2018 Wind trajectories (April 1 - May 10, 2018; Wk 01)

Background.  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 1990's. 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 (RT) and forward trajectories (FT): 
(i) Reverse trajectories 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.). RTs are the best available estimate of 3D wind fields at a specific point. They are based on observations, satellite and radiosonde data. 

(ii) Forward trajectories 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 to us are the winds that eventually end up passing over the Prairies. 

Current Data

Pacific Northwest (PNW) – The number of RTs predicted to cross the prairies from the PNW, has increased over the last few days. Model runs for May 7th predicted that seven RTs will cross over AB and SK in the next 24 hours from the PNW. Based on results for April, there have been fewer RTs in 2018 than 2017. The number of RTs were greatest across southern AB (Fig. 1). The majority of these crossed the prairies in mid-April (Fig. 2).

Figure 1. Total number of reverse trajectories, originating over the US PNW, that
has entered the prairies during April, 2018.

Figure 2. Daily total number of reverse trajectories, originating over the US PNW, that
have entered the prairies during April, 2018.

Weather forecasts (7 day):

Winnipeg: https://weather.gc.ca/city/pages/mb-38_metric_e.html
Brandon: https://weather.gc.ca/city/pages/mb-52_metric_e.html
Saskatoon: https://weather.gc.ca/city/pages/sk-40_metric_e.html
Regina: https://weather.gc.ca/city/pages/sk-32_metric_e.html
Edmonton: https://weather.gc.ca/city/pages/ab-50_metric_e.html
Lethbridge: https://weather.gc.ca/city/pages/ab-30_metric_e.html
Grande Prairie: https://weather.gc.ca/city/pages/ab-31_metric_e.html 

Cutworms (May 10, 2018; Wk 01)

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!  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.  

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.

Flea beetles (May 10, 2018; Wk 01)

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.

Cereal leaf beetle (May 10, 2018; Wk 01)

Cereal leaf beetle (Oulema melanopus) - Model output indicates that CLB oviposition has begun in many locations.  As of May 6th, CLB model runs indicated that cool temperatures have delayed oviposition (compared to long term average) in Lethbridge, but more advanced in Swift Current, Brandon and Saskatoon (Fig. 1). 

Figure 1.  Predicted CLB oviposition at four prairie locations. Values are based on 
model simulations, for April 1 – May 6, 2018.

Lifecycle and Damage:

Adult: Adult cereal leaf beetles (CLB) have shiny bluish-black wing-covers (Fig. 1). 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 1. 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. 2).  When the larva completes its growth, it drops to the ground and pupates in the soil. 

Figure 2.  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".

Pea leaf weevil (May 10, 2018; Wk 01)

Pea Leaf Weevil (Sitona lineatus) – The PLW model predicts that adults are emerging from overwintering sites and beginning to fly. This is similar to model output based on long term (climate) data.  Looking forward, based on long term average climate data, oviposition should occur in late May or early June (Fig. 1).

Figure 1. Predicted PLW phenology at Swift Current based on long term climate data. Values are
based on model simulations (April 1 – May 6).

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 1.  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.

Predicted grasshopper development (May 10, 2018; Wk 01)

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

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

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

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

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

Alfalfa weevil (May 10, 2018; Wk 01)

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. Compare the following predicted development stages and degree-day values from Soroka (2015) to the map below.

The AAW model predicts that oviposition may have begun in southern areas of the prairies. Current oviposition rates are predicted to be higher than oviposition rates based on  LTN climate data (Fig. 1).

 Figure 1. Predicted AAW oviposition at four prairie locations. Values are based on
model simulations, for April 1 – May 6, 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.

Predicted bertha armyworm development (May 10, 2018; Wk 01)

Bertha armyworm (Lepidoptera: Mamestra configurata) - Bertha armyworm pupal development is predicted below.   The map illustrates that overwintered BAW are beginning to develop within their pupa located in the soil but are still several weeks away from emerging as moths.  

Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of Manitoba, Saskatchewan, Alberta and the Prairie Pest Monitoring Network.  Also refer to the bertha armyworm pages within the 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.

Scouting Charts - Canola and Flax (May 10, 2018; Wk 01)

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
    

2. A NEW FLAX INSECT SCOUTING CHART
    
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!

