Published on 08/28/02

Drought keeps turf pest at bay

By Sharon Omahen
University of Georgia

It's hard to think of any reason to celebrate over the state's drought conditions, but south Georgia golf course managers have one. Fewer mole crickets.

Mole crickets are small, light brown insects that live in, and cause extensive damage to, turf. They are commonly found throughout the southeastern coastal plain from Texas to North Carolina. Here in Georgia, they are only found below Macon in sandy soils of the state's coastal plain.

"They like sandy soils so they haven't moved into the northern portion of our state," said Will Hudson, a University of Georgia entomologist who researches this and many other of our state's insect pests. Hudson's laboratory is located in the heart of the coastal plain on the Tifton campus of the UGA College of Agricultural and Environmental Sciences.

Tunneling Across Fairways

Mole crickets burrow beneath the soil creating tunnels similar to those made by moles, but much smaller.

"Their tunnels can cause golf course managers a lot of grief," said Hudson. "Even the best golfer couldn't make a ball roll straight when mole crickets have burrowed tunnels across the green."

The size of tunnels can be used to indicate the age of the mole cricket population. As the mole cricket increases in size, so does the tunnel.

In addition to the damage caused by the tunnels, mole crickets damage turf by feeding on the plant roots, stems and leaves. But overall, mole cricket feeding is not considered as damaging on golf courses as their tunneling.

$20 Million in Annual Damage

It is estimated that mole crickets in commercial, recreational and residential turf cost Georgians $20 to $25 million a year in damaged grass and control expenses, said Hudson.

"Treatments can cost as much as $315 an acre, so just one hole of a golf course could cost between $600 and $800 to treat," he said. "It has been common for a high-end golf course to spend $1,000 a hole to control mole crickets and, even at that price, not get good control. New products have improved control considerably, but the cost is still high."

But over the last several years, Georgia's drought has drastically reduced the mole cricket population.

Mole crickets lay eggs in underground cells in the spring. The eggs hatch in three to six weeks, depending on the weather, and the nymphs feed and grow through the summer, and mature into adults in the fall.

Immatures Can't Stand the Heat

"May and June are the months when mole cricket eggs hatch, and the last few years it has been so dry and hot that the immature mole crickets haven't survived well," said Hudson. "There are still plenty of mole crickets around in golf courses and parks and managed turf areas, but the drought has definitely reduced their numbers. This is particularly true in nonirrigated areas like roadsides, pastures, and fields."

So if you're putt veers to the right a little, you can't blame the mole crickets. At least not this year.

Sharon Omahen is a news editor with the University of Georgia College of Agricultural and Environmental Sciences.