Predicted bertha armyworm development

Model simulations for August 3, 2020, indicate that BAW development varies across the prairies. Figures 1 and 2 demonstrate that BAW populations near Winnipeg (Fig. 1) are more advanced than populations near Grande Prairie (Fig. 2). Populations near Winnipeg are predicted to be developing to pupae (Fig. 1). BAW populations near Grande Prairie are expected to be primarily in the larval stage (Fig. 2).

Figure 1. Predicted bertha armyworm (Mamestra configurata) phenology at Winnipeg MB as of August 3, 2020.
Figure 2 Predicted bertha armyworm (Mamestra configurata) phenology at Grande Prairie AB as of August 3, 2020.

Weekly Pheromone-baited Trapping Results – Early season detection of bertha armyworm is improved through the use of pheromone-baited unitraps traps deployed in fields across the Canadian prairies.  Click each province name to access moth reporting numbers observed in AlbertaSaskatchewan and Manitoba (as they become available). Check these sites to assess cumulative counts and relative risk in your geographic region but remember in-field scouting is required to apply the economic threshold to manage both this pest and its natural enemies. For convenience, screen shots of the above maps or data have been placed below for Alberta, Saskatchewan, and Manitoba.

Monitoring:

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

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

Refer to the PPMN Bertha armyworm monitoring protocol for help when performing in-field scouting.  Use the images below (Fig. 4) to help identify the economically important larvae.  Review the 2019 Insect of the Week which featured bertha armyworm and its doppelganger, the clover cutworm! 

This image has an empty alt attribute; its file name is 2019_PPMN-Protocol_BAW_LifeStages_Williams.png
Figure 4. The egg stage (A), larval stage (B), pupal stage (C), and adult stage (D) of bertha armyworm. Photos: Jonathon Williams (AAFC-Saskatoon).

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 “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.

Bertha armyworm

Click to link to last week’s information posted for Wk 13 (released 23Jul2020) to review the predictive model outputs for this insect pest. As larvae now begin to develop and feed in fields, emphasis is now placed on in-field scouting in areas where high moth counts are being intercepted by provincial networks highlighted below.

Weekly Pheromone-baited Trapping Results – Early season detection of bertha armyworm is improved through the use of pheromone-baited unitraps traps deployed in fields across the Canadian prairies.  Click each province name to access moth reporting numbers observed in AlbertaSaskatchewan and Manitoba. Remember in-field scouting is required to apply the economic threshold to manage both this pest and its natural enemies. For convenience, screen shots of available maps or data from Alberta, Saskatchewan, and Manitoba are below.

This image has an empty alt attribute; its file name is 2020Jul15_BAW_SK-791x1024.png
This image has an empty alt attribute; its file name is 2020Jul22_BAW_MB.png

Refer to the PPMN Bertha armyworm monitoring protocol for help when performing in-field scouting.  Use the images above (Fig. 4) to help identify the economically important larvae.  Review the 2019 Insect of the Week which featured bertha armyworm and its doppelganger, the clover cutworm! 

This image has an empty alt attribute; its file name is 2019_PPMN-Protocol_BAW_LifeStages_Williams.png
Figure 4. The egg stage (A), larval stage (B), pupal stage (C), and adult stage (D) of bertha armyworm. Photos: Jonathon Williams (AAFC-Saskatoon).

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 “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.

Predicted bertha armyworm development

Model simulations for July 19, 2020 (Fig. 1) indicate that 23% of the bertha armyworm (BAW) population is in the egg stage (compared to 35% last week) and 77% are predicted to be larvae (compared to 65% last week). Across the Parkland and Peace River regions, BAW populations are predicted to be primarily in the egg stage (Fig. 1). Other than the Peace River region, populations are primarily in the larval stage (Fig. 1). Fields near Carman, Winnipeg and Morden in Manitoba are expected to have first appearance of pupae, suggesting larval development is advanced (Fig. 1).

