Wind trajectories

Agriculture and Agri-Food Canada (AAFC) and Environment and Climate Change Canada (ECCC) have been working together to study the potential of trajectories for monitoring insect movements since the late 1990s.

The entire list of 2020 Wind Trajectory Reports is available here.

→ Read the WEEKLY Wind Trajectory Report for Wk04 (released May 18, 2020).

→ Read the DAILY Wind Trjectory Reports for Wk04 (released May 20 and May 21).

Weekly Update

The phenology models used to predict insect staging and associated risk to field crops on the Prairies is a complex system with multiple moving parts.  Last week, phenology model output and map development was not available owing to the detection of an error in one of the underlying datasets required to run the models.  We are pleased to report that the error has been resolved for this week.

At this moment, segments of earlier 2020 Weekly Updates have been pulled back.  The phenology models for Wk01 and Wk02 will be reposted once we have had opportunity to re-run the models with the correct datasets and re-map the model outputs.  Stay tuned and thank you for your patience!

Access information to support your in-field insect monitoring efforts in the complete Weekly Update either as a series of Posts for Week 4 OR  a downloadable PDF.

Stay Safe!

Questions or problems accessing the contents of this Weekly Update?  Please e-mail Dr. Meghan Vankosky or Jennifer Otani.  Past “Weekly Updates” can be accessed on our Weekly Update page.

Chickpea and Lentil Pests / Feature (honorary) ‘Entomologist’ Erl Svendsen

This week’s Insect of the Week feature crops are chickpea and lentil and Erl Svendsen is our feature ‘entomologist.’

Lentil Plant
cc by 3.0 Christiaan Kooyman

Lentils (green, red, black beluga, French green, Spanish brown) and chickpeas (desi, kabuli) are important Prairie crops introduced to the region in the 1970s and 1980s. These crops are good options to include in your rotation. Except for a few acres in Ontario, lentils and chickpeas are grown in Alberta and Saskatchewan, with Saskatchewan accounting for 90% of production. In 2019, lentils were grown on 1.5 million hectares (3.8 million acres) and yielded 2.2 metric tonnes (2.4 US tons). Chickpeas were grown on 160,000 hectares (390,000 acres) and yielded 250,000 metric tonnes (280,000 US tons). Over 70% of production is exported.

There are a number of pests that attack these crops, many are common to both crops. Monitoring and scouting protocols are found in the Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and Management and the Cutworm Pests of Crops on the Canadian Prairies: Identification and Management Field Guide. More detailed protocols exist for some of the pests.

Lentil Pests
  • Cutworms
  • Grasshoppers
  • Lygus bugs
  • Pea aphid
  • Wireworms
Chickpea Pests
  • Alfalfa loopers
  • Cutworms
  • Grasshoppers
  • Wireworms
Pea aphid
cc by 2.0 Mike Dolinski

Entomologist of the Week: Erl Svendsen

Name: Erl Svendsen
Affiliation: Agriculture and Agri-Food Canada
Contact Information: erl.svendsen@canada.ca, @ErlSv

How do you contribute in insect monitoring or surveillance on the Prairies? 

Full disclosure: I am not an entomologist by any stretch of the imagination. But much of my recent work was been to support the communications efforts by the real entomologists of the network. I was the co-lead for the Cereal Aphid Manager app, and have edited done the layout and design of the recent insect field guides. More recently, I’ve been working with a great team to develop the new PPMN website, to be launched soon. I am also responsible for putting out the Insect of the Week post.

In your opinion, what is the most interesting field crop pest on the Prairies?

Considering I knew very little about the life histories of many of the pest and their natural enemies when I started working the entomologists 7 years ago, it’s hard to pick a favourite. Back to the wall, I would have to say the lowly cutworm. Who knew there were so many pest species with very different behaviours. Which makes them a challenging group to manage.

What is your favourite beneficial insect? 

I’ve always had a special place in my heart for ladybird beetle. Not only are they beautiful and brightly coloured (orange with black spots), they are voracious, gobbling down hundreds (if not thousands) of aphids and other soft-bodied pests in their short lifespan. And unlike many other natural enemies, both the adult and the larva are mighty hunters.

Tell us about an important project you are working on right now. 

I am working with Drs. Haley Catton, Wim van Herk and Julien Saguez on a new Wireworm Field Guide for the Prairies. It summaries all the wireworm research conducted on the Prairies since the 1910s as well as pulling in relevant research from other regions. And of course there will be high quality images throughout. Look for an announcement and download links later this summer.

What tools, platforms, etc. do you use to communicate with your stakeholders? 

In addition to the PPMN blog (new website to be launched soon), I work with the entomologists to develop manuals and factsheets. I use Twitter (@ErlSv) and have a booths at several extension events throughout the year to promote the PPMN and other AAFC research programs.

Weather synopsis

Weather synopsis – Temperatures (30 day average) continue to be warmest in southern AB and western SK (Fig. 1). Across the prairies, the monthly average temperature was slightly cooler than normal.  

Figure 1.  Average temperatures across the Canadian prairies (°C) from March 31-April 30, 2019.

Rainfall (30 day accumulation) amounts have been well below average for most of the prairies (Figs. 2 and 3). Rainfall amounts (30 day) across southern SK are normal to above normal. 

Figure 2.  Accumulated 30 day cumulative rainfall (mm) across the Canadian prairies from March 31-April 30, 2019.
Figure 3.  Percent of average precipitation across the Canadian prairies from March 31-April 30, 2019.
Image has not been reproduced in affiliation with, or with the endorsement of the 
Government of Canada and was retrieved (01May2019).  
Access the full map at http://www.agr.gc.ca/DW-GS/current-actuelles.jspx?lang=eng&jsEnabled=true

On March 27 and 28 significant snowfall amounts were reported for a number of locations across AB and southern SK (Table 1; Fig. 4). This has resulted in improved soil moisture amounts for the southern  SK (Fig. 5).

Figure 4.  Observed 7-day cumulative rain (mm) across the Canadian prairies (April 23-30, 2019).
Figure 5.  Modeled soil moisture (%) across the Canadian prairies (as of April 30, 2019).

Wind trajectories

Agriculture and Agri-Food Canada (AAFC) and Environment and Climate Change Canada (ECCC) have been working together to study the potential of trajectories for monitoring insect movements since the late 1990s. Trajectory models are used to deliver an early-warning system for the origin and destination of migratory invasive species, such as diamondback moth.  In addition, plant pathologists have shown that trajectories can assist with the prediction of plant disease infestations and are also beginning to utilize these same data. We receive two types of model output from ECCC: reverse trajectories and forward trajectories.

‘Reverse trajectories’ (RT) refer to air currents that are tracked back in time from specified Canadian locations over a five-day period prior to their arrival date.  Of particular interest are those trajectories that, prior to their arrival in Canada, originated over northwestern and southern USA and Mexico, anywhere diamondback moth populations overwinter and adults are actively migrating.  If diamondback adults are present in the air currents that originate from these southern locations, the moths may be deposited on the Prairies at sites along the trajectory, depending on the local weather conditions at the time that the trajectories pass over our area (e.g. rain showers, etc.). Reverse trajectories are the best available estimate of the ”true” 3D wind fields at a specific point. They are based on observations, satellite and radiosonde data.

‘Forward trajectories’ (FT) have a similar purpose; however, the modelling process begins at sites in USA & Mexico. The model output predicts the pathway of a trajectory. Again, of interest to us are the winds that eventually end up passing over the Prairies.

Ross Weiss (AAFC), Meghan Vankosky (AAFC) and Serge Trudel (ECCC)

DATE: APRIL 30, 2019

1. Reverse trajectories (RT)

a.  Pacific Northwest (PNW) – For the period of April 24-30 there have been 18 RTs (originating over ID, OR and WA) that have crossed over prairie locations.  By comparison, for the period of April  17-23 there were 51 RT’s. The majority PNW RTs have been reported to pass over southern AB.  Since March 23rd  Lethbridge AB has reported the highest number of PNW RTs (n=22), Beiseker AB  (n=15) and Olds AB (n=31).

