Spotted wing drosophila CC BY 2.0 Oregon State University
This invasive insect is thought to have originated in southeast Asia. The first record of spotted wing drosophila (Drosophila suzukii) is from Japan in 1916. Spotted wing drosophila is now established in small and stone fruit production areas throughout North America. These insects have been found in Saskatchewan, Alberta and southern Manitoba, but more work is needed to determine if there are established populations that cause economic damage on the prairies. Spotted wing drosophila is an economic pest of many soft fruits including raspberry, strawberry, saskatoon berry, blueberry, cherry and plum.
Larval feeding causes fruit to become prematurely soft and unmarketable. Larvae mature in 3-13 days and pupate most commonly in the fruit. This feeding also increases the risk of fungal infections in the fruit like brown rot or botrytis.
Spotted wing drosophila adults are 3-4 millimetres long, with a yellow-brown body and red eyes. Males have a conspicuous spot on the leading edge of each wing. Females lack the spots but have a characteristic large, serrated egg-laying organ (ovipositor) that allows them to pierce the skin of the fruit where they lay their eggs. Larvae are white maggots that grow up to 3 millimetres long. While the larvae are tapered on both ends and have no clearly defined head, they possess two dark “mouth hooks” at the front.
Homemade spotted wing drosophila trap CC BY 2.0 Oregon State University
Biological and monitoring information related to spotted wing drosophila in field crops can be found on our Monitoring page as well as on the Manitoba Agriculture and Resource Development website.
This is Week 17 and the last Weekly Update for 2020! It’s been an exceptional field season – responding to COVID-19 and a new website for the Prairie Pest Monitoring Network! Watch for special releases during the fall and winter. Your best option is to please subscribe to the new website to stay informed.
We thank the many people who have been monitoring, collecting, compiling and generating data throughout this growing season – your exceptional efforts are appreciated and critical! We also sincerely thank the many researchers, talented technical support staff, and the many students who have contributed to agricultural field crop protection, arthropod biodiversity, and insect pest management this season!
An abbreviated synopsis is provided for the final Weekly Update of the 2020 growing season. It was a warm week for most of the prairies! The highest temperatures the past seven days across the prairies are represented in Figure 1 and ranged from <22 to >35 °C.
All those high temperatures advanced the accumulation of heat units across the prairies. The growing degree day map (GDD) (Base 5 ºC, April 1-August 17, 2020) is below (Fig. 2) while the growing degree day map (GDD) (Base 10 ºC, April 1-August 17, 2020) is shown in Figure 3.
Figure 2. Growing degree day map (Base 5 °C) observed across the Canadian prairies for the growing season (April 1-August 17, 2020). Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209Figure 3. Growing degree day map (Base 10 °C) observed across the Canadian prairies for the growing season (April 1-August 17, 2020). Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209
So far this growing season, the number of days above 25 °C ranges from 0-10 days in the northwest of the prairies then increases up to 61-70 days in southern Manitoba (Fig. 4). In comparison, the number of days above 30 °C ranges up to 25-27 days in southern Saskatchewan and southern Manitoba (Fig. 5)
Figure 4. Number of days above 25 °C observed across the Canadian prairies this growing season (April 1-August 19, 2020). Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209Figure 5. Number of days above 30 °C observed across the Canadian prairies this growing season (April 1-August 19, 2020). Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (20Aug2020). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true&reset=1588297059209
As fields continue to mature in late August and in to September, growers will be watching for cool evenings. The lowest temperatures the past seven days across the prairies are represented in Figure 6 and ranged from <1 to >13 °C.
Cumulative rainfall for the past 7 days was lowest across central and southern regions of Alberta and Saskatchewan while western and northern areas of the Peace River region AND eastern Saskatchewan plus much of Manitoba received more moisture (Fig. 7). Cumulative 30-day (Fig. 8) and rainfall for the growing season (April 1-August 19, 2020; Fig. 9) are below.
The Diamondback moth (DBM) model was run with a biofix of May 15, 2020. DBM densities generally increase with increasing numbers of generations. Figure 1 represents the model output for the 2020 growing season (as of August 17, 2020). The number of generations varies from two in western Alberta to four in southeastern Saskatchewan and most of Manitoba (Fig. 1). Next, the model was run with climate normal data to compare the 2020 growing season with an ‘average’ growing season (Fig. 2). The second map (climate normal) indicates that an average growing season results in two to three generations, with a fourth generation predicted to occur near Winnipeg (Fig. 2). These results indicate that there was an elevated DBM risk in 2020.
Figure 1. Using a biofix date of May 15, 2020, the projected number of diamondback moth (Plutella xylostella) generations across the Canadian prairies as of August 17, 2020.Figure 2. Using a biofix date of May 15, 2020, the projected number of diamondback moth (Plutella xylostella) generations across the Canadian prairies as of August 17, 2020, using climate normal data.
The 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).
Monitoring to apply the economic threshold: 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 (Fig. 3) dislodged from the plant. Repeat this procedure at least in five locations in the field to get an accurate count.
Figure 3. Diamondback larva measuring ~8mm long. Note brown head capsule and forked appearance of prolegs on posterior.Figure 4. Diamondback moth pupa within silken cocoon.Figure 5. Diamondback moth.
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.
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.
