Thursday, 9 May 2019

Cutworms (May 9, 2019; Wk 05)

Cutworms (Noctuidae) – A field guide is 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!  

Several species of cutworms can be present in fields (Refer to downloadable PDF below).  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. 

In 2018, the Insect of the Week featured two economically important species of cutworms and some of the important natural enemies that help regulate these pests:
Wk01 (May 07, 2018) - Glassy cutworm
Wk02 (May 14, 2018) - Darksided cutworm
Wk03 (21 May, 2018) - Ground beetles: cutworm natural enemies

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 “2019 Cutworm Reporting Tool” then view the live 2019 cutworm map which is updated daily.