Figure 1.  Daily total number of reverse trajectories (RTs) originating over Idaho, Oregon, and Washington that have crossed the Canadian prairies as of April 30, 2019.
Figure 2.  Total number of dates with PNW reverse trajectories originating over Idaho, Oregon, and Washington that have crossed the Canadian prairies (since March 23, 2019).
Figure 3.  List of PNW (Idaho, Oregon, and Washington) reverse trajectories that have crossed the prairies (since March 23, 2019).

b.  Mexico and SW USA (TX, CA) – No trajectories, originating over Mexico or southwest USA have crossed the prairies for the period of April 24-30, 2019. Since March 23, 2019 there have been 5 reverse trajectories that originated over Mexico, CA and TX. All five occurred on April 7.

c.  Texas and Oklahoma – No trajectories, originating over TX or OK have crossed the prairies for the period of April 24-30, 2019.  Since March 23, 2019 there have been 18 reverse trajectories that have originated over OK and TX. Most of these trajectories have crossed eastern SK and MB.

2.  Forward trajectories (FT) – 

The following table reports the origin of forward trajectories predicted to cross the prairies over the next five days (Note: ‘InitialDate’ refers to when the forward trajectory crossed the source location. Trajectories are predicted to cross prairie locations within five days of the initial date).  

In a continuing effort to produce timely information, wind trajectory reports will be available both DAILY and WEEKLY:

Weather forecasts (7 day):

Cutworms

Cutworms (Noctuidae) – A field guide is now available to help growers scout and manage Cutworms!  Cutworm Pest of Crops is available for free in either English or French and is posted on the Cutworm Field Guide page!  

Several species of cutworms can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  Cutworm biology, species information, plus monitoring recommendations are available in the Prairie Pest Monitoring Network’s Cutworm Monitoring Protocol.  Also refer to Manitoba Agriculture cutworm fact sheet which includes action and economic thresholds for cutworms in several crops. 

Scout fields that are “slow” to emerge, are missing rows, include wilting or yellowing plants, have bare patches, or appear highly attractive to birds – these are areas warranting a closer look.  Plan to follow-up by walking these areas later in the day when some cutworm species move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of a symptomatic plant or the adjacent healthy plant.  If the plant is well-established, check within the crown in addition to the adjacent soil.  The culprits could be wireworms or cutworms.  

For Albertans….. If you find cutworms, please consider using the Alberta Pest Surveillance Network’s “2019 Cutworm Reporting Tool” then view the live 2019 cutworm map which is updated daily.

Flea beetles

Flea Beetles (Chrysomelidae: Phyllotreta species) – Be on the lookout for flea beetle damage resulting from feeding on canola cotyledons but also on the stem.  Two species, Phyllotreta striolata and P. cruciferae, will feed on all cruciferous plants but they can cause economic levels of damage in canola during the seedling stages.

Remember, the Action Threshold for flea beetles on canola is 25% of cotyledon leaf area consumed.  Watch for shot-hole feeding in seedling canola but also watch the growing point and stems of seedlings which are particularly vulnerable to flea beetle feeding.

Estimating flea beetle feeding damage can be challenging.  Using a visual guide to estimate damage can be helpful.  Canola Watch circulated this article but also use the two images (copied below for reference) produced by Dr. J. Soroka (AAFC-Saskatoon)  – take it scouting!

Figure 1. Canola cotyledons with various percentages of leaf area consume owing to 
flea beetle feeding damage (Photo: Soroka & Underwood, AAFC-Saskatoon).
Figure 2.  Percent leaf area consumed by flea beetles feeding on canola seedlings 
(Photo: Soroka & Underwood, AAFC-Saskatoon).

Refer to the flea beetle page from the “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.

Alfalfa weevil

Alfalfa Weevil (Hypera postica) – Degree-day maps of base 9°C are produced using the Harcourt/North Dakota models (Soroka et al. 2015).  Models predicting the development of Alfalfa weevil (Hypera postica) across the prairies are updated weekly to help growers time their in-field scouting for second-instar larvae. 

The AAW model runs indicate that oviposition has begun in fields near Swift Current SK (Fig. 1). Compared to last week, oviposition rates are predicted to have increased.

Figure 1.  Predicted AAW adults near Swift Current SK as of April 30, 2019.

The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer”.  The green larva featuring a dorsal, white line down the length of its body has a dark brown head capsule and will grow to 9mm long.  

Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (Philip et al. 2015).  The guide is available in both a free English-enhanced or French-enhanced version.

Pea leaf weevil

Pea Leaf Weevil (Sitona lineatus– The PLW model was run for Red Deer AB (Fig. 1) and Saskatoon SK (Fig. 2). The output suggests that PLW are beginning to become active and will begin to fly on warmer days (Figs. 1 and 2). 

Figure 1.  Predicted overwintered PLW adults near Red Deer AB as of April 30, 2019. 
Figure 2.  Predicted overwintered PLW adults near Saskatoon SK as of April 30, 2019. 

Pea leaf weevils emerge in the spring primarily by flying (at temperatures above 17ºC) or they may walk short distances. Pea leaf weevil movement into peas and faba beans is achieved primarily through flight.  Adults are slender, greyish-brown measuring approximately 5 mm in length (Fig. 3, Left).  

The 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).

Adults will feed upon the leaf margins and growing points of legume seedlings (alfalfa, clover, dry beans, faba beans, peas) and produce a characteristic, scalloped (notched) edge.  Females lay 1000 to 1500 eggs in the soil either near or on developing pea or faba bean plants from May to June.

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.

Also refer to the pea leaf weevil page within the “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.  A review of this insect was published in 2011 in Prairie Soils and Crops by Carcamo and Vankosky.

Cereal leaf beetle

Cereal leaf beetle (Oulema melanopus) – Model output indicates that CLB adults have begun to oviposit eggs near Lethbridge AB (Fig. 1). 

Figure 1.  Predicted CLB adults near Lethbridge AB as of April 30, 2019.

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Fig. 2). 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 shelter belts, deciduous and conifer forests. They emerge in the spring once temperature reaches 10-15 ºC and are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 2. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).

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 (Fig. 3).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 3.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf (Photo: M. Dolinski).

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.

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the new “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide”.

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.

Scouting Charts – Canola and Flax

Field scouting is critical – it enables the identification of potential risks to crops. Accurate identification of insect pests PLUS the application of established monitoring methods will enable growers to make informed pest management decisions.

We offer TWO generalized insect pest scouting charts to aid in-field scouting on the Canadian prairies:

1. CANOLA INSECT SCOUTING CHART

2018_ScoutingChart_Canola

2. FLAX INSECT SCOUTING CHART

2018_ScoutingChart_Flax

These charts feature hyperlinks directing growers to downloadable PDF pages within the “Field crop and forage pests and their natural enemies in western Canada: Identification and management field guide“.

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 outbreaking insect pest species.

Good luck with your scouting!

Ticks and Lyme Disease

Remember to watch for ticks at this time of year!  Blacklegged (deer) ticks are important because they can carry Lyme Disease.  Continued surveillance activities conducted by Health Canada and the provinces remain important and you can help by identifying / removing / submitting your ticks!

Follow the links to learn more and to submit ticks if you live in British ColumbiaAlbertaSaskatchewanManitobaOntario, or Quebec.

Figure 1. Screenshot of Health Canada’s map of Lyme disease endemic and risk areas in Canada as of 2016 (retrieved 24Apr2019).

Previous Posts

Click to review any of these earlier 2019 Posts:

2019 Risk and forecast maps – Week 2

Wind trajectories – Weeks 1-3

Weekly Update

Greetings!

What an incredible mix of weather this week – flooding, dangerously dry, blizzards that shut highways and airports!  Even so, seeding is underway in parts of the prairies!  

Access the complete Weekly Update either as a series of Posts for Week 04 (May 2, 2019) OR a downloadable PDF version.