Cool, wetter growing seasons generally favour wheat midge development. Wheat midge larvae overwinter in the soil in larval cocoons. Adequate soil moisture (May-June) is required to terminate diapause, resulting in movement of larvae to the soil surface. The wheat midge model was run to determine potential numbers of overwintering wheat midge larvae.
During May and June weather conditions were cooler and wetter than normal across most of Alberta. These model runs indicated that weather conditions that would promote diapause termination and movement of larvae to the soil surface were favourable, and may have resulted in higher than average adult populations in early July. Conversely, warm, dry conditions occurred across most of Manitoba and were not suitable for larval development during May and June. Figure 1 represents the potential number of larval cocoons (as of August 17, 2020). Densities of wheat midge larval cocoons were predicted to be greater across Alberta than Saskatchewan and Manitoba (Fig. 1). Figure 2 provides a comparison of densities for the same time period in 2019. Low densities in 2019 were attributed to well below normal precipitation during the period of April to June (Fig. 2).
Figure 1. Predicted number of larval cocoons of wheat midge (Sitodiplosis mosellana) across the Canadian prairies as of August 17, 2020.Figure 2. Predicted number of larval cocoons of wheat midge (Sitodiplosis mosellana) across the Canadian prairies as of August 17, 2019.
Review information supporting in-field monitoring for wheat midge (Fig. 3) and its parasitoid, Macroglenes penetrans (Fig. 4), posted back on Week 14 of the 2020 growing season.
Figure 3. Wheat midge (Sitodiplosis mosellana) laying their eggs on the wheat heads (Photo: AAFC-Beaverlodge-S. Dufton & A. Jorgensen).Figure 4. Macroglenes penetrans, a parasitoid wasp that attacks wheat midge, measures only ~2 mm long. (Photo: AAFC-Beaverlodge-S. Dufton).
More information about Wheat midge can be found by accessing the pages from the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Field Guide”. View ONLY the Wheat midge pages but remember the guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.
As of August 17, 2020, the Pea leaf weevil (PLW) model indicates that pupation is complete and adults are beginning to emerge from pea fields. The PLW model predicts that warm, dry conditions in June and early July may reduce larval survival. Wetter conditions during June and July were more favourable for PLW population development in Alberta than in eastern Saskatchewan and Manitoba. These factors resulted in lower overwintering adult index values for the eastern prairie region than for western regions (Fig. 1). Figure 2 represents the expected overwintering index values for PLW using climate normal data. Note that, to our knowledge, populations of pea leaf weevil remain low in Manitoba and are confined to the Swan River Valley region at this time.
Figure 1. The predicted overwintering adult index of pea leaf weevil (Sitona lineatus) across the Canadian prairies as of August 17, 2020.Figure 2. The predicted overwintering adult index of pea leaf weevil (Sitona lineatus) across the Canadian prairies as of August 17, 2020, using climate normal data.
The pea leaf weevil is a slender greyish-brown insect measuring approximately 5 mm in length (Fig. 3, Left image). Pea leaf weevil resembles the sweet clover weevil (Sitona cylindricollis) but the former is distinguished by three light-coloured stripes extending length-wise down thorax and sometimes the abdomen. All species of Sitona, including the pea leaf weevil, have a short snout.
Figure 3. Comparison images and descriptions of four Sitona species adults including pea leaf weevil (Left).
Review a more complete description of this insect posted back on Week 11 of the 2020 growing season. Biological and monitoring information related to pea leaf weevil in field crops is posted by the province of Alberta and in the PPMN monitoring protocol.
The following is offered to predict when Culex tarsalis, the vector for West Nile Virus, will begin to fly across the Canadian prairies (Fig. 1). This week, regions most advanced in degree-day accumulations for Culex tarsalis are shown in Figure 1. As of August 16, 2020 (Fig. 1), areas highlighted yellow and more imminently orange are approaching sufficient heat accumulation for mosquitoes to emerge. Areas highlighted red NOW HAVE Culex tarsalis flying (Fig. 1) – protect yourself by wearing DEET!
Figure 1. Predicted development of Culex tarsalis across the Canadian prairies (as of August 16, 2020).
Reminder – The Canadian Grain Commission is ready to grade grain samples harvested in 2020. Samples are accepted up to November 30 but growers normally send samples as soon as harvest is complete.
This is a FREE opportunity for growers to gain unofficial insight into the quality of grain and to obtain valuable dockage information and details associated with damage or quality issues. The data collected also helps Canada market its grain to the world!
More information on the Harvest Sample Program is available at the Canadian Grain Commission’s website where growers can register online to receive a kit to submit their grain.
In exchange for your samples, the CGC assesses and provides the following unofficial results FOR FREE:
unofficial grade
dockage assessment on canola
protein content on barley, beans, chick peas, lentils, oats, peas and wheat
oil, protein and chlorophyll content for canola
oil and protein content and iodine value for flaxseed
oil and protein for mustard seed and soybean
Falling Number for wheat
Vomitoxin (deoxynivalenol or DON) for wheat and corn.
It can be helpful to have grade and quality information on samples before delivering their grain. Read brochures produced by the Canadian Grain Commission describing the Harvest Sample Program and details specific to the Western version of the program.
