Field Crops
Lesser cornstalk borer, Elasmopalpus lignosellus, arrived in the IIL on a corn sample. It had bored in to the stem at the base of the plant. The oval jagged hole was at the base of the stalk just above the brace roots. Sanitation and clean plowing are the only listed controls that I found.
Thrips and Mite injury continue to arrive on various beans. Thrips leave not only the yellow spots but can cause stunting and leaf curl. Mites leave the "sand blasting" type damage and silk webbing. See PMG 016, pgs. 160 and 162 for soybeans. See PMG 018, pgs. 31 and 40 for garden beans.
The completed Corn Earworm Survey will be sent soon from the Distribution Center or you will receive it electronically. Now would be a good time to teach scouting methods for soybeans.
Vegetables
Remove all large stemmed weeds and stalks and stems of plants that are done producing. These plants can act as nursery and overwintering sites for stalk borers and European corn borers.
Ornamentals and Shade Trees
Now is a good time to check for early damage from late summer defoliators. Caterpillars like the orange striped oakworm, greenstriped mapleworm, fall webworm, and poplar tentmakers are just getting started and are now easy to control. Later this month they will be too big to spray and will have already caused their damage. Treat when caterpillars less then 1/2" are found.
Euonymus Scale, second generation, is active now and can be controlled with foliar sprays.
European Hornets (red an hairy thorax in contrast to the smooth thorax on the Cicada Killer) will become more active this month and will start chewing the bark off of small trees particularly lilac and virburnum but others as well. Look for patches of bark removed exposing the cambium.
LARGE Cicada Killer wasps are active now and are digging holes in soil and sand. They rarely sting and are considered beneficial.
Orangestriped oakworm have hatched in our area. The larva are still 1st instar and easily controlled. Only a few skeletonized leaves are evidence of a group of larvae that may have migrated 1-2 feet from where they originated. Can be removed by pruning.
Those fortunate enough to get a downpour will notice the absence of 2-spotted spider mites. We were monitoring a Buddlei that was heavily infested and showing over 80% of the plant with injured foliage. No mites could be found on a 5 leaf sample the day after a heavy rain. They will quickly return if the weather stays dry.
See my lab homepage: http://www.ento.vt.edu/Facilities/OnCampus/IDInfo.html