Are cereal aphids damaging your crops? There's now an app for that: Cereal Aphid Manager (CAM)

Aphids can cause significant damage to fields and increase crop losses, but just because aphids are present in a grain field doesn’t mean they will have a negative economic impact on production. This is especially true if there are aphid’s natural enemies (beneficial insects) in the field to keep them under control.

The Cereal Aphid Manager is an easy-to-use mobile app that helps farmers and crop advisors control aphid populations in wheat, barley, oat or rye. It is based on Dr. Tyler Wist's (Agriculture and Agri-Food Canada Field Crop Entomologist) innovative Dynamic Action Threshold model. The model treats the grain field as an ecosystem and takes into account many complex biological interactions including:

• the number of aphids observed and how quickly they reproduce
• the number of different natural enemies of aphids in the field and how many aphids they eat or parasitize per day
• the lifecycles of aphids and their enemies taking into account developmental stages, egg laying behaviour, population growth rate, lifespan, etc.

By taking into consideration factors like these, the app predicts what the aphid population will be in seven days and the best time to apply insecticide based on economic thresholds.

Available in iOS and Android.

To learn more and to download, go to AAFC's CAM webpage.

Note: Cereal aphids can blow up from the South at any time which cannot be predicted by the app. Therefore, farmers and crop advisors should regularly check fields during the growing season regardless of what Cereal Aphid Manager Mobile may recommend.

CAM Homepage

CAM monitoring report and recommendation

CAM icon

Back for the 2018 growing season!

Greetings!  The Prairie Pest Monitoring Network's Blog gears up for the 2018 growing season this week!  Today the first "Insect of the Week" was released and watch for the first "Weekly Update" on Friday morning!

Insect of the Week (May 07, 2018) - Glassy cutworm

This week's insect is the glassy cutworm. The larva is greyish-white, semi-translucent and shiny (i.e. glass-like) with a orange-brown head. Since it overwinters as a larva, it is active as soon as the ground thaws. It feeds underground and rarely come to the surface. Their main host crop are grasses but will also attack wheat and corn. Corn planted following wheat may be particularly at risk.

Find out more about the glassy cutworm at the Insect of the Week page.

Glassy cutworm
cc-by Joseph Berger, bugwood.org

Other important species include dingy, army, redbacked and pale western cutworms (See Insect of the Week: 2017 - May 1, 8, 15 and 29).

In addition, Cutworm Pests of Crops on the Canadian Prairies - Identification and Management Field Guide was just published (2017). This new handy field guide has chapters on general biology, history of outbreaks, scouting techniques, natural enemies and general control options. The guide includes descriptions of 24 cutworm species, their lifecycle, hosts, damage, monitoring and economic thresholds. To download a copy, go to the Cutworm Field Guide page.

2017 Swede Midge Pheromone Monitoring Results - Mori, Vankosky

In 2017, swede midge pheromone traps were deployed at 46 sites across the Prairie region to monitor for populations of this brassica pest. Of the 46 trap sites, two were located in BC, 19 in Alberta, 16 in Saskatchewan, and nine in Manitoba. Figure 1 illustrates trap site locations in 2017. Two pheromone traps were deployed at each site.

All of the traps were negative for swede midge in 2017. 

Figure 1.  Pheromone trap site locations for swede midge (Continarinia nasturtii) in 2017.

We are grateful to all of the producers, agronomists, and cooperators who participated in the 2017 swede midge monitoring project. Without your assistance, we could not have supported such a thorough and widespread pheromone monitoring program.

We also extend our thanks to Nancy Melnychuk (AAFC-Saskatoon) for organizing the program and distributing trapping materials, and to Jonathon Williams and Shane Hladun (AAFC-Saskatoon) for examining the returned sticky cards.

Because of the serious threat that swede midge poses to canola production, it is vital that monitoring continues across the Prairies. At this time, plans are being made for the 2018 swede midge monitoring program. Agrologists or growers interested in performing weekly monitoring in 2018 are encouraged to contact Jonathon Williams, Boyd Mori, or Meghan Vankosky for more information.

