaf area consumed by flea beetles are posted at Canola Watch.  
    5. Cutworms (Noctuidae) – Cutworm biology, species information, plus monitoring recommendations are available at the Prairie Pest Monitoring Network’s Cutworm Monitoring Protocol.  Also refer to these cutworm-specific fact sheets (Manitoba Agriculture and Rural Initiatives, Alberta Agriculture, Food and Rural Development).  If cutworms are spotted in Albertan fields, please also consider using the Alberta Pest Surveillance Network’s “2015 Cutworm Reporting Tool” for online reporting located by clicking here.  Data entered at that website uploads to a live “Cutworm Map”.
    6. Pea Leaf Weevil (Sitona lineatus) –Link here for the Pea leaf weevil monitoring protocol which includes photos of related weevils.
    7. Crop Protection Guides – Access Saskatchewan’s Crop Production Guide,  Manitoba’s Guide to Crop Production,  Alberta’s Crop Protection or Blue Book,  or the Western Committee on Crop Pests Guidelines for the Control of Crop Pests.
    8. Canola Insect Scouting Chart – Reminder – The Canola Insect Scouting Chart has been updated with hyperlinks now directing growers to downloadable pages from the NEW Field Guide!
    9. Alfalfa Weevil (Hypera postica) – Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).

Insect of the Week – Grasshopper

The grasshopper (Packard, clearwinged, migratory and two-striped) is this week’s Insect of the Week  (from the new Field Crop and Forage Pests and their Natural Enemies in Western Canada – Identification and Management Field Guide – download links available on the Insect of the Week page). 

Weekly Update (Update)

Today we updated the Bertha armyworm and Grasshopper sections of the Weekly Update that was originally posted on June 17, 2015!  

Please review either the Post (in HTML format) by scrolling down below and selecting it OR access a PDF copy of the updated file.

Ongoing Monitoring Efforts for 2015

In 2014, the PPMN compiled data for the following sites highlighted in the map below.  The monitoring data collected from these sites forms invaluable sources of information both now and into the future.

Agricultural people from federal, provincial, regional and industry sectors all contribute to this tremendous effort!  Monitoring at sites like these below provides crucial information on insect pest risk before and during the growing season.  Some sites are visited annually while others are checked weekly and all that data enables the synthesis and generation of risk and forecast maps like those posted here.

THANK YOU to all who contribute!
Please contact Dr. Owen Olfert at AAFC-Saskatoon for more information about this map.