David Owens, Extension Entomologist, owensd@udel.edu
Asparagus
Now that asparagus is up, be sure to scout for asparagus beetle and beetle eggs. Eggs are laid on the stems and look like small dark cylinders sticking out of the stem at 90 degrees. Scouting recommendations from Minnesota suggest to sample 20 plants in each of 5 locations. Thresholds are 2% of spears with eggs, 5-10% of plants with adults, and 50 – 75% of plants with larvae. Insecticide options, should they be necessary, include Lannate, Sevin XLR Plus, Malathion, and Permethrin.
Seedcorn Maggot
Seedcorn maggot adults are actively laying eggs in soil right now. Any recent organic matter incorporation, such as manure or tilled in cover crop is at high risk for maggot injury. Seed treatments containing a neonicotinoid (thiamethoxam, imidacloprid, or clothianidin) or Lorsban (chlorpyrifos) are highly recommended. There are no rescue options for SCM. In about 2-3 weeks, maggots will be pupating, and the risk lessens somewhat.
Spider Mite Fact Sheet
We have released a very detailed, in depth fact sheet on two spotted spider mite. It should be applicable to most crops grown in our area, both field and vegetable.