Farmers concerned about grasshoppers

Matanuska Valley farmers are fighting off swarms of grasshoppers this summer in what some call the worst infestation yet, a problem ranging from mere cosmetic damage to outright destruction.

Young seedling plants are hit hardest, while older plants are chewed around the edges which make them not as attractive for the market.

Ben Vanderweele, owner of the 100-acre Vanderweele Farms which supplies produce for Carrs, Fred Meyers and other outlets, said he has been able to match output with previous seasons, but the grasshoppers are truly a threat.

"Seems like they're out there by the zillions. Some of the potato plants are small and if they keep it up, eating at the leaves, there won't be anything left but stems," Vanderweele said.

It's hard to kill potatoes, yet some damage seems inevitable, he said. Carrots are likewise vulnerable to the voracious appetites of grasshoppers who zoom in on the seedlings and eat them up in no time.

Fred Pyrah, owner of the u-pick Pioneer Peak Farm, said he sees grasshoppers every year, but never has he seen them so thick.

"They've been mowing down the fields, and I fear for the vegetables," Pyrah said. "I spray around the perimeters but it doesn't seem to be working."

Pyrah said he used Malathion and Sevin mixed with molasses, which are both herbicides and highly expensive at $140 a gallon. "I don't spray anything on my vegetables. But even on the outside of the fields, there's no residual effect."

Leafy plants like broccoli, lettuce and cabbage seem to be favorites, while tomatoes and zucchini aren't high on the grasshopper list of foods, said Dr. Dennis Fielding, a researcher at the University of Alaska Fairbanks U.S. Department of Agriculture. Grasshoppers also attack oats and new-growing hay.

Fielding specializes in grasshoppers, and has studied the outbreak at Delta Junction and the Matanuska Valley. Those two areas are the primary places in the state that are seeing a proliferated grasshopper population, he said.

"Two years ago, Delta Junction and the Valley had a problem, but this year the problem seems to be worse," Fielding said. "It takes two years for eggs to hatch, so what you're seeing now are the offspring of those from 2000."

The main solution is to spray the perimeters of fields, he said, hitting the grasses and weeds that grow around a crop. That gets the grasshoppers before they spread across fields, but must be repeated again every few days, Fielding said.

Like Pyrah, Vanderweele said he does this, spraying a huge margin around his field, but insecticides get expensive, and he finds the process doesn't help that much.

Natural enemies also can attack the grasshopper, such as birds, certain species of fungus, parasitic flies, and diseases. So far, research hasn't led to an answer about how to manipulate a natural enemy to help keep the population down, Fielding said.

Farmers say they would like to see biological controls figured out before they have a horrific season in 2004.

The species found at Delta Junction and in the Valley are close relatives of the "locust" hoppers that tortured farmers in the midwest after the turn of the century. That species died out and is now considered extinct, Fielding said, probably due to habitat changes along creeks and drainages.

Hoppers like hot, dry weather, but not so hot that the grasses dry up. They probably do well in the Valley because of warmer recent summers, Fielding said.

Pyrah said he doubts that the grasshoppers follow a strict two-year cycle, even taking into account that that's how long it takes to hatch their eggs. In his 25 years of farming here, he said the pattern seems to be mostly in terms of warm weather.

"We've had a bad grasshopper problem three times in the past 25 years. If we get too many hot temperature days in a row, the grasshopper population goes up," Pyrah said. "Only in those years when we had hot temperatures has the infestation gotten bad."