Thursday, 2 June 2016

Weekly Update (June 1, 2016; Wk 05) - Flea beetles

Reminder - Flea Beetles (Chrysomelidae: Phyllotreta species) – Remember, the Action Threshold for flea beetles on canola is 25% of cotyledon leaf area consumed.  Shot-hole feeding is the traditional damage in seedling canola but watch the growing point and stems of seedlings.

Estimating flea beetle feeding damage can be challenging.  Using a visual guide to estimate damage can be helpful.  Canola Watch circulated this article but also use the images (copied below for reference) produced by Dr. J. Soroka (AAFC-Saskatoon)  - take  them scouting!

Figure 1. Canola cotyledons with various percentages of leaf area consume owing to flea beetle feeding damage (Photo: Soroka & Underwood, AAFC-Saskatoon).

Figure 2.  Percent leaf area consumed by flea beetles feeding on canola seedlings (Photo: Soroka & Underwood, AAFC-Saskatoon).

Refer to the flea beetle page from the new "Field Crop and Forage Pests and their Natural Enemies in Western Canada: Identification and management field guide" as an English-enhanced or French-enhanced version.

Also refer to the previous Flea beetle post on the Blog.