You Are Here: Management Updates 2008 Archive June 25, 2008

Date: June 25, 2008
Category: Insects
Subject: Armyworms, White Grubs, Acelepryn™ Insecticide, Annual Bluegrass (Hyperodes) Weevil

Armyworms
The turf manager in eastern Massachusetts who suspected armyworm activity sent me some specimens and I was able to confirm that the caterpillars were indeed armyworms (Pseudaletia unipuncta). In addition, I received information from Indiana and Ohio that indicated turf managers in both of those states are reporting outbreaks of armyworms in some areas. So it appears that the potential exists for armyworm outbreaks throughout New England this summer. Check your turf areas now to see whether there is any armyworm activity. The earlier you diagnose a problem, the better your chances of achieving some level of control if that turns out to be necessary. See the update from 23 June for identification and management hints.

I failed to include indoxacarb (Provaunt™) as a treatment option in the earlier update. Provaunt normally™ is very effective against many kinds of caterpillars, including armyworms.

White grubs
Oriental beetles, European chafers, and asiatic garden beetles are all emerging now as adults. Japanese beetles won't be far behind (and in fact are probably already flying in some parts of New England). If you plan to use a neonicotinoid (e.g., imidacloprid, chlothianidin, or thiamethoxam), you should try to make the application during the month of July if at all possible.

Acelepryn
We just received word that Acelepryn™ (the new product from DuPont, chlorantraniliprole) has been registered in Connecticut. So now four of the six New England states have registered the product. (The other states where it has been approved so far are New Hampshire, Maine, and Vermont.) Registration is expected in Rhode Island and Massachusetts sometime this summer.

Annual bluegrass weevils
Based on conversations I have had with several golf course superintendents in the last couple days, the first generation of annual bluegrass weevils is rapidly winding down. One superintendent in Westchester County (NY) reported that most of the insects were still larvae or pupae on Monday, but when he went to check again this morning, there were new black adults moving very actively (and in large numbers) on the greens and fairways.

So ... be watching for changes in weevil development. Once you see large numbers of adults on the surface, you might want to consider treating those areas with a pyrethroid (especially if you do not have a history of repeated pyrethroid use) or chlorpyrifos (Dursban™). For those of you in northern New England, you may still be seeing mostly larvae. If that is the case and the damage is excessive, you may get some relief by making a curative application of trichlorfon (Dylox™), indoxacarb (Provaunt™), or spinosad (Conserve™). (Note that most of our field trials that tested Conserve™ were applied earlier in the life cycle, targeting small larvae, and we don't know how effect the product will be against large larvae.)

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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