David Owens, Extension Entomologist; owensd@udel.edu
Sweet Corn
Corn earworm activity actually ticked up a fair bit at some sites on Monday. Traps are being checked today, but with the continued corn earworm activity in blacklight traps, I think it is best to stay on a 3-day spray schedule. Trap counts are as follows:
| Location | Blacklight Trap | Pheromone Trap |
| Dover | 8 | 14 |
| Wyoming | 13 | 74 |
| Magnolia | 28 | 22 |
| Milford | 16 | 23 |
| Harrington | 6 | 100 |
| Woodenhawk | 18 | 28 |
| Bridgeville | — | 12 |
| Concord | 10 | 6 |
| Georgetown | 0 | 10 |
| Laurel | 55 | 5 |
| Delmar | 18 | |
| Milton | 24 |
Brassicas
Beet armyworm activity continues to be very high. It can look similar to imported cabbageworm, but will be smooth and two-toned. Often the top side of the caterpillar is a different color tone than the underside and side. Beet armyworm is very damaging as the caterpillar seeks the growing point and eats it instead of working on the whorl leaves like imported cabbageworm. There are some populations in the area that may have diamide resistance as well.
Tomatoes
Stink bugs are very active in tomatoes at Georgetown. Worm pressure continues from corn earworm and from beet armyworm. The best stink bug materials are Hero, Bifenthrin, Lannate, and Venom or Scorpion. Pyrethroids alone should not be relied on to protect from any of the worm pests, and last year we had loopers get into the tomatoes and actually had worse damage in pyrethroid-treated plots.
Spinach
Continue scouting for webworms and beet armyworm. Pyrethroids should not be used to control either species.
Lima Beans
Continue scouting for soybean looper, corn earworm, and stink bugs. Loopers are more difficult to control, so be sure to scout and identify the worm complex before selecting a material.