Predicted bertha armyworm development (May 31, 2018; Wk 04)

Bertha armyworm (Lepidoptera: Mamestra configurata) - The BAW model is predicting that pupae are developing rapidly in the soil and that development is well ahead of average (Fig. 1).  Development is expected to be 5 - 6 days faster than average. 

Figure 1.  Predicted bertha armyworm pupal development (as of May 30, 2018).

Pupal development is approximately 72% (long term average is 47%). Model output predicts that emergence may begin as early as June 6, 2018 (Table 1).

Table 1.  Projected dates for bertha armyworm adult emergence as of May 28, 2018 and projecting to June 30, 2018.

Reminder - Review the 2017 bertha armyworm distribution map for the Canadian prairies which reports cumulative pheromone trap counts intercepting male moths during the 2017 growing season.

Biological and monitoring information related to bertha armyworm in field crops is posted by the provinces of Manitoba, Saskatchewan, Alberta and the Prairie Pest Monitoring Network.  Also refer to the bertha armyworm pages within the new "Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide" - both English-enhanced or French-enhanced versions are available.