Reminder – Entomologists with Agriculture and Agri-Food Canada in Winnipeg are doing a survey in September of insects in farm grain bins. They are looking for 10 farms not far from Winnipeg where they can access grain bins to sample insects. No grain will be removed, just insects. If interested, please contact John Gavloski (John.Gavloski@gov.mb.ca) as soon as possible.
Provincial entomologists provide insect pest updates throughout the growing season so link to their information:
• Manitoba‘s Crop Pest Updates for 2020 are available. Access the August 18 2020 report. The summary indicates that, “Grasshoppers continue to be the insect of greatest concern. Some have also commented on the high levels of flea beetles being observed in canola currently.”
• Alberta Agriculture and Forestry’s Agri-News occasionally includes insect-related information or Twitter users can connect to #ABBugChat Wednesdays at 10:00 am.
This week’s Insect of the Week feature crop is soybean, a common crop in Eastern Canada that has become more popular in the Prairie region over the past decade.
Soybeans – AAFC
Despite being a recent crop to Western Canada, soybean cultivation in Alberta, Saskatchewan and Manitoba contributed 20% to the national production total in 2019. Ongoing research is being conducted to develop new plant varieties that are better suited to the short growing season and low temperatures characteristic to the Canadian Prairies. In 2019, soybeans where seeded over 658,200 hectares (1.6 million acres) across the Prairie Region, producing 1.2 million metric tonnes (almost 1.4 million US tons).
This past week (July 22-28, 2019) temperatures were approximately 2 °C warmer than last week (Fig. 1). The warmest temperatures were observed in MB and southern AB while temperatures were cooler in western AB and the Peace River region.
Figure 1. Average temperature (°C) across the Canadian prairies the past seven days (July 22-28, 2019).
Across the prairies, 30-day (June 28 – July 28, 2019) average temperatures have been approximately 1 °C cooler than normal (Fig. 2). Temperatures were warmest across MB and eastern SK.
Figure 2. Average temperature (°C) across the Canadian prairies the past 30 days (June 28-July 28, 2019).
Growing season temperatures (April 1-July 28, 2019; Fig. 3) in AB and SK have been 1 °C cooler than average while central and eastern MB has been approximately 1 °C warmer than average (Fig. 4).
Figure 3. Average temperature (°C) across the Canadian prairies for the growing season (April 1-July 28, 2019).Figure 4. Mean temperature difference (°C) from Normal observed across the Canadian prairies for the growing season (April 1-July 31, 2019). Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (01Aug2019). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
This past week significant rainfall amounts were reported the parkland region of SK and AB (Fig. 5). Across the prairies, rainfall amounts for the past 30 days have been highly variable (Fig. 6).
Figure 5. Cumulative precipitation observed the past seven days across the Canadian prairies (July 22-28, 2019).Figure 6. Cumulative precipitation observed the past 30 days across the Canadian prairies (June 28-July 28, 2019).
Dryer conditions continue across southern AB and western SK. Growing season (April 1 – July 21, 2019; Fig. 7) rainfall amounts have been below average across southern regions of AB, and across MB (Fig. 8).
Figure 7. Cumulative precipitation observed for the growing season (April 1-July 28, 2019) across the Canadian prairies.Figure 8. Percent of average precipitation observed across the Canadian prairies for the growing season (April 1-July 31, 2019). Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (01Aug2019). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
The growing degree day map (GDD) (Base 5 ºC, April 1-July 21, 2019) is below (Fig. 9):
The growing degree day map (GDD) (Base 10 ºC, April 1-July 21, 2019) is below (Fig. 10):
The lowest temperatures (°C) observed the past seven days ranged from at least 12 down to at least 0 °C in the map below (Fig. 11).
Figure 11. Lowest temperatures (°C) observed across the Canadian prairies the past seven days (to July 31, 2019). Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (01Aug2019). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
The highest temperatures (°C) observed the past seven days ranged from at least 18 up to at least 32 °C in the map below (Fig. 12).
Figure 12. Highest temperatures (°C) observed across the Canadian prairies the past seven days (to July 31, 2019). Image has not been reproduced in affiliation with, or with the endorsement of the Government of Canada and was retrieved (01Aug2019). Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true
The maps above are all produced by Agriculture and Agri-Food Canada. Growers can bookmark the AAFC Drought Watch Maps for the growing season.
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!
Wheat Midge (Sitodiplosis mosellana) – Reminder – Based on fall surveys in 2018, wheat midge populations were expected to be low across most of AB and SK this season. Dry conditions in May and June have resulted in reduced emergence of adult populations across most of SK.
Review last week’s predictive model update (Wk 16) regarding the development for this pest. This week, the percent of adult emergence is depicted across the Canadian prairies as of July 28, 2019 (Fig. 1). 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. Midge emergence is 100% complete in areas highlighted red, 90% complete in areas highlighted orange, and ≤50% in areas highlighted light orange or yellow (Fig. 1).
Figure 1. Accumulation of heat units necessary for wheat midge (Sitodiplosis mosellana) to emerge from puparia in the soil and corresponding estimated percent of midge emerged across the Canadian prairies as of July 28, 2019.
Monitoring: When monitoring wheat fields, pay attention to the synchrony between flying midge and anthesis.
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 (photographed by AAFC-Beav-S. Dufton & A. Jorgensen below). 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.
REMEMBER that in-field counts of wheat midge per head remain the basis of economic threshold decision. Also remember that the parasitoid, Macroglenes penetrans (photographed by AAFC-Beav-S. Dufton 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.
