Predicted bertha armyworm development (Jun 07, 2018; Wk 05)

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. 

Though cooler temperatures have slowed BAW development, moths are predicted to emerge 10 days ahead of average (Table 1). Pupal development is approximately 82% (Fig. 1).  Model output predicts that emergence may begin as early as June 9th.

Table 1. Projected dates for BAW adult emergence for June 4, 2018 (projected to June 30, 2018).

Figure 1.  Predicted bertha armyworm pupal development (as of June 3, 2018).

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.