Bertha armyworm monitoring (July 11, 2019; Wk 14)

Bertha armyworm (Lepidoptera: Mamestra configurata) - Early instar bertha armyworm are predicted to begin appearing across the prairies.  A model run for Saskatoon SK indicates that the hatch should be complete (Fig.1) and that BAW should be in the early instar (Fig. 2).

Figure 1.  Predicted status of bertha armyworm (Mamestra configurata) populations as of July 8, 2019.

Figure 2. Predicted percent of bertha armyworm (Mamestra configurata)  populations at LARVAL STAGE across the Canadian prairies as of July 8 2019. 

Important - Watch your provincial monitoring networks who are weekly recording cumulative pheromone-baited traps in Alberta, Saskatchewan, and Manitoba (pg 8).

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 "Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide" which is a free downloadable document as both an English-enhanced or French-enhanced version.

Refer to the PPMN Bertha armyworm monitoring protocol for help when performing in-field scouting.  Use the images below (Fig. 3) to help identify egg masses and the economically important larvae in canola.

Figure 3. Stages of bertha armyworm from egg (A), larva (B), pupa (C) to adult (D).
Photos: J. Williams (Agriculture and Agri-Food Canada)

Now is the time to do in-field scouting for this insect pest.  Review the Insect of the Week which features bertha armyworm and its doppelganger, the clover cutworm!