Economic Thresholds for Wheat Midge: a) To maintain optimum grade: 1 adult midge per 8 to 10 wheat heads during the susceptible stage. b) 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.
Wheat midge and its doppelganger, the lauxanid fly, were featured as the Insect of the Week (for Wk10). Check that post for help with in-field scouting for this economic pest of wheat! The differences between midges and parasitoid wasps are featured as the current Insect of the Week (for Wk11). Not all flying insects are mosquitoes nor are they pests – many are important parasitoid wasps that actually regulate insect pest species in our field crops.
More information about Wheat midge can be found by accessing the pages from the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Field Guide”. View ONLY the Wheat midge pages but remember the guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.
Bertha armyworm (Lepidoptera: Mamestra configurata) – Predictive model updates are completed for the growing season but can be reviewed here (Wk 14).
Important – Watch for updates from your provincial monitoring networks who are compiling cumulative pheromone-baited trap interceptions to assess risk levels in Alberta, Saskatchewan (updated 24Jul2019), and Manitoba (locate table on pg 6). regions in all three prairie provinces are reporting “uncertain” risk based on pheromone-baited unitrap cumulative counts.
This week – SCOUT NOW to confirm in-field larval counts and REMEMBER that LARVAL DENSITIES CAN VARY DRAMATICALLY even between adjacent fields! Scout to protect @FieldHeroes and avoid economic losses! Use the Field Heroes’ scouting guide for bertha armyworm and be sure to read more at their website!
Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of Manitoba, Saskatchewan, Alberta and the Prairie Pest Monitoring Network. Also refer to the bertha armyworm pages within the “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.
Refer to the PPMN Bertha armyworm monitoring protocol for help when performing in-field scouting. Use the images below (Fig. 1) to help identify egg masses and the economically important larvae in canola.
Figure 1. Stages of bertha armyworm from egg (A), larva (B), pupa (C) to adult (D). Photos: J. Williams (Agriculture and Agri-Food Canada).
Now is the time to do in-field scouting for this insect pest. Review the Insect of the Week which features bertha armyworm and its doppelganger, the clover cutworm!
The economic threshold for Lygus in canola is applied at late flower and early pod stages.
Adult L. lineolaris (5-6 mm long) (photo: AAFC-Saskatoon).
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.
Scouting tips to keep in mind: 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.
Sampling becomes more representative IF repeated at multiple spots within a field. For lygus bug monitoring, sampling is most accurate when repeated at a total of 15 spots within the field. 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 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).
Biological and monitoring information related to Lygus in field crops is posted by the provinces of Manitoba or Alberta fact sheets or the Prairie Pest Monitoring Network’s monitoring protocol. Also refer to the Lygus pages within the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” – both English or French versions are available.
Reminder – One last time for this growing season….. We have updated the field scouting charts so they now link to pages within the 2018 version of the Insect Field Guide.
We offer TWO generalized insect pest scouting charts to aid in-field scouting on the Canadian prairies:
Whenever possible, monitor and compare pest densities to established economic or action thresholds to protect and preserve pollinators and beneficial arthropods. Economic thresholds, by definition, help growers avoid crop losses related to insect pest species but they rely on in-field scouting!
The following is offered to predict when Culex tarsalis will begin to fly across the Canadian prairies (Fig. 1). Protect yourself by wearing DEET! This week, regions most advanced in degree-day accumulations for Culex tarsalis, the vector for West Nile Virus, are shown in the map below. As of July 28, 2019, areas highlighted orange are on the verge of approaching sufficient heat accumulation for mosquitoes to emerge. Areas highlighted red in the map below should now have C. tarsalis in flight.
Figure 1. Predicted development of Culex tarsalis, across the Canadian prairies (as of July 28, 2019).
Once adults emerge, the following map demonstrates how quickly a Culex tarsalis mosquito carrying WNV can become fully infective (i.e., when it has accumulated 109 base 14.3° degree days) – it’s a matter of days, depending on the region (Figure 2). For example, as of July 28, 2019, Altona MB is predicted to only take 16 days for C. tarsalis to become fully infective!
Provincial entomologists provide insect pest updates throughout the growing season so we link to their most recent information:
• Manitoba‘s Crop Pest Updates for 2019 are posted here. Access Issue #11 posted July 31, 2019, noting continued grasshopper issues, presence of some diamondback larvae and bertha armyworm pheromone trap interception counts that warranting in-field scouting in several regions of that province. There is also a call and link for Manitoban cooperators to perform the annual grasshopper counts. This a vital survey which contributes to the annual grasshopper forecast maps that growers depend upon to help assess risk.
Public summer field events – Coming to a field near you – Prairie field crop entomologists are already scheduled to be at these 2019 field tour events from May-August (be sure to re-confirm dates and details as events are finalized):
August 8, 2019: 2019 Wheatstalk to be held at Teepee Creek AB. View event info/registration details. Entomologists tentatively participating: Jennifer Otani, Shelby Dufton, Amanda Jorgensen, Boyd Mori.
August 8, 2019. Horticulture School. Agriculture and Agri-Food Canada Research Farm, Portage la Prairie, Manitoba. View event info/registration details. Entomologist presenting: John Gavloski, Kyle Bobiwash.
