May 13 Quiz — Weed control

1. You may need pre-seed glyphosate rates up to 540 gae to control large winter annual cleavers like the ones shown here. How long should you wait after spraying these weeds before seeding canola?

2. If herbicide is applied more than __________ hours BEFORE a frost event, efficacy on living plants will be retained and the plant will continue to decline when temperatures warm up again.

3. To achieve good herbicide efficacy after a frost, spraying can resume after one but ideally two days of warm sunny conditions and one but ideally two nights with lows of ____ or higher.