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(Thursday, Sept. 19, 2002 -- CropChoice news) --

Samuel Fromartz, Reuters, 09/18/02, via AgNet: WASHINGTON - Sweet corn is, according to this story, a summer tradition. Farmers sell bushels of the stuff to eager customers and they keep on selling it as long as worms don't poke out of the ears.

Jack Manix, an organic farmer at Walker Farm in Dummerston, in southeast Vermont, was quoted as saying, "At a farm stand, corn is your No. 1 crop." For organic farmers like Manix, though, corn has, the story says, been a particularly pesky crop -- worms seem to like it as much as humans do. What humans don't like is peeling open an ear of corn and finding a wiggling worm.

While organic farmers have lived with this problem for years, a new product has come on the market. Inspired by farm-folk wisdom and nurtured by technology, it was developed by a researcher at the University of Massachusetts. Its aim? To zap the worms organically before they damage the crop.

The story explains that when corn earworm moths migrate north, they lay their eggs on corn silk. The eggs hatch into caterpillars, then wiggle down the silk strands and, protected by thick husks, take up residence in the ears.

Conventional farmers spray their crop with chemical pesticides, often as many as five times, even if it means they can't go into their fields after application.

Until recently, organic farmers simply crossed their fingers or said a prayer that the pests wouldn't be too bad during the season, since they had to face customers at farmers markets.

Jim Crawford of New Morning Farm in Hustontown, PA, who sells in Washington D.C., was quoted as saying, "Some customers would be horrified to see a worm," while other customers would simply view the worms as tried-and-true organic -- evidence of a pesticide-free crop.

But if the infestation was chronic, many farmers would let the crop wither in the field, since the point was to offer customers an organic product as good or better than conventionally farmed produce.

Ruth Hazzard, in the Department of Entomology at the University of Massachusetts in Amherst, was quoted as saying, "It was a major problem."

Twelve years ago, she recalled, a New Jersey farmer related a story from an old timer, who said that farmers would place a drop of mineral oil on the thin strands of corn silk to suffocate the young worms before they migrated down into the ear.

Hazzard did some research on her own and found material to back up the folk wisdom, from the pre-World War II era before pesticides became prevalent. So over several years, with government and foundation grants, she developed a system to apply oil to the silk.

The story says that Hazzard switched to corn oil to meet organic standards and eventually added Bt, a commonly used soil bacterium that kills bugs when they eat it.

Students from U. Mass. as well as nearby Hampshire College developed a gun-like applicator, which can deposit a drop of the oily potion directly on the silk. It needs to be applied once on each ear, and takes 8-10 hours per acre.

They named the contraption the Zea-Later, a pun on the phrase "see ya later!" and Helicoverpa zea, the scientific name of corn earworm. When Manix tried out a prototype Hazzard provided in 1997, the field he tested it on had only a 5 percent earworm infestation vs. 75 percent in his untreated fields.

In subsequent studies, the improvement appears to be around 25 percent. In other words, farmers might get only a 50 percent infestation instead of 75 percent rate without the application.

Crawford, who has been using the system for two years at New Morning Farm in south central Pennsylvania, went many weeks with hardly a worm in sight -- until September.

The latest problem might have come from applying the oil too late, since there is a very narrow window during which it needs to be applied to the corn silk.

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