Questions or problems accessing the contents of this Weekly Update?  Please e-mail either Dr. Meghan Vankosky or Jennifer Otani.  Past “Weekly Updates” can be accessed on our Weekly Update page.

Subscribe to the Blog by following these easy steps!

Weekly Update

Greetings!

Access the complete Weekly Update either as a series of Posts for Week 04 (May 31, 2018) OR downloadable PDF version.  Also review the “Insect of the Week” for Week 4!



Questions or problems accessing the contents of this Weekly Update?  Please e-mail either Dr. Meghan Vankosky or Jennifer Otani.  Past “Weekly Updates” can be accessed on our Weekly Update page.

Subscribe to the Blog by following these three steps!

Wind trajectories

Background:  Agriculture and Agri-Food Canada (AAFC) and Environment and Climate Change Canada (ECCC) have been working together to study the potential of trajectories to deliver an early-warning system for the origin and destination of migratory invasive agricultural pests.


We receive two types of model output from ECCC: reverse trajectories (RT) and forward trajectories (FT): 

(i) ‘Reverse trajectories’ (RT) refer to air currents that are tracked back in time from specified Canadian locations over a five-day period prior to their arrival date. 

(ii) ‘Forward trajectories’ (FT) have a similar purpose; however, the modelling process begins at sites in USA and Mexico. The model output predicts the pathway of a trajectory. Again, of interest are the winds that eventually end up passing over the Prairies. 


Current Data


Since May 21, 2018, the number of incoming trajectories (RTs) crossing the prairies has increased, particularly from California, Texas and Mexico (Fig. 1). The increased number of reverse trajectories could result in increased introductions of insects into the prairies.

Figure 1.  Daily total number of reverse trajectories, originating over the Pacific Northwest AND
Southwest of the USA, that have entered the Canadian prairies (May 1-28, 2018).





Weather forecasts (7 day):

Flea beetles

Flea Beetles (Chrysomelidae: Phyllotreta species) – The Insect of the Week features flea beetles!


Be on the lookout for flea beetle damage resulting from feeding on canola cotyledons but also on the stem.  Two species, Phyllotreta striolata and P. cruciferae, will feed on all cruciferous plants but they can cause economic levels of damage in canola during the seedling stages.


Remember, the Action Threshold for flea beetles on canola is 25% of cotyledon leaf area consumed.  Watch for shot-hole feeding in seedling canola but also watch the growing point and stems of seedlings which are particularly vulnerable to flea beetle feeding.


Estimating flea beetle feeding damage can be challenging.  Using a visual guide to estimate damage can be helpful.  Canola Watch circulated this article but also use the two images (copied below for reference) produced by Dr. J. Soroka (AAFC-Saskatoon)  – take it scouting!

Figure 1. Canola cotyledons with various percentages of leaf area consume owing to 
flea beetle feeding damage (Photo: Soroka & Underwood, AAFC-Saskatoon).

Figure 2.  Percent leaf area consumed by flea beetles feeding on canola seedlings 
(Photo: Soroka & Underwood, AAFC-Saskatoon).


Refer to the flea beetle page from the “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.

Weather synopsis

Weather synopsis – Weather conditions continue to be warmer and dryer than average across most of the prairies. This past week, (May 22 – 29, 2018) the average temperature was approximately 4 °C warmer than long term average (Fig. 1).  The warmest weekly temperatures occurred across MB. 

Figure 1. Weekly (May 22 – 29, 2018) average temperature (°C) . 

The 30-day average temperature (April 29 – May 29) was approximately 2 °C warmer than long term average (Fig. 2).  

Figure 2.  The 30-day (April 29 – May 29, 2018) average temperature (°C).





Weekly precipitation was below average and 30-day total rainfall was approximately 50% less than average (Figs. 3 and 4). 

Figure 3.  Weekly (May 22 – 29, 2018) cumulative precipitation (mm).


Figure 4.  The 30-day (April 29 – May 29, 2018) cumulative precipitation (mm).



Accumulated precipitation for the growing season (April 01-May 30, 2018) is shown below.

The map below reflects the Highest Temperatures occurring over the past 7 days (May 24-30, 2018) across the prairies. 


The map below reflects the Lowest Temperatures occurring over the past 7 days (May 24-30, 2018) across the prairies – it got a bit chilly for our newly seeded crops! 


The growing degree day map (GDD) (Base 10ºC, March 1 – May 30, 2018) is below:


The growing degree day map (GDD) (Base 5ºCMarch 1 – May 30, 2018) 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.

Cutworms

Cutworms (Noctuidae) – A field guide is available to help growers scout and manage Cutworms!  Cutworm Pest of Crops is available for free in either English or French and is posted on the Cutworm Field Guide page!  Also be sure to check the Insect of the Week through May – it highlights cutworms.  

Several species of cutworms  can be present in fields.  They range in colour from shiny,  opaque, to tan, to brownish-red with chevron patterning.  Cutworm biology, species information, plus monitoring recommendations are available in the Prairie Pest Monitoring Network’s Cutworm Monitoring Protocol.  Also refer to Manitoba Agriculture cutworm fact sheet which includes action and economic thresholds for cutworms in several crops. 

Scout fields that are “slow” to emerge, are missing rows, include wilting or yellowing plants, have bare patches, or appear highly attractive to birds – these are areas warranting a closer look.  Plan to follow-up by walking these areas later in the day when some cutworm species move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of a symptomatic plant or the adjacent healthy plant.  If the plant is well-established, check within the crown in addition to the adjacent soil.  The culprits could be wireworms or cutworms.  

The following page extracted from the new “Cutworm Pests of Crops on the Canadian Prairies” (Floate 2017; Page 5) shows the seasonal occurrence of lifecycle stages for different species of cutworms.  To aid scouting, the seasonal chart outlines what time of year larvae of different pest species are present (i.e., when to scout) but it also describes larval feeding habit (i.e., where to look for them relative to the plant host). 

 


For Albertans….. If you find cutworms, please consider using the Alberta Pest Surveillance Network’s “2018 Cutworm Reporting Tool”.  Once data entry occurs, growers can view the live 2018 cutworm map which is updated daily (see below for screenshot of map retrieved June 5, 2018).

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.

Pea leaf weevil

Pea Leaf Weevil (Sitona lineatus– The PLW model predicts that oviposition is occurring across southern and central regions of the prairies (example Swift Current – Fig. 1). 

Figure 1.  Predicted pea leaf weevil phenology at Swift Current SK.
Values are based on model simulations (April 1-May 28, 2018 and projected to July 1, 2018).



Pea leaf weevils emerge in the spring primarily by flying (at temperatures above 17ºC) or they may walk short distances. Pea leaf weevil movement into peas and faba beans is achieved primarily through flight.  Adults are slender, greyish-brown measuring approximately 5 mm in length (Fig. 2, Left).  

The 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 2.  Comparison images and descriptions of four Sitona species adults including pea leaf weevil (Left).


Adults will feed upon the leaf margins and growing points of legume seedlings (alfalfa, clover, dry beans, faba beans, peas) and produce a characteristic, scalloped (notched) edge.  Females lay 1000 to 1500 eggs in the soil either near or on developing pea or faba bean plants from May to June.


Reminder – The 2017 risk map for pea leaf weevils was released in March 2018.  The map is based on the number of feeding notches observed in peas (Fig. 3).  

Figure 3. Estimates of pea leaf weevil (S. lineatus) densities based on feeding notches observed in
peas grown in Alberta and Saskatchewan in 2017.

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.

Also refer to the pea leaf weevil page within the “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.  A review of this insect was published in 2011 in Prairie Soils and Crops by Carcamo and Vankosky.

Cereal leaf beetle

Cereal leaf beetle (Oulema melanopus) – Model output indicates that CLB are primarily in the larval stage (example Lethbridge – Fig. 1). 
Figure 1. Predicted cereal leaf beetle phenology at Lethbridge AB. 
Values are based on model simulations (April 1-May 28, 2018 and projected to June 21, 2018).

