Tag: True armyworm

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.

Winter Update – 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:




Update from the field….

Many prairie growers have a cutworm or armyworm story of woe but this time around growers on Vancouver Island near Port Alberni contended with an unusual pest – True armyworm (Mythimna unipuncta) in high densities were eating up hay fields and pasture!  Thanks to Tracy Hueppelsheuser with the BC Ministry of Agriculture who shared this CTV news clip.


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