USGA Regional Update
By Bob Vavrek, Senior Agronomist
May 17, 2010
Out of sight…out of mind. Addressing the daily annoyance of ant activity across tees and along putting surface perimeters during the hot weather of July and August is not a priority for most superintendents at a time when current concerns such as frost delays, sluggish recovery from winter damage, and a heavy crop of Poa annua seedheads take center stage. Nevertheless, the most effective way to limit nuisance ant activity later this season is to initiate a control program just as soon as mounds appear this spring.
Just to avoid confusion, this update discusses control strategies for the mild mannered turfgrass ants up North and not the notorious fire ants of the South.
Temperature dictates the growth rate of insect populations, so the recent stretch of unusually cool weather across the upper Midwest provides a little extra time to scout the golf course for the first signs of ant activity and take appropriate action. The queen ant and most of the colony will likely be located deep in soil and well beyond the reach of standard insect control measures if you postpone treatments until later this summer. Attempts to eliminate ant mounds across high-priority playing surfaces during August, with short residual insecticides, rarely achieves the desired effect, and probably does little more than temporarily set back the population of foraging worker ants for a few weeks.
The ideal ant control strategy would control the queen and thus eliminate the colony. Controlling the queen is a challenge, but you can increase your chances of success by understanding the habits and life cycle of the pest. Useful information regarding the biology and control strategies for nuisance ants in turf can be found on Dr. Harry Niemczyk’s web site:
The strategies recommended to control ant colonies utilize the extended residual effectiveness of materials such as clothianidin and thiomethoxam. For example, demonstrations at several golf courses in the upper Midwest indicate that the combination of clothianidin, and a synthetic pyrethroid, such as bifenthrin, can be particularly effective for controlling ants as well as grubs, billbugs and other insect pests of turf. A treatment applied to turf during spring when ant mounds are first observed will likely control first generation cutworms as well.
The shorter the turf, the more likely ant mounds are going to be a problem, so most courses will only need to address significant ant activity on greens, collars, approaches and tees. However, there is more to effective ant control than meets the eye. Most of the ant colony will be located just off the green, in the surrounds, even though the annoying mounds are seen on the collar and perimeter of the putting surface. Consequently, any treatment intended to control ants along the perimeter of the greens should include the first 20 feet of turf outside the collar, which, incidentally, is the same strategy employed for cutworm control.
No doubt, high populations of ants can become a pest of closely mowed golf turf, but they also serve an important role as beneficial scavengers and predators in the turfgrass ecosystem. Always employ sound pest management strategies that include scouting, mapping, and accurate identification; along with a thorough understanding of the target’s life cycle when developing a plan to control any pest.
Be tolerANT. Most courses will find that only a small percentage of the turf will need to be monitored for problems associated with mounds or turf thinning and that spot treatments will address all but the most significANT problems.
Source: Bob Vavrek, firstname.lastname@example.org or 262-797-8743