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Fig. 2). 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 shelter belts, deciduous and conifer forests. They emerge in the spring once temperature reaches 10-15 ºC and are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 2. Adult Oulema melanopus measure 4.4-5.5 mm long (Photo: M. Dolinski).


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 (Fig. 3).  When the larva completes its growth, it drops to the ground and pupates in the soil. 


Figure 3.  Larval stage of Oulema melanopus with characteristic feeding 
damage visible on leaf (Photo: M. Dolinski).

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.

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the new “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide”.

Alfalfa weevil

Alfalfa Weevil (Hypera postica) – The AAW model runs for Swift Current SK indicate that oviposition is well underway in southern Saskatchewan (Fig. 1).  Larvae should be primarily second and third instars. Fourth instar larvae may be occurring as well. 

Figure 1.  Predicted alfalfa weevil phenology at Swift Current SK. 
Values are based on model simulations (April 1-May 28, 2018 and projected to June 21, 2018).



Degree-day maps of base 9°C are produced using the Harcourt/North Dakota models (Soroka et al. 2015).  Models predicting the development of Alfalfa weevil (Hypera postica) across the prairies are updated weekly to help growers time their in-field scouting for second-instar larvae. Compare the following predicted development stages and degree-day values from Soroka (2015) to the map below (Fig. 2).  

Figure 2.  Predicted development of alfalfa weevil as of May 30, 2018.

The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer”.  The green larva featuring a dorsal, white line down the length of its body has a dark brown head capsule and will grow to 9mm long.  



Use the photo below as a visual reference to identify alfalfa weevil larvae.  Note the white dorsal line, the tapered shape of the abdomen and the dark head capsule.



Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).  Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (Philip et al. 2015).  The guide is available in both a free English-enhanced or French-enhanced version.


New Predictive Model Update Page

Updated phenology models for insect pests on the Canadian prairies will be posted to our new Predictive Model Update page during the growing season, as they become available.  This information is intended to supplement the Weekly Updates while providing the most current information to further support in-field scouting.

Whenever items are posted to this page, @vanbugsky will be Tweeting and using #PPMNblog to help users access this most up-to-date information.

This week, an updated table of predicted emergence dates for bertha armyworm was posted for across the Canadian prairies (May 30, 2018).  Those in charge of coordinating deployment of pheromone traps will need to pay particular attention to these dates.

Predicted bertha armyworm development

Bertha armyworm (Lepidoptera: Mamestra configurata– The BAW model is predicting that pupae are developing rapidly in the soil and that development is well ahead of average (Fig. 1).  Development is expected to be 5 – 6 days faster than average. 

Figure 1.  Predicted bertha armyworm pupal development (as of May 30, 2018).

Pupal development is approximately 72% (long term average is 47%). Model output predicts that emergence may begin as early as June 6, 2018 (Table 1).


Table 1.  Projected dates for bertha armyworm adult emergence as of May 28, 2018 and projecting to June 30, 2018.

Reminder – Review the 2017 bertha armyworm distribution map for the Canadian prairies which reports cumulative pheromone trap counts intercepting male moths during the 2017 growing season.



Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of ManitobaSaskatchewanAlberta and the Prairie Pest Monitoring Network.  Also refer to the bertha armyworm 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.

Cabbage seedpod weevil

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.




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.


Damage: 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.


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

Ticks and Lyme Disease

As the spring weather improves and people are active outdoors, remember to watch for ticks.  Blacklegged (deer) ticks are important because they can carry Lyme Disease.  Continued surveillance activities conducted by Health Canada and the provinces remain important and you can help by identifying / removing / submitting your ticks!

Follow the links to learn more and to submit ticks if you live in British ColumbiaAlbertaSaskatchewanManitobaOntario, or Quebec.
Figure 1. Screenshot of Health Canada’s map of Lyme disease endemic and risk areas in Canada (retrieved 24May2018).

PMRA Pesticide Label Mobile App

Remember – Health Canada’s Pest Management Regulatory Agency launched a mobile app to access pesticide labels registered for use in Canada. The App helps homeowners, farmers, industry, provincial and federal organizations access details for pest control products from a smartphone or tablet (Fig. 1). 

Users can save searches, download product labels to their ‘Favourites’ which can even be accessed while offline. ‘Favourites’ will also auto-update when accessed online. Pesticide labels can be searched based by product name or active ingredient (e.g., to review detailed explanations on proper product use and necessary precautions).

Users can download the app on their mobile device.

If you have any questions, please contact the PMRA’s Information Service.

Figure 1. Screenshot view of Pesticide Label download page (retrieved 24May2018).


Provincial Insect Pest Reports

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 2018 will be posted soon. Review the most recent updated (May 30, 2018) prepared by John Gavloski and Holly Derksen. The insect update notes flea beetles in canola and cutworms.

Saskatchewan‘s Crop Production News for 2018 is now posted. Access Report #1 posted May 31, 2018, and be sure to review the articles posted for flea beetles and pea leaf weevils to prepare for field scouting. Also know that Saskatchewan growers can review diamondback moth pheromone trap counts in the upper right of the diamondback moth page.

Access Alberta Agriculture and Forestry’s Call of the Land for insect pest updates from Scott Meers. The most recent Call of the Land (posted on May 31, 2018) and highlights scouting for flea beetles with the warmer weather, glassy cutworms in perennial forages crops and more recently in the irrigated acres to the south of the province (please report using online cutworm reporting tool), relatively low numbers of diamondback moth on pheromone traps in the 4th week of monitoring and relatively low pea leaf weevil numbers so far based on field assessments completed in southern Alberta to date.

Crop reports

Crop reports are produced by:
• Manitoba Agriculture, Rural Development (May 28, 2018)
• Saskatchewan Agriculture Crop Report (May 22-28, 2018)
• Alberta Agriculture and Forestry Crop Report (May 22, 2018)

The following crop reports are also available:
• The United States Department of Agriculture (USDA) produces a Crop Progress Report (view the May 29, 2018 edition).

• The USDA’s Weekly Weather and Crop Bulletin (view the May 30, 2018 edition).

Monarch migration

We again track the migration of the Monarch butterflies as they move north by checking the 2018 Monarch Migration MapA screen shot of the map has been placed below as an example (retrieved 29May2018) but follow the hyperlink to check the interactive map! 



Visit the Journey North website to learn more about migration events in North America and visit their monarch butterfly website for more information related to this fascinating insect.  

Previous Posts

The following is a list of 2018 Posts – click to review:

Cereal aphid manager (CAM) – Week 2
Crop protection guides – Week 2


Scouting charts (canola and flax) – Week 3


Weather radar – Week 3

Insect of the Week – Flea Beetles

This week’s Insect of the Week is the Flea Beetle (Phyllotreta species). This group of beetles is typically oval and 2-3 mm long.  In canola, the most common flea beetles are either bluish black (crucifer flea beetle or Phyllotreta cruciferae) or black with two wavy yellow lines running down the length of its back (striped flea beetle or Phyllotreta striolata). They overwinter as adults under plant material along field margins and females lay eggs in the soil near the host plants. 

Striped and crucifer flea beetles feed on canola, mustard and related cruciferous plants and weeds. Their damage results in a shot-hole appearance in cotyledon leaves. They also feed on stems under windy or damp conditions, causing wilting or breakage. Remember, the Action Threshold for flea beetles on canola is when 25% of cotyledon leaf area is consumed



For more information on flea beetles, refer to the Insect of the Week page!

Crucifer flea beetle and damage
Photo: AAFC
Flea beetle damage on cotyledon
Photo: Mike Dolinski, MikeDolinski@hotmail.com

Insect of the Week – Dingy cutworm

For many, seed isn’t even in the ground yet, but the cutworms are ready for it when it is. So the time to start scouting for cutworms is now! Even if it is too wet to seed, consider checking volunteer plants for cutworms or feeding damage. General cutworm monitoring protocols can be found on the Monitoring Protocols page. Species-specific protocols can be found in the new Cutworm Pests of Crops on the Canadian Prairies (see below for download details).


There are over 20 cutworm species that may cause economic damage to your crop, each with different feeding behaviour, preferred hosts and lifecycle. This is why species identification is so important: it helps growers understand what they are up against: determining how and when to scout, knowing whether the cutworm species is found above-ground (climbing) or below-ground, recognizing damage, choosing control options. Species also impacts the most appropriate time of day for monitoring and applying controls.


Action and economic thresholds do exist for many of the cutworm species – please use them. This will help control costs by eliminating unnecessary/un-economic sprays and reduce your impact on non-target insects – insects that include cutworm natural enemies that work in the background to control cutworm populations.


This week’s Insect of the Week is the dingy cutworm. This is an above ground climbing species. Crops are at greatest risk in the spring when partially mature larvae emerge to feed primarily on leaves. The name ‘dingy cutworm’ is generally applied to three closely related species with similar appearance and life cycles.


For more information about dingy cutworms, go to the Insect of Week page.

Dingy cutworm larva (cc John Gavioski, Manitoba Agriculture)


Remember the NEW Cutworm Field Guide is free and downloadable in 2017!

Weekly Update – Greetings!

Greetings!

Access the complete Weekly Update either as a series of Posts for Week 4 (May 25, 2017) OR downloadable PDF version.



Questions or problems accessing the contents of this Weekly Update?  Please e-mail either Dr. Owen Olfert or Jennifer Otani.  Past “Weekly Updates” can be accessed on our Weekly Update page.

Subscribe to the Blog by following these easy steps!

Weekly Update – Weather Synopsis

Weather synopsis – This week’s average temperatures were approximately 3°C cooler than normal (Fig. 1) and seven day precipitation accumulations were above normal.  The 30-day rainfall amounts were below average in eastern Saskatchewan and Manitoba (Fig. 2)


The map below reflects the Accumulated Precipitation for the Growing Season so far for the prairie provinces (i.e., April 1-May 24, 2017):


The map below shows the Lowest Temperatures the Past 7 Days (May 18-24, 2017) across the prairies:


Whereas the map below shows the Highest Temperatures the Past 7 Days (May 18-24, 2017):


The updated growing degree day map (GDD) (Base 5ºC, March 1 – May 22, 2017) is below:



While the growing degree day map (GDD) (Base 10ºC, March 1 – May 22, 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.

2017 Wind Trajectories

THE WEEK OF MAY 23, 2017:  Wind trajectory data processing by AAFC-Saskatoon Staff began in April.  Reverse Trajectories track arriving air masses back to their point of origin while Forward Trajectories predict favourable winds expected to arrive across the Canadian Prairies for the week of May 23, 2017:

Reverse trajectories (RT)

Between May 16 and 23 there were 57 RT’s from the Pacific Northwest of USA that crossed the prairies. The first chart (Fig. 1) indicates site specific results for PNW RT’s for each day of the past week. Values reflect the fact that PNW RT’s were lower this week than previous weeks. The greatest number of PNW RT’s continued to be across southern AB (Fig. 2).

Figure 1. Cumulative number of Reverse Trajectories (RT) originating from the Pacific Northwest arriving across the Canadian prairies from May 16-23, 2017 (Olfert et al. 2017).


Figure 2. Number of Reverse Trajectories (RT) originating in the Pacific Northwest that arrived at sites across the Canadian prairies from April 1-May 23, 2017.



Forward trajectories (FT)
No FTs originating from Mexico or southwest USA/Mexico are predicted to cross the prairies over the next 5 days.  The following map provides an overview of FTs that have crossed the prairies during the 2017 growing season.

Figure 2.  Total number of reverse trajectories originating from the Pacific Northwest of the USA arriving at sites across the Canadian prairies (April 1-May 23, 2017).


Weather forecasts (7 day):

Weekly Update – Flea beetles

Flea Beetles (Chrysomelidae: Phyllotreta species) – Be on the lookout for flea beetle damage resulting from feeding on canola cotyledons but also on the stem.  Two species, Phyllotreta striolata and P. cruciferae, will feed on all cruciferous plants but they can cause economic levels of damage in canola during the seedling stages.



Remember, the Action Threshold for flea beetles on canola is 25% of cotyledon leaf area consumed.  Watch for shot-hole feeding in seedling canola but also watch the growing point and stems of seedlings which are particularly vulnerable to flea beetle feeding.


Estimating flea beetle feeding damage can be challenging.  Using a visual guide to estimate damage can be helpful.  Canola Watch circulated this article but also use the two images (copied below for reference) produced by Dr. J. Soroka (AAFC-Saskatoon)  – take it scouting!

Figure 1. Canola cotyledons with various percentages of leaf area consume owing to flea beetle feeding damage (Photo: Soroka & Underwood, AAFC-Saskatoon).

Figure 2.  Percent leaf area consumed by flea beetles feeding on canola seedlings (Photo: Soroka & Underwood, AAFC-Saskatoon).



Refer to the flea beetle page from 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 – Cutworms

Cutworms (Noctuidae) – NEW – Just in time for spring scouting!  A new field guide is now available to help growers scout and manage Cutworms!  Cutworm Pest of Crops is now available for free in either English or French and is featured at our new Cutworm Field Guide!  Also be sure to check the Insect of the Week throughout May – it highlights cutworms!  Be sure to read more about Dingy cutworms.


Dingy cutworm larva (cc John Gavloski, Manitoba Agriculture)

Several species of cutworms can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  Cutworm biology, species information, plus monitoring recommendations are available in the Prairie Pest Monitoring Network’s Cutworm Monitoring Protocol.  Also refer to the Manitoba Agriculture cutworm fact sheet which includes action and economic thresholds for cutworms in several crops. 

Keep an eye on fields that are “slow” to emerge, are missing rows, include wilting or yellowing plants, have bare patches, or appear highly attractive to birds – these are areas warranting a closer look.  Plan to follow-up by walking these areas later in the day when some cutworm species move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of a symptomatic plant or the adjacent healthy plant.  If the plant is well-established, check within the crown in addition to the adjacent soil.  The culprits could be wireworms or cutworms.  


For Albertans….. If you find cutworms, please consider using the Alberta Pest Surveillance Network’s “2017 Cutworm Reporting Tool”.  The map now has reports of pale western and redbacked cutworms in central and southern Alberta so view the live 2017 cutworm map.


Remember the NEW Cutworm Field Guide is free and downloadable in 2017!

Weekly Update – Cereal leaf beetle

Cereal leaf beetle (Oulema melanopus) – As of May 22, 2017, the CLB model indicates that oviposition is well underway across the southern prairies. Compared to southern Alberta and Saskatchewan, populations in southern Manitoba are predicted to be delayed by approximately five days (Fig. 1). Compared to 2016, development in 2017 is approximately 1 week later. Hatch is predicted to occur in isolated areas. 

Lifecycle and Damage:
Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Fig. 2). 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 shelter belts, deciduous and conifer forests. They emerge in the spring once temperature reaches 10-15 ºC and are active for about 6 weeks. They usually begin feeding on grasses, then move into winter cereals and later into spring cereals.  

Figure 2. Adult Oulema melanopus (~4.4-5.5 mm long).


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 (Fig. 3).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 3.  Larval stage of Oulema melanopus with characteristic feeding damage visible on leaf.


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.

Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the new “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide”.

Weekly Update – Pea leaf weevil

Pea Leaf Weevil (Sitona lineatus– The pea leaf weevil simulation model will be used to monitor weevil development across the prairies. Weekly temperature data collected across the prairies is incorporated into the simulation model which calculates estimates of weevil development stages based on biological parameters for Sitona lineatus.


The PLW model was run for Lethbridge AB and Saskatoon SK. Meteorological data (April 1 – May 15, 2017) and climate data (May 16- June 30) were used to predict PLW phenology.  Output indicates that PLW oviposition in Lethbridge is approximately one week earlier than Saskatoon.  Reminder – Access last week’s PLW model output predictions here.

