David Owens, Extension Entomologist, owensd@udel.edu
Ticks
Before you get back into your trucks after looking at fields, take a moment to check pant legs for ticks. Ticks have remained active winter-long in states to our north. Last year I saw my first tick at the end of March.
Soil Pest Sampling for Field and Root Crops
With the soil warming nicely, now is a good time to scout for soil insect pests. There’s one method that is especially useful for wireworm and one for wireworm and white grub: baiting and compact soil sampling. With baiting, you want to bury about a cup of naked corn seed (Poncho or Cruiser free-seed) or corn seed mixed with naked small grain about 2-3 inches deep and cover with a piece of black or clear plastic. The black material will heat the soil up causing seed to germinate. The germinating seed is very attractive to wireworms. Come back to the spot in about 2 weeks and dig up the baits. One wireworm per location is enough to consider some sort of treatment. Wireworms are pretty susceptible to neonic seed treatment. You may see wireworms while digging the holes to place bait. If so, your job is done. Baiting is most effective in fields without cover crop. The second method is the compact soil sample method. Dig up a hole 8 x 8 x 6”. One wireworm or one white grub is considered justification for a treatment. You will want to take 5 to 10 samples per field. Sampling may miss low populations that can cause damage to high value root crops such as potato or sweet potato.