Proper scouting and record keeping can help any superintendent save resources and be more precise with pesticide applications. In many instances, this could mean making targeted applications in specific locations rather than blanket sprays that might be unnecessary and costly.
A good example of this is with annual bluegrass weevil (ABW) applications. I’m getting reports from courses in Virginia that are already seeing ABW moving in the rough and heading toward fine turf areas. Seeing a few ABW might not be a concern now, but without proper sampling you won’t know the size of the population and how big of a problem you might have.
There are several reliable methods to sample for ABW. The first is a linear pitfall trap. A pitfall trap can usually be made in-house using a short piece of irrigation pipe with a narrow slit cut on the top leading to a collection bucket of some sort. Place the pipe in the ground perpendicular to the direction you think ABW are moving onto the course. The next, and perhaps most common method is a soap flush. A mixture of soap and water poured onto areas where you think ABW are present will irritate them and bring them to the surface for easy collection. When mowing starts to occur more frequently, simply examining grass clippings in the mower buckets can give a good idea of how many adults you have. Some courses are even using reconfigured hand-held leaf blowers to suck up adult weevils in a wide range of settings.
If you are not seeing ABW yet and you are in Maryland or states farther north in the region, it is probably just a bit early. But if this weather pattern holds, I’d start planning my sampling and control strategies now. If you’ve had ABW in the past, it’s only a matter of time before you see them.
Northeast Region Agronomists
Darin Bevard, senior director, Championship Agronomy – dbevard@usga.org
Elliott L. Dowling, senior consulting agronomist, Northeast Region – edowling@usga.org