Pea leaf weevils emerge in the spring primarily by flying (at temperatures above 17ºC) or they may walk short distances. Pea leaf weevil movement into peas and faba beans is achieved primarily through flight.  Adults are slender, greyish-brown measuring approximately 5 mm in length (Fig. 1, Left).  

The 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).


Adults will feed upon the leaf margins and growing points of legume seedlings (alfalfa, clover, dry beans, faba beans, peas) and produce a characteristic, scalloped (notched) edge.  Females lay 1000 to 1500 eggs in the soil either near or on developing pea or faba bean plants from May to June.


Biological and monitoring information related to pea leaf weevil in field crops is posted by the province of Alberta.  Also refer to the pea leaf weevil page within the “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.  A review of this insect was published in 2011 in Prairie Soils and Crops by Carcamo and Vankosky.

Weekly Update – Alfalfa weevil

Alfalfa Weevil (Hypera postica) – The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer”.  The green larva featuring a dorsal, white line down the length of its body has a dark brown head capsule and will grow to 9mm long.  Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).



Degree-day maps of base 9°C are now being produced by Soroka, Olfert, and Giffen (2016) using the Harcourt/North Dakota models.  Models predicting the development of Alfalfa weevil (Hypera postica) across the prairies are updated weekly to help growers time their in-field scouting for second-instar larvae.  Compare the following predicted development stages and degree-day values from Soroka (2015) to the map below.



This week, embryological development is greatest across south and central regions of Alberta and Saskatchewan and across southern Manitoba. Early hatch is predicted to occur in a region near Brooks AB and Regina SK and south to the USA border.



Use the figure below as a visual reference to identify alfalfa weevil larvae.  Note the white dorsal line, the tapered shape of the abdomen and the dark head capsule.

Additional information can be accessed by reviewing the Alfalfa Weevil Page extracted from the “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide” (Philip et al. 2015).  The guide is available in both a free 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 – Wheat midge

Wheat Midge (Sitodiplosis mosellana– Predictive modelling will be used again to help  forecast wheat midge emergence across the Canadian prairies.  The maps below predicts the geographic distribution and corresponding accumulation of heat units necessary for wheat midge to emerge from puparia developing in the soil.  


For the week of May 24, 2017, soil moisture and temperature conditions appear to be conducive for wheat midge development. The wheat midge model indicates that wheat midge larvae should be moving to the soil surface by the end of May


Reminder – Back in January, the 2017 Wheat midge forecast map was released along with the other Risk and Forecast maps. It’s posted again below for reference.



Information related to wheat midge biology and monitoring can be accessed by linking to your provincial fact sheet (Saskatchewan Agriculture or Alberta Agriculture & Forestry).  A review of wheat midge on the Canadian prairies was published by Elliott, Olfert, and Hartley in 2011.


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.

Weekly Update – Predicted Bertha Armyworm Development

Bertha armyworm (Lepidoptera: Mamestra configurata– This week, predicted pupal development is well underway. Average development is 36% (27% last week); average development is 37% (Fig. 1). 

Figure 1. Predicted stage of pupal development of overwintered Bertha armyworm set to emerge in 2017.


Reminder – These maps will be updated weekly to aid those who deploy and monitor this moth using pheromone traps.  The video below posted by Alberta Agriculture and Forestry’s Scott Meers describes how pheromone traps are used to monitor this important pest of canola.



Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of ManitobaSaskatchewanAlberta and the Prairie Pest Monitoring Network.  Also refer to the bertha armyworm 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.

Provincial Insect Pest Reports

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 will be posted soon. Watch for updates prepared by John Gavloski and Pratisara Bajracharya). Reports from 2016 can be reviewed here.

Saskatchewan’s Crop Production News for 2017 will be posted soon. Watch for updates prepared by Scott Hartley and Danielle Stephens.  

Watch for Alberta Agriculture and Forestry’s Call of the Land which featured reminders and links to help growers scout for cutworms from Scott Meers (May 25, 2017) plus information related to tick surveillance and Lyme disease (May 25, 2017).

Crop reports

Crop reports are produced by:
• Manitoba Agriculture, Rural Development (May 24, 2017)
• Saskatchewan Agriculture Crop Report (May 16-22, 2017)
• Alberta Agriculture and Forestry Crop Report (May 16, 2017)

International reports are produced by:
• The United States Department of Agriculture’s Crop Progress Report (May 22, 2017)

Weekly Update – Lily leaf beetle

Wondering what that red beetle feeding on your lilies might be?  Read more about the Lily leaf beetle and compare photos here to see if it’s in in your flower beds.

Weekly Update – Monarch migration

We again track the migration of the Monarch butterflies as they move north by checking the 2017 Monarch Migration Map!  A screen shot of the map has been placed below as an example (retrieved 26May2017) but follow the hyperlink to check the interactive map!  They’ve migrated into southern Ontario! 


Weekly Update – Ticks and Lyme Disease

As the spring weather improves and people are active outdoors, remember to watch for ticks.  Blacklegged (deer) ticks are important because they can carry Lyme Disease.  Endemic and risk areas for Lyme disease have been mapped in Canada (Fig. 1).  Continued surveillance activities conducted by Health Canada and the provinces remain important and you can help by identifying / removing / submitting your ticks!

Follow the links to learn more and to submit ticks if you live in British Columbia, Alberta, Saskatchewan, Manitoba, Ontario, or Quebec.
Figure 1. Screenshot of Health Canada’s map of Lyme disease endemic and risk areas in Canada (retrieved 26May2017).

Weekly Update – Previous Posts

The following is a list of 2017 Posts – click to review:


Canola scouting chart

Crop protection guides


Diamondback moth



Flax scouting chart



Iceberg reports

Weekly Update

The Weekly Update received additional data and was updated on Friday.  Please be sure to read over the updated sections for Week 4 (May 25, 2016) which include:

  • Updated Weather Synopsis
  • Updated Pea Leaf Weevil Status
  • Updated Grasshopper Model Outputs (embronic development and progression of hatch)
  • Updated Cereal Leaf Beetle Model Outputs
  • Wheat Midge Model Outputs
  • Lygus Model Outputs

To read the entire Weekly Update for Week 4, you can either:
  1. Search the Blog for “Week 4” or,
  2. Under the LABEL menu on the right side of your screen, click “Week 4 (May 25, 2016)” so the Blog sorts all Posts.

The updated and downloadable PDF of the Weekly Update for Week 4 is available here and the hyperlink within the original Post has also been updated.

Weekly Update – Greetings!

A downloadable PDF version of the complete Weekly Update for Week 4 (May 25, 2016) can be accessed here.

Subscribe to the Blog by following the instructions posted here!  You can receive automatic updates in your inbox through the growing season.


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.  

Wind Trajectories

THE WEEK OF MAY 24, 2016:  Wind trajectory data processing by AAFC-Saskatoon Staff began in April.  Reverse Trajectories track arriving air masses back to their point of origin while Forward Trajectories predict favourable winds expected to arrive across the Canadian Prairies for the week of May 24, 2016:


Reverse trajectories (RT) – Mexico and southwest USA
Compared to 2015, the number of reverse trajectories crossing the prairies is greater in 2016.  Since April 1, there have been 18 prairie locations that have had RT’s originating from southwest USA. This compares with 12 for the same time last year. 

Reverse Trajectories originating from Mexico and southwest USA between April 1-May 24, 2016:





…..Compared to last year!






Diamondback moth

Diamondback moth (Plutellidae: Plutella xylostella) – Pheromone traps attracting male Diamondback moths (Fig. 1) have been deployed across the prairies.  

Figure 1. Diamondback moth.



Counts will be reported by the provincial staff in Saskatchewan.  Manitoba Agriculture and Rural Initiatives posted low DBM counts which can be reviewed within their second Insect Report.  Alberta Agriculture and Forestry has a live 2016 map reporting Diamondback moth pheromone trap interceptions.  A copy of the map (retrieved May 25, 2016) is below for reference.





