Pea leaf weevil – latest Alberta survey and map available
LETHBRIDGE, AB. — Initial findings from the 2021 pea leaf weevil (PWL) survey maps for Alberta are out and showing lower numbers than what has been seen in previous years. This could be due to the dryer growing conditions, especially in Southern Alberta.
The survey, completed in late May and early June of 2021, was based on damage ratings in 225 fields within 58 municipalities.
In each field, the total number of feeding notches per plant are counted on 10 plants in 5 locations near the field margin. The damage rating for a particular field is the average number of notches per plant.
Although this survey concentrates on damage done by the adult, yield losses are caused by the larval damage to the nitrogen fixing root nodules.