Weekly Update – Weather synopsis

Ross Weiss, Owen Olfert, David Giffen and Erl Svendsen
Week 3

Across the prairies, meteorological conditions for the period May 8-15, 2016, were similar to long term average values for the first half of May. 

The average temperature was 8.7 °C (12 °C last week) and was 0.7 °C warmer than the average temperature for May 8-15. 

This past week, rainfall amounts were minimal across most of Alberta and southern Manitoba. Most of Saskatchewan received normal or above normal rainfall.  This week rainfall amounts greater than 30 mm were reported for a number of locations across southern Saskatchewan. 

The 30-day rainfall amounts were similar to long term average values.  

Compared to last week, soil moisture levels were predicted to improve across most of Saskatchewan.  Low soil moisture values were predicted across central and northern Alberta.

Unfortunately, there were some cool temperatures just as seedlings were emerging….. 
The map below reflects the Lowest Temperatures occurring over the past 7 days across the prairies.

Whereas the map below reflects the Highest Temperatures occurring over the past 7 days across the prairies.

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.

Wind trajectories

Ross Weiss, Owen Olfert, Serge Trudel and prairiepest_admin
Week 3
2016 Wind Trajectories – High altitude air masses originate from southern locations and continuously 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). Data acquired from Environment Canada is compiled by Olfert et al. (AAFC-Saskatoon) to track and model spring high altitude air masses with respect to potential introductions of insect pests onto the Canadian prairies. 

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.

This week, Reverse Trajectories (RT) originating from southwest USA and Mexico have crossed over more than half of the prairie locations (18 of 29 locations). This week, first reports of these RT’s occurred for Russel MB, Gainsborough SK, Yorkton SK, Grenfell SK, Watrous SK, and Kindersley SK. 

Review earlier 2016 Wind Trajectory Updates in PDF format.

Weather forecasts (7 day):

Weekly Update – Canola scouting chart

Jennifer Otani
Week 3
Field scouting is critical because it enables the identification of potential risks to crops.  Canola production systems across the Canadian prairies will suffer insect pest outbreaks.  However, the identification of these insect pests PLUS the application of established monitoring methods will enable growers to make informed pest management decisions.

We first offered the chart below in 2015 but we again post our generalized canola scouting chart to aid in-field scouting on the Canadian prairies. Two versions are below – the first version contains hyperlinks to help growers learn more about some of our insect pests and how to monitor while the second version may be easier to view or print.  

Whenever possible, monitor and compare to established economic thresholds so pollinators and beneficial arthropods are preserved.  Economic thresholds, by definition, can help growers avoid crop losses due to an insect pest.

Good luck with the growing season!

Weekly Update – Diamondback moth

Jennifer Otani, Scott Meers, John Gavloski and Scott Hartley
Week 3

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

Counts will be reported by the provincial staff in Manitoba and Saskatchewan soon.  Alberta Agriculture and Forestry has posted their live 2016 map reporting Diamondback moth pheromone trap interceptions.  A copy of the map (retrieved May 18, 2016) is below for reference.

Biological and monitoring information for DBM is posted by Manitoba Agriculture, Food and Rural Development, Saskatchewan Agriculture, Alberta 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 – Flea beetles

Jennifer Otani
Week 3

Reminder – Flea Beetles (Chrysomelidae: Phyllotreta species) – Be on the lookout for flea beetle damage resulting from feeding on canola cotyledons but also on the stem.

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.

Weekly Update – Cutworms

Scott Meers, Jennifer Otani and John Gavloski
Week 3

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 ALBERTANS….. If cutworms are spotted in Albertan fields, 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 (18May2016) below for your reference.

Weekly Update – Pea leaf weevil

Ross Weiss, Owen Olfert, David Giffen and Erl Svendsen
Week 3

Reminder – 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.  

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 (Access the Pea leaf weevil monitoring protocol).  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.  Females lay 1000 to 1500 eggs in the soil either near or on developing pea or faba bean plants from May to June.

Information related to Pea leaf weevil in Alberta and the forecast for 2016 is posted here.  

Weekly Update – Cereal leaf beetle predictions

Ross Weiss, Owen Olfert, David Giffen and Erl Svendsen
Week 3

Cereal leaf beetle (Oulema melanopus) – Based on last week’s warm weather, our bioclimate model predicted rapid development of cereal leaf beetle (CLB) populations.

As of May 15, 2016, the CLB model indicated that oviposition is well underway, though this week’s development was slower than the previous week. Model output predicted that egg populations should be peaking this week in both Alberta and Saskatchewan and next week at Swan River  MB. Larval populations are predicted to peak in mid-June in southern Alberta and Saskatchewan and one week later at Swan River MB locations.

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 by 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 Bertha Armyworm Development

Ross Weiss, David Giffen, Owen Olfert and Erl Svendsen
Week 3

Bertha armyworm (Lepidoptera: Mamestra configurata) – Bertha armyworm (BAW) pupal development is progressing well, particularly across AB. Predicted pupal development is greater than 50% at Brooks, Vauxhaul, Hanna, Drumheller, Edmonton, AB and at Kindersley, SK.

Provincial Insect Pest Reports

John Gavloski, Scott Meers, Scott Hartley and prairiepest_admin
Week 3

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

– Manitoba’s Insect preview article (April 18, 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 – Predicted Grasshopper Development

Ross Weiss, Owen Olfert, David Giffen and Erl Svendsen
Week 3

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

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

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

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

Weekly Update

Jennifer Otani, David Giffen, Ross Weiss and Owen Olfert
Week 3

A downloadable PDF version of the complete Weekly Update for Week 3 (May 18, 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.