You Are Here: Management Updates 2003 Archive September 4, 2003

Date: September 4, 2003
Category: Insects
Subject: Annual Blugrass (Hyperodes) Weevil, White Grubs, Chinchbugs, Billbugs

Annual bluegrass weevils
I am still getting phone calls about the annual bluegrass weevil. Superintendents are still reporting the presence of larvae and pupae, with larvae still feeding in the crowns of suitable sites (anything shorter than rough!). The good news is that any adults that emerge now will not be starting a new generation. (Actually a few of the stupid ones might try to lay a few eggs, but the resulting larvae will not survive the winter. I figure such behavior on the part of the adults is "good for the gene pool".)

So there should be little or no additional damage from the insect. As cooler temperatures dominate September, the turf should begin to recover quite quickly. But do whatever you need to remember where the activity was this year, and be prepared to deal with it (in other words, put out a preventive
application) next spring.

White grubs
We received a turf sample from a golf course in central Vermont last week that had several second instar (middle-sized) Japanese beetle larvae in it. I was a bit surprised because I had been assuming the grubs would be running a little behind schedule this year, but at least at that site, they were right "on time".

On the other hand, we were digging a field plot in Waltham (just west of Boston) yesterday and found TINY grubs of oriental beetles and asiatic garden beetles. These little guys had hatched within the previous day or two. The European chafer grubs we found were all second instars. So all three species are running a couple weeks behind "normal" in terms of development. That was more what I had been expecting, since the spring was so wet and cool, and there were several stretches of cool wet weather during the summer as well.

So for turf managers - expect to find anything and everything. Nothing will surprise me this year. Some areas will apparently be close to "normal" while others will be running a little behind schedule.

As far as I am concerned, it is too late to apply imidacloprid (Merit) to control any grub problems, even though things are running a little late. Your best bet, at this point, is to use a curative product. In some states (but NOT New York!), bendiocarb (Turcam) remains an option for this year, and of course trichlorfon (Dylox) is normally an excellent quick hitter. (Again note that the readers in Maine do not have access to Dylox.)

As a reminder as you are looking for grubs, they may be in different places this year. Because there has been so much soil moisture (and some areas have been notably wetter than normal), the beetles may have opted to lay eggs in higher and drier sites.

Chinchbugs and billbugs
We received very few calls on either insect this year. I am assuming activity was indeed much lower than we saw in 2001 and 2002, primarily because the damage is more apparent in drought conditions. With all the rain we had in most parts of southern New England, the turf never really went into the noticeable summer cormancy, and while chinchbugs and billbugs undoubtedly were present, their activity was masked by the overall favorable growing conditions.

- Submitted by: Dr. Pat Vittum