Boyd Mori and Meghan Vankosky
Agriculture and Agri-Food Canada, Saskatoon Research and Development Centre

More information about swede midge can be found by:

• Referring to the Canola Watch article by Dr. Julie Soroka or accessing a new Ontario fact sheet produced by Baute et al. 2016.
• Accessing the swede midge pages within the new Field Guide which is available as a free download in either English or French.

Blog maintenance (January 8, 2018)

Please be patient - we are working to archive and update the Blog in preparation for the 2018 growing season.

Old bookmarks may be rendered obsolete by our efforts but please try either our "Search this Blog" function (located to the right of this Post) OR please scan our "Label" list by scrolling down this page and looking along the lower right of this screen.  All our information is still here but you may need to update your bookmark.

Thank you for your patience!

Winter Update (Nov 22, 2017; Wk 29) - Greetings!

Greetings!

We've updated a few items on the Blog this week!  Please take a moment to review the short series of Blog Posts put up today. 

Subscribe to the Blog by following these three steps!

Winter Update (Nov 22, 2017; Wk 29) - Why we exist, who we are and a few other things....

NEW - The Blog has been updated with an "About Us" Page.  Readers can find information about the Prairie Pest Monitoring Network and its supporters.  Additional information concerning accessing the Blog's information and its intent is also posted on this Page.

Winter Update (Nov 22, 2017; Wk 29) - Archive activity coming soon!

Blog housekeeping will continue early in January....

The "viewable" PDF versions of the 2017 Weekly Updates will come down at the end of December 2017 on our WEEKLY UPDATE Page.  At the beginning of January 2018, we will archive those files and reduce them to a series of hyperlinks.  That activity may affect people who bookmarked the specific PDF during the growing season!

Rest assured, all the PDFs for 2015, 2016 and 2017 will still be available after December 31st  - just return to the Weekly Update page and scroll down to access the appropriate hyperlink.

Winter Update (Nov 22, 2017; Wk 29) - Recent scientific poster

Research conducted by the Prairie Pest Monitoring Network was recently presented at the 2017 Joint Annual Meetings of the Entomological Society of Canada and Entomological Society of Manitoba.  A PDF copy of that poster is now accessible on our Research Page.  Thank you to the authors and their many cooperators!!

Winter Update (Nov 22, 2017; Wk 29) - Reminder: Field Heroes!

Earlier this growing season the Field Heroes campaign began.  The campaign is supported by Western Grains Research Foundation and is aimed at increasing awareness of naturally occurring arthropods that are beneficial to growers owing to their ability to consumer insect pest species!

Make sure to visit their website to learn more about some of the beneficial arthropods active in agricultural field crops on the prairies and consider following @FieldHeroes in your Twitter feed.

Winter Update (Oct 2, 2017; Wk 22) - True armyworm

Earlier this summer (Week 14), the true armyworm (Lepidoptera: Noctuidae: Mythimna unipuncta) was reported on the lower west coast and a summary was provided by Tracy Hueppelsheuser (BC Ministry of Agriculture).

Tracy kindly provided an update to the situation.... The initial true armyworm damage reported earlier did not relent and a second generation of voracious larvae continued to cause damage in late August through to late September in southwestern British Columbia.  In addition to Vancouver Island (hit a second time), true armyworm larvae showed up south of Abbotsford, Sumas, Matsqui, Dereoche, as well as east through Chilliwack (Greendale, Rosedale), and west all the way to Delta and Westham Island.  The outbreak resulted in damage to grass fields and even corn was defoliated and cobs damaged!  

True armyworm pupae were observed mid-September and moths are expected over the next while in lower BC.  A third generation is anticipated but is not expected to cause as much damage owing to the cooler nights (~8°C) which should slow insect development and feeding.  Parasitism was noted which is good news in terms of natural enemies responding to the outbreak.  Also, lots of bird feeding activity has been observed although the birds' seeking and feeding activities have also damaged grass fields!

The outbreak of true armyworm in lower BC appears to be part of a larger outbreak that has similarly afflicted western Oregon and Washington this year.  

Find more information on true armyworms in the NEW Cutworm Field Guide, free and downloadable in 2017!

Screenshots of true armyworm from the Cutworm Field guide are also shown below: