You Are Here: Management Updates 2002 Archive September 5, 2002

Date: September 5, 2002
Category: Insects
Subject: Ants in Turf

ANTS seem to be providing the biggest headache for golf course superintendents right now. The turfgrass ant, Lasius neoniger, is the most common species we encounter in New England. I have received numerous reports of winged ants flying in large numbers over the past few days. I suspect that the restorative rains of last week may have triggered some of this activity.

The behavior we are seeing is normal. Adult males and females emerge in a synchronized manner (usually most of the ants fly within a few days of each other in any given location). Some of these "flights" are quite remarkable, with thousands of ants crawling to the tips of grass blades and taking wing. After they mate, females return to the turf and burrow into the soil. Apparently, they are choosing to burrow in places that are already weakened - seams where a cup was changed recently, ball marks, divots. And they are creating mounds in these weak spots that are causing considerable distress, at least aesthetically. In addition some superintendents are dealing with crows and other foraging creatures that are hunting the tasty little devils!

According to Dr. Dan Potter (University of Kentucky), the females will create a small protective burrow this fall, but most of them will not begin laying eggs until next spring. So the activity we are seeing now is a precursor to more activity next spring. Meanwhile there are still some workers "out and about", foraging and provisioning current colonies.

In many cases it may not make sense to "control" the ant activity since most of these ants will burrow in only once this fall, and then will pretty much stay put until next spring. Ant baits will work too slowly, in part because there will be relatively little foraging activity from the new females.

But you may get some "relief" by applying chlorpyrifos (Dursban) or one of the synthetic pyrethroids to the surface. Be sure that the formulation you use includes "ants" on the label. Water in very lightly (one or two passes of the irrigation head), and recognize that the application may not have any noticeable effect on the population.

Also remember that an insecticide application in September should be considered as a temporary (and inconsistent) approach at best. More rigorous attempts at reducing ant activity should begin next April or May, as soon as new mounds become apparent.

- Submitted by: Dr. Pat Vittum