Bean Leaf Beetle
Soybeans – A few reports of bean leaf beetle defoliation have come in. Remember that it takes considerable defoliation, probably over 40-50% before it really is a concern at this time of year unless you are growing seed beans or food grade beans where bean pod mottle virus might be a concern because of quality issues. See the fact sheet at http://ohioline.osu.edu/ent-fact/pdf/0023.pdf for more information.
Corn – Numerous reports were still coming in from northern Ohio on the Asiatic garden beetle grubs being found, almost all in first year corn following soybeans planted into sandy soils. As there are no rescue treatments available, the only decision is whether to replant if stand loss is significant. More importantly, this pest should be kept in mind next year, and hopefully we will gain some information on how best to handle it. Obviously, seed treatments do not appear to offer any control. However, growers in these areas who might have used a granule or liquid soil insecticide on their first year corn should contact us as to whether they felt they got control of this grub or still saw significant stand loss (send an email to hammond.5@osu.edu). These observations will go far in helping us determine how to best manage it.
Reports have come in of armyworm on corn in rye cover crops and black cutworm feeding on small corn. This is the time that corn should be scouted for both these early season pests. With cutworms, remember to scout even though seed treatments were probably used. Experience has indicated that the seed treatments do not adequately, manage cutworms (see the following fact sheet http://ohioline.osu.edu/ent-fact/pdf/0035.pdf for more information on black cutworms).
Alfalfa – As reported last week, this the time when potato leafhopper begins their build up, so alfalfa should be scouted for their presence. The potato leafhopper fact sheet is at http://ohioline.osu.edu/ent-fact/pdf/0033.pdf .
Source : osu.edu