The active chemical in Penncap has always been deadly to bees: Since a rash of Penncap-related bee kills in the 1970s, the pesticide's warning label has specifically directed applicators not to spray it on blooming fields where bees are foraging. But the pesticide can kill bees more insidiously, too.
Penncap capsules are about the same size as pollen. Bees flying into fields gather up the encapsulated chemical along with pollen and return to the hive. There, the pesticide can wait like a time-bomb, slowly leaking out and poisoning a colony up to a year after it has been deposited.
So when Theobald learned that his neighbor was about to spray with the pesticide, he was less than pleased. Still, there wasn't much he could do. In the agriculture business, beekeepers are unique in that their livestock grazes on land they neither own nor rent; they are squatters on the edge of an industry.
Typically, what a farmer gets in return for allowing his field to be foraged by honeybees is a free army of pollinators that spread crop seeds across acres of farmland. But many of Colorado's biggest and most important crops, such as corn and alfalfa, are pollinated by wind and don't require bees. As a result, beekeepers don't have much pull with many of the state's farmers.
Complicating matters even more is that aerial spraying is an inexact practice, and a lot can happen between the time the insecticide leaves the plane and when it reaches the ground. Wind drift is a common phenomenon. "I can't stop that spray on the last row of corn and keep it from going no more than six inches into the weeds next to the field," says Dan Tietmeyer, who flies for Crop Air Inc. in Eaton. "If I stop spraying too far from the edge of the field the farmer gets mad. And he's the one who's my client."
In Theobald's case, a plane sprayed Penncap-M on twelve fields near his hives. "Within a couple hours of that application bees started dying," Theobald says. "When it was over it was a fairly serious kill--10,000 to 15,000 bees in each of my 20 to 30 hives in the area."
Theobald filed a complaint with the state ag department, which regulates commercial pesticide applicators, claiming that the sprayer had violated Penncap's strict warning label. Two days later the state inspector showed up. He collected some dead bees, a few hive-top swabs and vegetation from the fields that had been sprayed, as well as control samples from adjacent fields for comparison purposes.
Three months later the ag department sent Theobald its conclusions. While their sampling had indeed turned up several positive identifications of methyl parathion--the active ingredient of Penncap-M--the inspectors said they couldn't be certain the actual spray at fault was Penncap-M and, if it was, they couldn't be certain the chemical had been misapplied. Maybe Theobald's bees flew to the wrong field: Who could know?
Six months later, in May 1995, Theobald got around to replying. "There may be other possible explanations for this bee kill," he agreed. "One: The methyl parathion in question was deposited by a UFO. Two: A marauding band of bee-mutilating Gypsies is at work in the west. Three: The bees themselves, cleverly disguised as farmers, flew many miles to the nearest supplier of methyl parathion, where they presented falsified credentials, purchased large quantities of the suspect pesticide, and returned to the bee yard, where they committed mass suicide."
A postmortem of Miles County's Sterling-area hives also found some evidence of methyl parathion. Despite both Theobald's and County's absolute certainty that their bees were done in by Penncap-M, however, the mystery is not solved that easily. There are huge gaps between what beekeepers claim they know from years of keeping bees and what researchers claim they know from their research.
For starters, even though the number of hives in Colorado plunged by a third last year, the honey business here is remarkably healthy, a fact that beekeepers are reluctant to concede but that statistics support. Despite the bee kills, Colorado's honey production barely dropped between 1995 and 1996. Producers also are getting more money for honey than ever before, although the 79 cents a pound averaged here is slightly below the price tag in other states.
Even the most basic assumptions about honey production can be grounds for dispute between beekeepers and researchers. For example, in its recent effort to determine the cause of the bee-kills, "the Department of Agriculture has taken us back to ground-zero," Theobald complains. "They won't even acknowledge that bees use corn for pollen. Corn is a rich source of pollen for bees, and anyone who knows anything about bees knows this. To say otherwise is like trying to tell a rancher with a problem that his cows don't graze on grass."