Canola Watch quiz: Diamondback moth

1. Diamondback moth larvae are green and range in size from tiny first instars little more than 1mm (these instars mine the inside of leaf tissue) to fourth instars 10-12mm (half an inch) long. Even the big ones are way smaller than a bertha armyworm. From the list below, pick the ONE characteristic that does NOT describe a diamondback moth larva. (Three DO describe the larve, one is wrong. Pick the wrong one.)

2. How many generations of diamondback moth can we have on the Prairies during a growing season?

3. What is the nominal threshold (which means it is based on expert assumptions but not specific research) for diamondback larvae at the critical flowering to pod stage?

4. Before spraying, read labels for all product options to check on pre-harvest intervals, application recommendations and weather effects. For example, some products can be applied to canola only once per season, others multiple times. As for weather, lambda-cyhalothrin (Matador, Silencer) for example, should be applied in the morning or evening to avoid the heat of the day. The Decis label says specifically, do not spray when temperature exceeds ____.