Figure 1. Predicted percent of bertha armyworm (Mamestra configurata) population in the larval stage as of July 19, 2020.

The two graphs below demonstrate that BAW populations near Winnipeg (Fig. 2) are more advanced than populations near Grande Prairie (Fig. 3). In Winnipeg populations are primarily in the larval stage with first appearance of pupae (Fig. 2). BAW populations near Grande Prairie are predicted to be in adult, egg and larval stages (Fig. 3).

Figure 2. Predicted bertha armyworm (Mamestra configurata) phenology at Winnipeg MB as of July 19, 2020.
Figure 3. Predicted bertha armyworm (Mamestra configurata) phenology at Grande Prairie AB as of July 19, 2020.

Weekly Pheromone-baited Trapping Results – Early season detection of bertha armyworm is improved through the use of pheromone-baited unitraps traps deployed in fields across the Canadian prairies.  Click each province name to access moth reporting numbers observed in AlbertaSaskatchewan and Manitoba (as they become available). Check these sites to assess cumulative counts and relative risk in your geographic region but remember in-field scouting is required to apply the economic threshold to manage both this pest and its natural enemies. For convenience, screen shots of the above maps or data have been placed below for Alberta, Saskatchewan, and Manitoba.

Refer to the PPMN Bertha armyworm monitoring protocol for help when performing in-field scouting.  Use the images above (Fig. 4) to help identify the economically important larvae.  Review the 2019 Insect of the Week which featured bertha armyworm and its doppelganger, the clover cutworm! 

This image has an empty alt attribute; its file name is 2019_PPMN-Protocol_BAW_LifeStages_Williams.png
Figure 4. The egg stage (A), larval stage (B), pupal stage (C), and adult stage (D) of bertha armyworm. Photos: Jonathon Williams (AAFC-Saskatoon).

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 “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.

Predicted bertha armyworm development

Model simulations for July 12, 2020 indicate that 35% of the population is in the egg stage (37% last week) and 65% of the population is in the larval stages (14% last week). Across the Parkland and Peace River regions, BAW populations are predicted to be primarily in the egg stage (Fig. 1). Populations across southern regions are primarily in the larval stage (Fig. 1).

Figure 1. Predicted percent of bertha armyworm (Mamestra configurata) population in the larval stage as of July 12, 2020.

The two graphs below demonstrate that larval development near Brandon is predicted to be ahead of fields near Grande Prairie. In Brandon, populations are primarily in the larval stage (Fig. 2) while BAW populations near Grande Prairie are predicted to be predominantly in adult and egg stages (Fig. 3).

Figure 3. Predicted bertha armyworm (Mamestra configurata) phenology at Brandon MB as of July 12, 2020.
Figure 3. Predicted bertha armyworm (Mamestra configurata) phenology at Grande Prairie AB as of July 12, 2020.
Figure 5. The egg stage (A), larval stage (B), pupal stage (C), and adult stage (D) of bertha armyworm. Photos: Jonathon Williams (AAFC-Saskatoon).

Weekly Pheromone-baited Trapping Results – Early season detection of bertha armyworm is improved through the use of pheromone-baited unitraps traps deployed in fields across the Canadian prairies.  Click each province name to access moth reporting numbers observed in AlbertaSaskatchewan and Manitoba (as they become available). Check these sites to assess cumulative counts and relative risk in your geographic region but remember in-field scouting is how the economic threshold is applied to manage this pest.

Refer to the PPMN Bertha armyworm monitoring protocol for help when performing in-field scouting.  Use the images above (Fig. 5) to help identify the economically important larvae.  Review the 2019 Insect of the Week which featured bertha armyworm and its doppelganger, the clover cutworm! 

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 “Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide” which is a free downloadable document as both an English-enhanced or French-enhanced version.

Scouting charts for canola and flax

Reminder – 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 with photos 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.

Scouting Charts – Canola and Flax

Reminder – One last time for this growing season….. We have updated the field scouting charts so they now link to pages within the 2018 version of the Insect Field Guide

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

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 insect pest species but they rely on in-field scouting!

Insect of the Week – Doppelgangers: Bertha armyworm and clover cutworm

The case of the bertha armyworm and the clover cutworm (and other cutworm species)

Clover cutworm larva
cc-by 3.0 Lo Troisfontaine
Bertha armyworm – caterpillar 
Mike Dolinski, MikeDolinski@hotmail.com

Are those bertha armyworms (Mamestra configurata) eating your canola, mustard or alfalfa (also found on lamb’s-quarters, peas, flax, potato)? Or is it maybe a clover cutworm (Discestra trifolii)? [Note: not all cutworm species spend their larval stage underground.] The larvae of the two species are doppelgangers as they are similar in appearance, have a large overlap in host crops, and have similar timing (June-September). Telling them apart can be a challenge but here are few tips to focus on to help distinguish:

Colour:

  • there are generally fewer velvety black clover cutworm caterpillars, with most of the clover cutworm larvae being green or pale brown

Lateral stripe:

  • On the clover cutworm it is yellowish-pink
  • On the bertha armyworm it is yellowish-orange
Climbing cutworm larva – from Cutworm Field Guide
Climbing cutworm adults – from Cutworm Field Guide

In terms of scouting, economic thresholds and control options, treat both species as you would bertha armyworms.

Bertha armyworm – adult
Alberta Agriculture and Rural Development
Clover cutworm adult
cc-by-nc-sa 2.0 Ilona Loser

To learn more about bertha armyworms and clover cutworms, go to the Insect of the Week page or download copies of the Field Crop and Forage Pests andtheir Natural Enemies in Western Canada and Cutworm Pests of Crops onthe Canadian Prairies identification field guides.

Scouting Charts – Canola and Flax

Reminder – We have updated the field scouting charts so they now link to pages within the 2018 version of the Insect Field Guide

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

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!

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!

Previous Posts

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

Abundant parasitoids in canola – Week 10 
Alfalfa weevil – Week 6

Cabbage seedpod weevil – Week 12 
Cabbage root maggot – Week 11 
Cereal aphid manager (CAM) – Week 2
Cereal leaf beetle larvae request – Week 8
Crop protection guides – Week 2
Cutworms – Week 4

Diamondback moth – Week 7
Download the field guide – Week 10

Field heroes – Week 8
Flea beetles – Week 4

Monarch migration – Week 8

PMRA Pesticide Label Mobile App – Week 4

Scouting charts (canola and flax) – Week 3

Ticks and Lyme Disease – Week 4

Weather radar – Week 3
Wheat midge – Week 12

White grubs in fields – Week 8

Wind trajectories – Week 6
Wireworm distribution maps – Week 6

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

    

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!

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

    

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!

Insect of the Week – Darksided cutworm

It’s spring, so it’s cutworm season. This week’s insect is the darksided cutworm. Mature larvae are hairless, greyish with a prominent white stripe on either side just above their legs. It is a climbing cutworm with feeding occurring at night. They have a broad host range including cereals, canola, corn, flax, sunflower, vegetables berry and tree fruits.

Find out more about the darksided cutworm at the Insect of the Week page.  Other important species include dingy, army, redbacked and pale western cutworms (See Insect of the Week: 2017 – May 1, 8, 15 and 29).

Darksided cutworm
Photocredit John Gavloski, Manitoba Ministry of Agriculture

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

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

    

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!

Weekly Update – Scouting Charts (Canola and Flax)

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


For 2017, 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!

Weekly Update – Scouting Charts (Canola and Flax)

Field scouting is critical – it enables the identification of potential risks to crops.  Field crop 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.

For 2017, 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“.

Growers can access biological information about the pest and its natural enemies, the type of damage it causes, how to monitor, and what pest management strategies might apply to help protect yield and quality (Fig. 1).

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!

Figure 1. Example of Bertha armyworm pages from the above field guide: