cutworm moths on a round screen with muddy background
Trapping 50+ moths…in just 3 days… and it’s only May…is…concerning!

Peridroma saucia is common in Oregon. But for the past three years, we are detecting them at much higher-than-normal levels in early spring.

The graph below shows pheromone trap counts (# of adult moths per day) in recent years vs. a long term average. Please note that all data points before May 10th are NOT regional averages. They represent only the Corvallis location. These 5 single-location data points are filled with a dot pattern (hard to see, sorry). However, in 2020, the true regional average (peach diamonds) remained higher than normal until June 1st.

graph of variegated cutworm counts 1999 to 2022 in Willamette Valley, OR

What does this mean?

Well, this species is known to overwinter (mostly as larvae > pupae > adults) in Oregon. Since there are 2+ overlapping generations, this first peak could mean a higher abundance throughout the season.

Variegated cutworm larvae feed on many hosts. They are well known as a pest of peppermint but feeding has been documented on tomatoes, beets, alfalfa, grapes, ornamentals, and various vegetables. Scout now for eggs – they are laid in clusters on various landscape plants, weeds, even twigs and fence posts! If temperatures remain suitable, larvae could be evident by mid-May.

NOTE: It’s kind of odd/cool that this is the first species to report on this year, because my new boss, Len Coop, did his dissertation on variegated cutworm 35 years ago and it is still one of the best resources around! Thanks, Dr. Coop!

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