David Owens, Extension Entomologist, owensd@udel.edu
Cole Crops
Continue scouting and rotating chemistries for worm management. Cabbage is begging to form heads, during this stage the threshold goes down to 5% infested plants. Plants are also getting some size to them making coverage essential. Coverage can be improved by using drop nozzles with side-oriented nozzles and using adjuvants to help the droplet adhere to and spread out on the waxy leaf. If you are growing cauliflower, you may want to treat before tying leaves over the heads to prevent tying worms in with the developing head. Some university Extension personnel recommend a 1-5% threshold for cross striped worms because they can be extremely damaging to the plant where the egg mass was laid.