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 (Fig. 2) dislodged from the plant. Repeat this procedure at least in five locations in the field to get an accurate count.

Figure 2. Diamondback larva measuring ~8mm long.
Note brown head capsule and forked appearance of prolegs on posterior.




Figure 3. Diamondback moth pupa within silken cocoon.

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).


Biological and monitoring information for DBM is posted by Manitoba Agriculture, Food and Rural DevelopmentSaskatchewan AgricultureAlberta Agriculture and Forestry, and the Prairie Pest Monitoring Network.  

More information about Diamondback moths 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 Diamondback moth page but remember the guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.


Weekly Update – Cutworms

Reminder – Cutworms (Noctuidae) – Keep an eye on fields that are “slow” to emerge, are missing rows, include wilting or yellowing plants, have bare patches, or appear highly attractive to birds – these are areas warranting a closer look.  Plan to follow-up by walking these areas later in the day when some cutworm species move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of a symptomatic plant or the adjacent healthy plant.  If the plant is well-established, check within the crown in addition to the adjacent soil.  The culprits could be wireworms or cutworms.  

Several species of cutworms  can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  Cutworm biology, species information, plus monitoring recommendations are available in the Prairie Pest Monitoring Network’s Cutworm Monitoring Protocol.  Also refer to Manitoba Agriculture and Rural Initiatives cutworm fact sheet which includes action and economic thresholds for cutworms in several crops. 

More information about cutworms 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 an excerpt of ONLY the Cutworm pages from the new “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide”.  The guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.



For Manitobans….The most recent Insect Update includes great photos of dingy and redbacked cutworms plus monitoring tips which include how to discern these two species from one another.

For Albertans….. Cutworms have been reported throughout the province the past week!  If you find cutworms, please consider using the Alberta Pest Surveillance Network’s “2016 Cutworm Reporting Tool”.  Once data entry occurs, your growers can view the live 2016 cutworm map.

A screen shot of the live map has been retrieved (25May2016) below for your reference.


Weekly Update – Pea leaf weevil update

Pea leaf weevil monitoring is underway in Alberta and Saskatchewan.  Despite the common name, Sitona lineolatus, will feed on several species of legumes including faba beans, seedling alfalfa, dry beans and of course peas!


Thanks to Dr. Hector Carcamo (AAFC-Lethbridge) for the following update (24May2016):
A mild winter and a very warm and early spring have contributed to what looks like the worst outbreak of pea leaf weevil in southern Alberta. Weevil densities appear to be high enough to be threatening stand establishment of peas this year.


Normally, adult feeding damage has little consequence whereas the main concern is related to larval feeding damage to nitrogen fixing nodules.  That’s NOT the case this year – several growers are spraying for PLW in peas because small seedlings are suffering very high defoliation resulting in stand reductions – something seen previously only in seedling alfalfa stands. Additionally, this year some stands treated with a registered neonicotinoid insecticide have required foliar spraying; the insecticide seed treatment may not provide sufficient protection when weevil densities are extremely high.  Growers hoping to prevent yield losses may consider supplementing with nitrogen during the seedling stage but be cautious – the economic returns should be carefully considered, given input prices.  Finally, be mindful that PLW adults emerge from overwintering over several weeks so sprayed fields may be repeatedly invaded – continued monitoring is a necessity!

Weevils have natural enemies such as ground dwelling beetles that feed on their eggs. The best way to protect natural enemies is to avoid foliar applications of insecticide unless damage reaches the economic threshold of 30% of seedlings with damage on the clam leaf (i.e., assess using 10 transects of 10 seedlings, half near the edge and half inside the field).


Thanks to Scott Hartley (Sask Ag) who noted (25May2016) that PLW surveying is underway in the southwestern Saskatchewan (i.e., as far north as Kindersley / Outlook and east to mid-way between Swift Current and Moose Jaw).   Preliminary reports include  high levels of feeding in several areas in the southwest.  Crops were generally seeded earlier this year than in the past few years. Seed treatments are considered the best control for the pea leaf weevil but, if 30% of plants are showing damage, a foliar insecticide could be required but this strategy is not as consistently effective as a seed treatment. Foliar insecticide may be necessary if plants are very young and therefore more vulnerable to heavy feeding pressure. Remember plants can outgrow PLW damage once they are past the 6th node stage.



Also refer to previous PLW posts for additional information!
Weekly Update from May 18, 2016
Insect of the Week from 2015
Pea leaf weevil in Central Alberta in 2015
The PPMN’s Pea leaf weevil monitoring protocol

Weekly Update – Alfalfa weevil

Alfalfa Weevil (Hypera postica) – The larval stage of this weevil feeds on alfalfa leaves in a manner that characterizes the pest as a “skeletonizer”.  The green larva featuring a dorsal, white line down the length of its body has a dark brown head capsule and will grow to 9mm long.  Alfalfa growers are encouraged to check the Alfalfa Weevil Fact Sheet prepared by Dr. Julie Soroka (AAFC-Saskatoon).


Degree-day maps of base 9°C are now being produced by Soroka, Olfert, and Giffen (2016) using the Harcourt/North Dakota models.  The aim or the modelling is to predict the development of Alfalfa weevil (Hypera postica) across the prairies and to help growers time their in-field scouting as second-instar larvae are predicted to occur.  Compare the following predicted development stages and degree-day values copied below (Soroka 2015) to the map below.



This week, alfalfa growers situated within ANY shade of purple should prioritize scouting for second instar larvae and compare it to the action threshold for alfalfa weevil which varies according to end use and crop stage.  


Weekly Update – Predicted Bertha Armyworm Development

Bertha armyworm (Lepidoptera: Mamestra configurata– Bertha armyworm (BAW) pupal development is progressing well, particularly across AB.  Pheromone traps should be deployed in areas highlighted yellow in the map below.





Those monitoring BAW pheromone traps may want to compare trap “catches” to the following reference photo kindly shared by Saskatchewan Agriculture below:


Weekly Update – Cereal leaf beetle predictions

Cereal leaf beetle (Oulema melanopus) – The following are results from the bioclimate model which predicts cereal leaf beetle (CLB) populations.




As of May 23, 2016, the CLB model indicated that oviposition is well underway: 

  • In Alberta and western Saskatchewan, development was similar to the previous week.
  • Warmer conditions in eastern Saskatchewan and Manitoba resulted in faster development. 
  • Larval populations are predicted to peak in mid-June across most locations in the southern prairies.

Predicted dates of peak emergence of CLB eggs and larvae:



The following model outputs have been updated this week and reflect the predicted stages of CLB present in fields in relation to its parasitoid, Tetrastichus julis














Fact sheets for CLB are published by the province of Alberta and available from the Prairie Pest Monitoring Network. Also access the Oulema melanopus page from the new “Field crop and forage pests and their natural enemies in western Canada – Identification and management field guide”.

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 – Wheat midge

Wheat Midge (Sitodiplosis mosellana) – Predictive modelling will be used again to help  forecast wheat midge emergence across the Canadian prairies.  The maps below predicts the geographic distribution and corresponding accumulation of heat units necessary for wheat midge to emerge from puparia developing in the soil.  

For the week of May 23, 2016, model runs for Saskatoon SK and Fairview AB presented similar results. Unlike last year when dry soil moisture limited development, soil moisture conditions appear to be suitable for wheat midge development in the soil. Output indicates that larvae should be moving to the soil surface later this week. 









Information related to wheat midge biology and monitoring can be accessed by linking to your provincial fact sheet (Saskatchewan Agriculture or Alberta Agriculture & Forestry).  A review of wheat midge on the Canadian prairies was published by Elliott, Olfert, and Hartley in 2011.

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.

Provincial Insect Pest Reports

Provincial entomologists provide insect pest updates throughout the growing season so we have attempted to link to their most recent information: 

– Manitoba’s Insect preview article (May 25, 2016, published by the Manitoba Cooperator).
– Saskatchewan’s Insect Pest Outlook article (April 7, 2016,  published by the Western Producer).
– Watch for Alberta Agriculture and Forestry’s Call of the Land for updates from Scott Meers  (posted on May 19, 2016).


