Sweet Corn
European corn borer (ECB) adults continue to be very low, and no map will appear in this edition.
Fall armyworm (FAW) larval infestations have declined to fairly low levels. Infestations generally are in the single digits to below 20%, but FAW could increase dramatically with the arrival of storms, resulting in significant injury to whorl and even seedling stage corn. Injury from newly hatched larvae shows up as “window panes” or areas where leaf tissue has been eaten down the the lower epidermis. This injury leads down into the whorl. As larvae gain size, they begin to consume leaf tissue in its’ entirety, creating ragged holes and lots of droppings. FAW can be tough to manage because it is resistant to synthetic pyrethroid insecticides (IRAC 3A) and because larvae are often covered by their own droppings, making contact with the insecticide more difficult. Treat when 12% or more plants exhibit FAW injury alone, or in combination with ECB injury.
Corn earworm (CEW) moth captures increased through late last week, and then declined in the past 4 nights due to cooler temperatures. This decline may be temporary, as we get into warmer weather late this week and into the weekend. The current population poses a significant risk to silking corn. Catches remain somewhat variable (see map at left), with green areas on this map representing a 3-day spray schedule. For further information on CEW activity, see pheromone trap information below.
The highest nightly trap catches of CEW in black light traps for the week ending 9/02/20 are as follows:
Downer 14 | Farmingdale 6 | Medford 4 |
Elm 9 | Haackettstown 6 | New Egypt 4 |
Green Creek 9 | Georgetown 5 | Princeton 4 |
Bellemeade 7 | Sergeantsville 5 | Tabernacle 4 |