You Are Here: Management Updates 2008 Archive May 30, 2008

Date: May 30, 2008
Category: Insects
Subject: Annual Bluegrass (Hyperodes) Weevil

We have been collecting turf samples from several locations in the Northeast, ranging from Westchester County (NY) to the Hartford area (CT) and central Massachusetts. Plugs pulled this week indicate that annual bluegrass weevils (ABW) are appearing mostly as small and medium sized larvae right now. In the Hartford area they are mostly small larvae, while in the metropolitan area there were a few medium-sized larvae. If memory serves correctly, this is a few days "behind" last year's development, but the main point of the message is to let you know that the ABW are finally on the move. If we have more seasonable temperatures in the coming days, those of you in the metropolitan New York area can expect to see stressed turf as early as next week.

It is too late to treat for adults at this point. Those of you in the metropolitan area (or other areas where larvae have reached the medium size and have left the stem) should get some relief by applying trichlorfon (Dylox™) or indoxacarb (Provaunt™) or spinosad (Conserve™) if necessary. (Remember that the tolerance level is generally considered to be 30 to 80 larvae per square foot at this time of year.)

Also note that we often find large concentrations of tiny larvae in some of our samples, while other samples have no larvae. The distribution of larvae usually evens out a bit as they get a little larger, so take several samples to get a really good representation of what is really going on. In other words, don't panic just because you find a larva or two in a sample!!!

Submitted by: Dr. Pat Vittum

DISCLAIMER - As always, it is the responsibility of the applicator to verify the registration status of any pesticide BEFORE applying it. Different states have different regulations as well. The author and the University of Massachusetts are not liable for any consequences of any pesticide "recommendations". Mention of any trade name is not to be considered endorsement of a product.

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