Cutworms

Reminder – Cutworm scouting spans April to late June across the Canadian prairies!

This past week in Manitoba, Dr. John Gavloski reported sporadic cutworm infestations this spring. At least one canola field was reseeded and sunflower fields were treated with insecticides. Darksided and redbacked cutworms were observed in damaged sunflower fields. Significant cutworm issues have also been reported in Alberta.

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 either very early or late in the day when some cutworm species (or climbing cutworms) move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of symptomatic plants and also any healthy plants immediately adjacent to missing rows or wilting or clipped plants.  Some cutworms feed by remaining just below the soil surface, clipping then pulling the plant below as they munch away! If the plant is well-established (e.g., perennial grass or legume), check within the crown plus in the adjacent soil.  The culprits could be cutworms, wireworms, or more!

Important: Several species of cutworms (Lepidoptera: Noctuidae) can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  A field guide is available to help growers scout and manage the various species of cutworms that can appear in field crops grown on the Canadian prairies.  Cutworm Pest of Crops is available free in either English or French! Download a searchable PDF copy to access helpful diagnostic photos plus a table showing which larvae are active at different points in the growing season!

Other vital resources to scout and manage cutworms include:
● For anyone on the Canadian prairies, Manitoba Agriculture’s Cutworms in Field Crops fact sheet includes action and economic thresholds for cutworms in several crops, important biological information, and great cutworm photos to support in-field scouting.
● For Albertans….. If you find cutworms, please consider using the Alberta Insect Pest Monitoring Network’s “2024 Cutworm Reporting Tool” then view the live 2024 cutworm map updated daily. Review the live map to see where cutworms are appearing then prioritize in-field scouting accordingly.
● Cutworms were featured as 2024’s first Insect of the Week.

Cutworms

Reminder – Cutworm scouting spans April to late June across the Canadian prairies!

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 either very early or late in the day when some cutworm species (or climbing cutworms) move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of symptomatic plants and also any healthy plants immediately adjacent to missing rows or wilting or clipped plants.  Some cutworms feed by remaining just below the soil surface, clipping then pulling the plant below as they munch away! If the plant is well-established (e.g., perennial grass or legume), check within the crown plus in the adjacent soil.  The culprits could be cutworms, wireworms, or more!

Important: Several species of cutworms (Lepidoptera: Noctuidae) can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  A field guide is available to help growers scout and manage the various species of cutworms that can appear in field crops grown on the Canadian prairies.  Cutworm Pest of Crops is available free in either English or French! Download a searchable PDF copy to access helpful diagnostic photos plus a table showing which larvae are active at different points in the growing season!

Other vital resources to scout and manage cutworms include:
● For anyone on the Canadian prairies, Manitoba Agriculture’s Cutworms in Field Crops fact sheet includes action and economic thresholds for cutworms in several crops, important biological information, and great cutworm photos to support in-field scouting.
● For Albertans….. If you find cutworms, please consider using the Alberta Insect Pest Monitoring Network’s “2024 Cutworm Reporting Tool” then view the live 2024 cutworm map updated daily. Review the live map to see where cutworms are appearing then prioritize in-field scouting accordingly.
● Cutworms were featured as 2024’s first Insect of the Week.

Cutworms

Reminder – Cutworm scouting spans April to late June across the Canadian prairies!

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 either very early or late in the day when some cutworm species (or climbing cutworms) move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of symptomatic plants and also any healthy plants immediately adjacent to missing rows or wilting or clipped plants.  Some cutworms feed by remaining just below the soil surface, clipping then pulling the plant below as they munch away! If the plant is well-established (e.g., perennial grass or legume), check within the crown plus in the adjacent soil.  The culprits could be cutworms, wireworms, or more!

Important: Several species of cutworms (Lepidoptera: Noctuidae) can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  A field guide is available to help growers scout and manage the various species of cutworms that can appear in field crops grown on the Canadian prairies.  Cutworm Pest of Crops is available free in either English or French! Download a searchable PDF copy to access helpful diagnostic photos plus a table showing which larvae are active at different points in the growing season!

Other vital resources to scout and manage cutworms include:
● For anyone on the Canadian prairies, Manitoba Agriculture’s Cutworms in Field Crops fact sheet includes action and economic thresholds for cutworms in several crops, important biological information, and great cutworm photos to support in-field scouting.
● For Albertans….. If you find cutworms, please consider using the Alberta Insect Pest Monitoring Network’s “2024 Cutworm Reporting Tool” then view the live 2024 cutworm map updated daily. Review the live map to see where cutworms are appearing then prioritize in-field scouting accordingly.
● Cutworms were featured as 2024’s first Insect of the Week.

Cutworms

Cutworm scouting spans April to late June across the Canadian prairies!

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 either very early or late in the day when some cutworm species (or climbing cutworms) move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of symptomatic plants and also any healthy plants immediately adjacent to missing rows or wilting or clipped plants.  Some cutworms feed by remaining just below the soil surface, clipping then pulling the plant below as they munch away! If the plant is well-established (e.g., perennial grass or legume), check within the crown plus in the adjacent soil.  The culprits could be cutworms, wireworms, or more!

Important: Several species of cutworms (Lepidoptera: Noctuidae) can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  A field guide is available to help growers scout and manage the various species of cutworms that can appear in field crops grown on the Canadian prairies.  Cutworm Pest of Crops is available free in either English or French! Download a searchable PDF copy to access helpful diagnostic photos plus a table showing which larvae are active at different points in the growing season!

Other vital resources to scout and manage cutworms include:
● For anyone on the Canadian prairies, Manitoba Agriculture’s Cutworms in Field Crops fact sheet includes action and economic thresholds for cutworms in several crops, important biological information, and great cutworm photos to support in-field scouting.
● For Albertans….. If you find cutworms, please consider using the Alberta Insect Pest Monitoring Network’s “2024 Cutworm Reporting Tool” then view the live 2024 cutworm map updated daily. Review the live map to see where cutworms are appearing then prioritize in-field scouting accordingly.
● Cutworms were featured as 2024’s first Insect of the Week.

Cutworms

Cutworm scouting spans April to late June across the Canadian prairies! 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 either very early or late in the day when some cutworm species (or climbing cutworms) move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of symptomatic plants and also any healthy plants immediately adjacent to missing rows or wilting or clipped plants.  Some cutworms feed by remaining just below the soil surface, clipping then pulling the plant below as they munch away! If the plant is well-established (e.g., perennial grass or legume), check within the crown plus in the adjacent soil.  The culprits could be cutworms, wireworms, or more!

Important: Several species of cutworms (Lepidoptera: Noctuidae) can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  A field guide is available to help growers scout and manage the various species of cutworms that can appear in field crops grown on the Canadian prairies.  Cutworm Pest of Crops is available free in either English or French! Download a searchable PDF copy to access helpful diagnostic photos plus a table showing which larvae are active at different points in the growing season!

Other vital resources to scout and manage cutworms include:

For anyone on the Canadian prairies, Manitoba Agriculture’s Cutworms in Field Crops fact sheet includes action and economic thresholds for cutworms in several crops, important biological information, and great cutworm photos to support in-field scouting.

For Albertans….. If you find cutworms, please consider using the Alberta Insect Pest Monitoring Network’s “2024 Cutworm Reporting Tool” then view the live 2024 cutworm map updated daily. Review the live map to see where cutworms are appearing then prioritize in-field scouting accordingly.

Cutworms were featured as 2024’s first Insect of the Week.

Cutworms

Cutworm scouting spans April to late June across the Canadian prairies! 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 either very early or late in the day when some cutworm species (or climbing cutworms) move above-ground to feed.  Start to dig below the soil surface (1-5 cm deep) near the base of symptomatic plants and also any healthy plants immediately adjacent to missing rows or wilting or clipped plants.  Some cutworms feed by remaining just below the soil surface, clipping then pulling the plant below as they munch away! If the plant is well-established (e.g., perennial grass or legume), check within the crown in addition to the adjacent soil.  The culprits could be cutworms, wireworms, or more!

Important: Several species of cutworms (Lepidoptera: Noctuidae) can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  A field guide is available to help growers scout and manage the various species of cutworms that can appear in field crops grown on the Canadian prairies.  Cutworm Pest of Crops is available free in either English or French! Download a searchable PDF copy to access helpful diagnostic photos plus a table showing which larvae are active at different points in the growing season!

Other vital resources to scout and manage cutworms include:

For anyone on the Canadian prairies, Manitoba Agriculture and Rural Development’s Cutworms in Field Crops fact sheet includes action and economic thresholds for cutworms in several crops, important biological information, and great cutworm photos to support in-field scouting.

For Albertans….. If you find cutworms, please consider using the Alberta Insect Pest Monitoring Network’s “2022 Cutworm Reporting Tool” then view the live 2022 cutworm map updated daily. Review the live map to see where cutworms are appearing then prioritize in-field scouting accordingly.

Cutworms were featured as 2021’s first Insect of the Week. Follow the links to access IOTW’s descriptions of armydarksideddingyglassypale western and redbacked cutworms.

● The Prairie Pest Monitoring Network has cutworm biology, plant host range, and monitoring information available.

● The Canola Council of Canada’s Canola Encyclopedia also has cutworm information posted.

Cutworms

‘Tis the season…. to scout for cutworms! 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, cutworms, or more!

Important: Several species of cutworms (Lepidoptera: Noctuidae) can be present in fields.  They range in colour from shiny opaque, to tan, to brownish-red with chevron patterning.  A field guide is available to help growers scout and manage the various species of cutworms that can appear in field crops grown on the Canadian prairies.  Cutworm Pest of Crops is available free in either English or French! Download a searchable PDF copy that includes great photos plus a table showing which larvae are active at different points in the growing season!

Other vital resources to scout and manage cutworms include:

For anyone on the Canadian prairies, Manitoba Agriculture and Rural Development’s Cutworms in Field Crops fact sheet includes action and economic thresholds for cutworms in several crops, important biological information, and great cutworm photos to support in-field scouting.

For Albertans….. If you find cutworms, please consider using the Alberta Insect Pest Monitoring Network’s “2021 Cutworm Reporting Tool” then view the live 2021 cutworm map which is updated daily. Review the live map to see where cutworms are appearing then prioritize in-field scouting accordingly.

Cutworms were featured as 2021’s first Insect of the Week. Follow the links to access IOTW’s descriptions of armydarksideddingyglassypale western and redbacked cutworms.

● The Prairie Pest Monitoring Network has cutworm biology, plant host range, and monitoring information available.

● The Canola Council of Canada’s Canola Encyclopedia also has cutworm information posted.

Insect of the Week – 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.