The case of the Monarch butterfly vs. Painted Lady butterfly (also Viceroy butterfly) An orange butterfly fluttered by. Was it a Monarch butterfly (Danaus plexippus)? Or a Painted Lady butterfly (Vanessa cardui)? If it’s a Monarch, it is species of Special Concern listed under the Species at Risk Act and is not a crop pest. Instead, it’s larvae feed solely on milkweed (Asclepias spp.), typically found in wetland areas. Painted Lady larvae, on the other hand, feed on a wider range of plants including sunflower, canola, mustard, borage, soybean, Canada thistle, burdock, knapweed, wormwood and many other plant species. While neither species overwinter in Canada, Monarchs have regular migratory routes into Canada from Mexico through the USA; Painted Ladies are accidental tourists that are on occasion blown up from the US. One important distinguishing characteristic is the distinct black band with white dots that outline the wings of Monarchs. Painted Ladies do not have this band; instead they have thin white markings along the scalloped wing edges.
Monarch butterfly (Danaus plexippus) cc by sa 3.0 Kenneth Dwain Harrelson Painted Lady butterfly (Vanessa cardui) cc by 3.0 Jean-Pol Grandmont Viceroy butterflies (Limenitis archippus) cc by 2.0 Benny Mazur
Viceroy butterflies (Limenitis archippus) are even more difficult to tell from Monarchs. Viceroys are smaller than Monarchs and sport a black line running through the middle (side-to-side) of the hindwing. Like the Monarch, Viceroys are not crop pests as their larvae feed exclusively on trees of the willow family (willow, poplar, cottonwood). For more information about Painted Lady butterflies, see the Insect of the Week page and our posts on the annual Monarch butterfly migration. 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.
Welcome to the final Weekly Update of the 2017 growing season!
We wish everyone ‘Good Luck’ with the rest of the growing season and thank the many people who have been busy monitoring in fields! The provincial entomologists, their many staff and cooperators, plus our AAFC Staff are all thanked for their ongoing efforts! Watch the Blog for the annual risk and forecast maps in January and the Weekly Updates will be back in 2018.
Weather synopsis – Temperature – Crops continue to mature and some fields have been harvested across the prairies. The map below reflects the number of days above 25°C (Fig. 1) while the next map reflects the number of days above 30°C (Fig. 2).
Figure 1. Number of days above 25°C.
Figure 2. Number of days above 30°C.
The map below reflects the highest temperatures across the prairies the past seven days (Fig. 3) while the lowest temperatures the past seven days reveals some cool nights in some areas (Fig. 4).
Figure 3. Highest temperatures the past seven days (August 15-21, 2017) across
the Canadian prairies.
Figure 4. Lowest temperatures the past seven days (August 15-21, 2017) across the Canadian prairies.
Precipitation – Seven-day rainfall accumulations were greatest in central Alberta into Saskatchewan but also in eastern Saskatchewan and into Manitoba (Fig. 5).
Figure 5. Accumulated precipitation the past seven days (August 15-21, 2017).
The accumulated precipitation for the growing season (Fig. 6) continues to reflect dryer growing conditions and dryer than normal for most of the prairies (Fig. 7).
Figure 6. Accumulated precipitation for the growing season (April 1-21, 2017).
Figure 7. Percent of average precipitation for the growing season (April 1-August 21, 2017).
The growing degree day map (GDD) (Base 10ºC, March 1 – August 20, 2017) is below:
The growing degree day map (GDD) (Base 5ºC, March 1 – August 20, 2017) is below:
The maps above are all produced by Agriculture and Agri-Food Canada. Growers may wish to bookmark the AAFC Drought Watch Maps for the growing season.
Wheat surveying – As wheat is harvested, monitoring can begin for two wheat pests including wheat midge and wheat stem sawfly. As soon as the combine passes through, in-field monitoring can commence with: ● Soil core sampling is used to assess the densities of wheat midge cocoons set to overwinter, PLUS ● The number of cut stems can be counted to determine the density of wheat stem sawfly.
By January, forecast and risk maps summarizing surveying efforts for the above pests will be available (e.g., check the Risk Map Page).
More information about these pests can be found by accessing the pages from the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Field Guide”. View ONLY the Wheat midge pages or ONLY the Wheat stem sawfly pages. Remember the entire guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.
Across the Canadian prairies, crop reports are produced by: • Manitoba Agriculture, Rural Development (August 21, 2017) • Saskatchewan Agriculture Crop Report (August 15-21, 2017)
• Alberta Agriculture and Forestry Crop Report (August 18, 2017)
The Canadian Grain Commission is ready and willing to grade grain samples harvested in 2017. Samples are accepted up to November but send samples as soon a harvest is complete. This is a FREE opportunity for growers to gain unofficial insight into the quality of their grain and to obtain valuable dockage information and details associated with damage or quality issues. The data collected also helps Canada market its grain to the world! More information on the Harvest Sample Program is available at the Canadian Grain Commission’s website where growers can register online to receive a kit to submit their grain.
In exchange for your samples, the CGC assesses and provides the following unofficial results FOR FREE:
dockage assessment on canola
unofficial grade
protein content on barley, beans, chick peas, lentils, oats, peas and wheat
oil, protein and chlorophyll content for canola
oil and protein content and iodine value for flaxseed
oil and protein for mustard seed and soybeans
Many producers find having both grade and quality information on their samples before delivering their grain to be helpful.
West Nile Virus Risk – The regions most advanced in degree-day accumulations for Culex tarsalis, the vector for West Nile Virus, are shown in the map below. As of August 20, 2017, areas highlighted in red on the map below have accumulated sufficient heat for C. tarsalis to fly. Culex tarsalis are also flying in areas highlighted in red, pink or mauve so wear your DEET to stay protected! Areas highlighted orange or yellow in the map should also be preparing for C. tarsalis flight.
The Canadian Wildlife Health Cooperative compiles and posts information related to their disease surveillance for West Nile Virus in birds. As of August 24, 2017, 1218 birds were examined and 58 tested positive for West Nile virus; three from Saskatchewan, two from Manitoba, 15 from Ontario, and 38 from Quebec. The Public Health Agency of Canada also monitors and posts updates on the status of WNV in Mosquitoes. As of August 12, 2017, Quebec, Ontario, Manitoba and Saskatchewan reported positive mosquito pools for West Nile Virus.
A total of 224 positive mosquito pools have been found:
172 from Ontario[Brant County (2), Chatham-Kent (3), Durham Region (4), Eastern Ontario (3), Halton Region (15), Hamilton (4), Haliburton-Kwartha-Pine Ridge District (1), Hastings and Prince Edward Countries (7), Kingston-Frontenac and Lennox and Addington (2), Lambton (1), Middlesex-London (3), Niagara Region (7), Ottawa (11), Oxford County (1), Peel (40), Perth District (2), Peterborough County-City (1), Renfrew County and District (2), Simcoe Muskoka District (1), Toronto (31), Waterloo (2), Wellington-Dufferin-Guelph (2), Windsor-Essex County (21), and York Regional (6)];
35 from Manitoba[(Winnipeg (12), Southern (4), Interlake Eastern (5), and Prairie Mountain (12)];
9 from Quebec[Montérégie (6), Laval (1), and Mauricie-centre-du-Québec(2)];
Upcoming Meetings and Conferences – The following agricultural insect pest-related meetings and conferences will be held – be sure to re-confirm dates and details as events are finalized: • September 28-30, 2017: The Entomological Society of Alberta Annual Meeting will be held at Crowsnest Pass AB and information is available at: https://goo.gl/UN3ZN2 • October 22-25, 2017: The Entomological Society of Canada-Entomological Society of Manitoba 2017 Joint Annual Meeting will be held at Winnipeg MB and information is available at: https://goo.gl/6RC6HC • October 25-27, 2017: The Western Forum on Pest Management will be held at the Fairmont in Winnipeg MB and information is available at: https://goo.gl/Rf4T8G • November 5-8, 2017: The Entomological Society of America meets at Denver CO and information is available at: http://www.entsoc.org/am/fm/index
• November 7-8, 2017: The Pulse and Soybean Agronomy Workshop will be held at Prairieland Park in Saskatoon SK. More information is available on their website and view the agenda or register online.
• TBA: Refer to the Entomological Society of Saskatchewan’s website for upcoming events. Information will be posted at: http://www.entsocsask.ca/events.html • November 20-23, 2017: The Canadian Weed Science Society meets at Saskatoon SK and more information is available at http://weedscience.ca/meeting-home/ • December 5-7, 2017: The Canola Meeting & Canola Innovation Day, and the Canola Discovery Forum have united to create the first ever CanolaWeek in Saskatoon SK and more information is available at https://event-wizard.com/CanolaWeek2017/0/welcome/ • January 9-10, 2018: Agronomy Update 2018 will be held in Red Deer AB at the Sheraton Hotel so watch for information to be posted at http://www.agric.gov.ab.ca/app55/events
• January 9-10, 2018: CropSphere Agricultural Conference will be held at TCU Place in Saskatoon SK during Crop Production Week. More information is available at: https://www.cropsphere.com/index.cfm with registration opening Nov 1st! • January 16-18, 2018: The Manitoba Ag Days show will be held at the Keystone Centre in Brandon MB. More information will be available at: https://www.agdays.com/ • January 16-19, 2018: The Association of Alberta Agricultural Fieldmen will hold the 2018 Provincial ASB Conference in Grande Prairie AB. More information will be available at https://aaaf.ab.ca/asb-boards/asb-conference.htmlor use links provided by Alberta Agriculture & Forestry. • January 30-February 1, 2018: FarmTech 2018 will be held in Edmonton AB and information is available at http://farmtechconference.com/ with registration typically opening early in November. • March 19-22, 2018: The 9th International IPM Symposium will be held in Baltimore MA and information is available at https://ipmsymposium.org/2018/
• November 11-14, 2018: The Joint meeting of the Entomological Society of Canada and Entomological Society of America meets in Vancouver BC and more information will be available at http://www.entsoc.org/event-calendar/entomology-2018
Provincial entomologists provide insect pest updates throughout the growing season so we have attempted to link to their most recent information:
● Manitoba’s Insect and Disease Update for 2017 is prepared by John Gavloski and Pratisara Bajracharya and read Issue #13 (posted August 16, 2017) notingsoybean aphids as field near the R6 stage and high levels of bertha armyworm larvae from some fields in western Manitoba.
● Watch for Alberta Agriculture and Forestry’s Call of the Land and access the most recent Insect Update (August 24, 2017) provided by Scott Meers. That report describes wheat stem sawfly surveying underway that scouts for cut stems to assess risk for 2018, white fluff balls at the top of canola that are actually parasitoid puparia or soon-to-be beneficial wasps that attack then emerge from a lepidopteran host, and the emergence of new-season red turnip beetles that will overwinter this fall.
This week’s Insect of the Week is the brown marmorated stink bug (Halyomorpha halys). Stink bugs get their name from the foul odour they release when threatened. Nymphs and adults prefer field corn and soybean, but infestations have been reported on rape, pea, sunflower and cereals in the USA. They have also been known to attack tree fruits, berries, vegetables and many ornamental trees and shrubs. They are not known to be established in the Prairies, but have been found in the BC Southern Interior, Ontario and Quebec. Feeding causes damage to seeds and seed pods, reducing yield.
Brown marmorated stink bug – adult (CC-BY 2.0 Katja Schulz)
This is the last Weekly Update of the 2016 growing season! Many thanks to everyone who helped prepare the various sections and insect pest updates for the past 17 weeks! Thanks to those of you who monitor and good luck with harvest! A downloadable PDF version of the complete Weekly Update for Week 17 (August 24, 2016) can be accessed here.
Questions or problems accessing the contents of this Weekly Update? Please e-mail either Dr. Owen Olfert or Jennifer Otani. Past “Weekly Updates” are very kindly archived to the Western Forum website by webmaster, Dr. Kelly Turkington.
Pre-Harvest Interval (PHI) -Reminder – Growers with late-season insect pest problems will need to remember to factor in the PHI which is the minimum number of days between a pesticide application and swathing or straight combining of a crop. The PHI recommends sufficient time for a pesticide to break down and a PHI-value is both crop- and pesticide-specific. Adhering to the PHI is important for a number of health-related reasons but also because Canada’s export customers strictly regulate and test for the presence of trace residues of pesticides. An excellent summary of PHI for various pesticides in their various crops was posted by Saskatchewan Agriculture this week within their Crop Production News.
In 2013, the Canola Council of Canada created and circulated their “Spray to Swath Interval Calculator” which was intended to help canola growers accurately estimate their PHI. Other PHI are described in your provincial crop protection guides and remember that specific crop x pesticide combinations will mean different PHIs. More information about PHI and Maximum Residue Limits (MRL) is available on the Canola Council of Canada’s website.
Dr. Meghan Vankosky started her position as a research scientist with Agriculture and Agri-Food Canada at the Saskatoon Research and Development Centre on July 18, 2016. Most recently, Meghan worked as a postdoctoral scholar at the University of California, Riverside. Her work there focused on establishing a release program for a parasitoid used for biological control of the Asian citrus psyllid in southern California, and on studying the competitive interactions of that parasitoid with another primary parasitoid of the pest. In the past, Meghan studied the behavior and life history of an omnivore used for biological control at the University of Windsor in Ontario (Ph.D., 2010-2015), and integrated pest management strategies and biological control of the pea leaf weevil at the University of Alberta (M.Sc., 2008-2010).
As a field crop entomologist with AAFC, Meghan hopes to develop a strong IPM-based research program that focuses on understanding insect pests and developing sustainable management programs that will benefit both producers and the environment. She currently plans to investigate the impact of the pea leaf weevil and assess management options for this pest in Saskatchewan. She will also be involved with a project studying the life history and impact of the swede midge in canola crops in the Prairies.
Dr. Boyd Mori – (Research Scientist – Entomology) Boyd completed his PhD in 2014 at the University of Alberta on pheromone monitoring and management of the red clover casebearer (Coleophora deauratella) moth in the Peace River region of Alberta. He then undertook a Postdoctoral Fellowship at the Swedish University of Agricultural Sciences (Alnarp, Sweden) where he researched the chemical ecology of the highly invasive spotted wing fruit fly (Drosophila suzukii) with a focus on alternative pest management strategies. Boyd joined AAFC-Saskatoon in April 2016. Boyd’s primary project will be on the ecology of swede midge-host plant interactions, where he aims to identify host plant resistance mechanisms against the swede midge, a potentially significant pest of canola. He is a strong proponent of integrated pest management and has a robust background in insect behaviour and physiology which he uses to develop monitoring and management tools for insect pests.
As of March 2020, Dr. Mori took an Assistant Professor position with the University of Alberta. He can be reached at bmori@ualberta.ca
Dr. Tyler Wist spent his early insect years killing mosquitoes before studying pollinators in Echinacea crops for his M.Sc. with Dr. Art Davis at the University of Saskatchewan. A Ph.D. from the University of Alberta with Dr. Maya Evenden taught him the unseen world of insect chemical ecology, and invasion dynamics and the parasitoid complex of a recently introduced lepidopteran pest, the ash leaf coneroller. Drs. Chrystel Olivier and Owen Olfert brought him in on an NSERC Visiting Fellowship on the cereal aphid project and then had him chasing leafhoppers in cereal and canola crops. Tyler is the current President of the Entomological Society of Saskatchewan and has begun a research scientist position at Agriculture and Agri-Food Canada’s Research and Development Centre in Saskatoon as a Field Crop Entomologist on January 25th 2016.
Tyler is working on developing a dynamic action threshold for cereal aphids that incorporates the predatory pressure of natural enemies, determining the economic threshold and effect of landscapes on flea beetles in newer, hybrid canola varieties, and tracking aster leafhopper populations and aster yellows infection in canola and cereal crops. He is also investigating new integrated pest management tools for wheat midge and chasing Lygus bugs in canola and aphids in pulse crops.
The Canola Council of Canada created a guide to help growers estimate swathing time in canola. A screen shot of the downloadable Canola Swathing Guide has been included below for reference.
Upcoming Meetings and Conferences – The following agricultural insect pest-related meetings and conferences are scheduled for this year:
• September 25-30, 2016: The 25th International Congress of Entomology / Entomological Society of America / Entomological Society of Canada AGMs will be held at Orlando FL. More information is available at: http://ice2016orlando.org/
• October 2016: The annual meeting of the Entomological Society of Alberta will be held at Calgary AB. Details will be posted soon at: http://www.entsocalberta.ca/esa.htm
• October 19-21, 2016: The Western Forum on Pest Management 2016 meets at Saskatoon SK. Check http://www.westernforum.org/WFPM%20Annual%20Meeting%20Annoucement.htm for more information and check both the Western Committee on Crop Pests and Western Committee on Plant Diseases webpages for updated agendas.
• October 21, 2016: The Canadian Forum for Biological Control will meet immediately following the Western Forum on Pest Management at Saskatoon SK the afternoon of October 21, 2016.
• TBA: Refer to the Entomological Society of Saskatchewan’s website for upcoming events. Information will be posted at: http://www.entsocsask.ca/events.html
• November 22-24, 2016: The Canadian Weed Science Society meets in Moncton NB and more information is available at http://weedscience.ca/meeting-home/
• January 9-11, 2017: CropSphere Agricultural Conference will be held at Saskatoon SK. More information is available at: http://www.cropsphere.com/
• January 17-19, 2017: The Manitoba Ag Days show will be held at Brandon MB. More information will be available at: https://www.agdays.com/
The Canadian Grain Commission is ready and willing to grade grain samples harvested in 2016. Samples are accepted up to November but send samples as soon a harvest is complete. This is a FREE opportunity for growers to gain unofficial insight into the quality of their grain and to obtain valuable dockage information and details associated with damage or quality issues. The data collected also helps Canada market its grain to the world! More information on the Harvest Sample Program is available at the Canadian Grain Commission’s website where growers can register online to receive a kit to submit their grain.
In exchange for your samples, the CGC assesses and provides the following unofficial results FOR FREE:
dockage assessment on canola
unofficial grade
protein content on barley, beans, chick peas, lentils, oats, peas and wheat
oil, protein and chlorophyll content for canola
oil and protein content and iodine value for flaxseed
oil and protein for mustard seed and soybeans
Many producers find having both grade and quality information on their samples before delivering their grain to be helpful.
Dr. Haley Catton joined AAFC-Lethbridge as a Research Scientist in Cereal Crop Entomology in April 2016. With a diverse background in studying trees, weeds, native plants, insects, and mammals, Haley specializes in population biology, insect-plant interactions, biological control, field experimentation and analysis of large data sets. Originally from Winnipeg, Haley earned a B.Sc. (Agriculture) and M.Sc. (Plant Science) from the University of Manitoba, a Ph.D. (Insect-Plant Interactions) from the University of British Columbia Okanagan, and conducted postdoctoral research at the University of Lethbridge. Her research program at AAFC will draw from all of these experiences to focus on pest and beneficial insects in cereal crops on the prairies. Her target pests range from established problems like wheat stem sawfly and wireworm to emerging pests such as the invasive cereal leaf beetle.
Haley wants to connect with producers and hear about your priorities for research. Follow her on Twitter at @haleycatton or reach her at haley.catton@agr.gc.ca or 403.317.3404. Fair warning: Haley is a diehard Blue Bombers fan… Saskatchewan Roughriders fans beware.
West Nile Virus Risk – The regions most advanced in degree-day accumulations for Culex tarsalis, the vector for West Nile Virus, are shown in the map below. As of August 21, 2016, areas highlighted in yellow, orange, or red on the map below have accumulated sufficient heat for C. tarsalis to fly so wear your DEET to stay protected!
The Canadian Wildlife Health Cooperative compiles and posts information related to their disease surveillance for West Nile Virus. As of August 22, 2016, 36 birds were submitted for testing and two have tested positive for West Nile virus in Ontario.
The USDA publishes a Crop Production Report (Posted August 12, 2016) and a Crop Progress Report (posted August 22, 2016) which includes harvest and condition ratings for winter wheat, spring wheat, oat, barley, plus range and pasture conditions.
The USDA also produces a World Agricultural Production Report (August 2016) which estimates production across the globe for corn, cotton, rapeseed, and wheat but also includes tabular data for other grains.
This week’s Insect of the Week is the corn earworm (Helicoverpa zea), an annual migrant from Mexico and southern USA. According to Wikipedia, the corn earworm is the second most important economic insect pest in North America. See information from the new Field Crop and Forage Pests and their Natural Enemies in Western Canada – Identification and Management Field Guide for identification, life cycle and control options (download links for field guide available on the Insect of the Week page).
