You Are Here: Management Updates 2005 Archive May 26, 2005

Date: May 26, 2005
Category: Insects
Subject: Armyworms, Annual Bluegrass (Hyperodes) Weevil

Armyworms?
I have received two reports of armyworm moths in eastern Massachusetts. I have not personally confirmed these reports but at least one was identified by a very qualified individual! Frankly, I do not know what this means. Certainly the potential is there for a caterpillar outbreak in early to mid June, but the current weather pattern may make it difficult for caterpillars to survive and thrive. So don't panic yet - but keep your eyes open.

Annual bluegrass weevils
We have just looked at samples of annual bluegrass weevils from a golf course in Westchester County, NY. About 75% of the larvae in the samples are still first and second instars (REALLY small - now we are using magnifying glasses to find them!). The rest were small third instars, which is about medium-sized. They seem to be developing on schedule, so areas in southeastern New York, southwestern Connecticut, and northern New Jersey can expect to see some large larvae by the first full week of June (around 6 June). Damage probably will be most apparent the following week.

Golf courses in most of Massachusetts, Connecticut, and Rhode Island will be about a week behind so weevil damage probably will not be apparent until the second full week of June in most areas. Of course if you have south facing slopes that warm up a little quicker, damage will show up there sooner. Once you begin to see the tell-tale signs of wilt, you should consider whether you will need to protect those areas with a curative treatment. If you decide you do, use trichlorfon (Dylox™) - but only for spot treating the most heavily infested areas. Remember, Dylox™ now includes the annual bluegrass weevil on the federal label but not all states have approved the change yet.

Meanwhile the folks in northern New England are still in the waiting stage! I was near Concord, NH earlier this week and noticed several Forsythias were still showing a lot of yellow. We have had reports that further north (Bar Harbor, ME) the Forsythia are also just starting to show green in the leaf buds. Again that should be the perfect time to use a preventive material (like a pyrethroid or chlorpyrifos) in the areas where you have had damage in past years.

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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