Weekly Update – Crop reports

Crop reports are produced by:

– Manitoba Agriculture, Rural Development (May 23, 2016)
– Saskatchewan Agriculture Crop Report (May 16, 2016)
– Alberta Agriculture and Forestry (for May 17, 2016)


Reminder – International reports are produced by:

The United States Department of Agriculture’s Crop Progress Report (May 23, 2016)
The European Commission’s Agriculture and Rural Development report on Short-term Outlook for EU Arable Crops, Dairy and Meat Markets (Winter issue).

Weekly Update – Crop Protection Guides

Reminder – Crop Protection Guides – If you don’t have a copy of your province’s Crop Protection Guide, please make use of these links to access:

Weekly Update – Weather Synopsis

Across the prairies, meteorological conditions were similar to long term average values for May 16-23, 2016. The average temperature was 11.1 °C and was much warmer than the previous seven days (8.7 °C) and was 1 °C warmer than the average temperature.  Temperatures were generally warmer in Manitoba and eastern Saskatchewan than western Saskatchewan and Alberta.


This past week, many Albertan locations reported significant rainfall amounts while minimal amounts were reported for Saskatchewan and Manitoba.  


The map below shows the Accumulated Precipitation the past 7 days (i.e., May 16-23, 2016) which fell as both rain and snow in the west: 


The map below reflects the Accumulated Precipitation for the Growing Season so far for the prairie provinces (i.e., April 1-May 24, 2016):




Compared to last week, soil moisture levels were predicted improve across most of Alberta.  Lower soil moisture values were predicted across most of Saskatchewan.


Again cooler temperatures put newly emerging crops at risk.  The map below shows the Lowest Temperatures the Past 7 Days (May 18-24, 2016) across the prairies:

The map below shows the Highest Temperatures the Past 7 Days (May 18-24, 2016):

The updated growing degree day map (GDD) (Base 5ºC, March 1 – May 23, 2016) is below:





While the growing degree day map (GDD) (Base 10ºC, March 1 – May 23, 2016) 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.

Weekly Update – Canola scouting chart

We again post our generalized canola scouting chart to aid in-field scouting on the Canadian prairies. The version below contains hyperlinks to help growers learn more about some of our insect pests and how to monitor for them.



Weekly Update – Flea beetles

Reminder – Flea Beetles (Chrysomelidae: Phyllotreta species) – Remember, the Action Threshold for flea beetles on canola is 25% of cotyledon leaf area consumed.  Shot-hole feeding is the traditional damage in seedling canola but watch the growing point and stems of seedlings.

Estimating flea beetle feeding damage can be challenging.  Using a visual guide to estimate damage can be helpful.  Canola Watch circulated this article but also use the images (copied below for reference) produced by Dr. J. Soroka (AAFC-Saskatoon)  – take it scouting!

Figure 1. Canola cotyledons with various percentages of leaf area consume owing to flea beetle feeding damage (Photo: Soroka & Underwood, AAFC-Saskatoon).


Figure 2.  Percent leaf area consumed by flea beetles feeding on canola seedlings (Photo: Soroka & Underwood, AAFC-Saskatoon).

Refer to the flea beetle page from 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.


Also refer to the previous Flea beetle post on the Blog.



Weekly Update – Pea leaf weevil

Pea leaf weevil (Sitona lineatus) – Pea leaf weevils emerge in the spring primarily by flying (at temperatures above 17ºC) or they may walk short distances. Pea leaf weevil movement into peas and faba beans is achieved primarily through flight.  Adults are slender, greyish-brown measuring approximately 5 mm in length (Figure 1).

Figure 1. The pea leaf weevil, Sitona lineatus, measures ~5mm long (Photo: H. Goulet).



The pea leaf weevil resembles the sweet clover weevil (Sitona cylindricollis) yet the former is distinguished by three light-coloured stripes extending length-wise down thorax and sometimes the abdomen (Link here for the Pea leaf weevil monitoring protocol with photos of related weevils).  All species of Sitona, including the pea leaf weevil, have a short snout.


Adults will feed upon the leaf margins and growing points of legume seedlings (alfalfa, clover, dry beans, faba beans, peas) and produce a characteristic, scalloped (notched) edge (Figure 2).  Females lay 1000 to 1500 eggs in the soil either near or on developing pea or faba bean plants from May to June.

Figure 2. Feeding notches on clam leaf of pea plant resulting from pea leaf weevil (Photo: L. Dosdall).

Weekly Update – Lygus bugs

Lygus bugs (Lygus spp.) – Model runs for Lygus suggest that oviposition should begin later this week at Saskatoon and 10-14 days later at Lethbridge.







Information related to Lygus bug biology and monitoring can be accessed by linking to your provincial fact sheet (Manitoba Agriculture and Rural Initiatives or Alberta Agriculture & Forestry).  

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 Lygus bug pages, or Alfalfa plant bug, or Superb plant bug pages but remember the guide is available as a free downloadable document as both an English-enhanced or French-enhanced version.

Pea Leaf Weevil in Central Alberta

Previous reports and surveys performed by Alberta Agriculture and Rural Development’s Meers and Barkley confirmed the presence of Pea leaf weevil (Sitona lineatus) in the Red Deer region recently.

This week, faba bean plots at AAFC-Lacombe were observed to have suffered feeding damage from this introduced weevil species (note notching of leaves in photos below).  The damage was characterized by P. Reid as <10% foliage consumed which isn’t expected to affect yield according to H. Carcamo (AAFC-Lethbridge) who also posited that faba beans may tolerate more PLW feeding damage than peas owing to the fact that they produce more nodules and are recognized as the best nitrogen-fixing pulse crop.

***See Insect of the Week from June 1 for more information (description, damage, management options, etc) on the pea leaf weevil from the new Field Crop and Forage pests and their Natural Enemies in Western Canada***

Wind Trajectories

Wind trajectories Related to Diamondback Moth (DBM) and Aster Leafhopper
Introductions to the Canadian Prairies in 2015

BACKGROUND:
  Potential wind events capable of carrying insect pests
from source areas in the USA can be identified by following trajectories for
air parcels through time. 
High altitude air masses, originating
from southern locations, frequently move northerly to Canadian destinations.
Insect pest species such as Diamondback moth and Aster leafhoppers,
traditionally unable to overwinter above the 49th parallel, can utilize these
air masses in the spring to move north from Mexico and the United States
(southern or Pacific northwest).
Wind trajectory data processing by AAFC-Saskatoon Staff (Weiss &
Olfert) began in April.  Reverse Trajectories track air
masses arriving across the prairies back to their point of origin.  Forward
Trajectories
 predict favorable winds expected to arrive
across the Canadian Prairies.  
Updated: May 23-25, 2015
1.  Reverse trajectories (RT)
This week, RTs are originating over the Arctic, tracking south to pass
over South and North Dakota and tracking north into the Canadian prairies.
2.  Forward trajectories (FT) 
This week, Environment Canada models project that FTs crossing the
prairies are expected to originate from the following sites:
Location
Projected
Arrival Dates
BOZEMAN_MONTANA
25/05/2015
EASTERN_WASHINGTON
25/05/2015
MOSCOW_IDAHO
25/05/2015
EASTERN_WASHINGTON
24/05/2015
MANHATTAN_KANSAS
24/05/2015
MOSCOW_IDAHO
24/05/2015
BROWNSVILLE_TEXAS
23/05/2015
EASTERN_WASHINGTON
23/05/2015
MOSCOW_IDAHO
23/05/2015

Insect of the Week – Diamondback moth

In follow-up to Scott Hartley’s observations, this week’s Insect of the Week highlights diamondback moth (from the new Field Crop and Forage Pests and their Natural Enemies in Western Canada – Identification and Management Field Guide). See also Insect of the Week from May 11 for flea beetle description, scouting and management options.