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The Insecticide Problem

by JOE TRAYNOR
California

The use of insecticides has increased greatly in the last 10 years and annually continues to do so. The beekeeper is caught in the middle of this upsurge in insecticide use and often is considered an unwelcome trespasser or at best a bothersome nuisance in mankind’s unyielding war on his eternal insect enemies.

Ironically, “Silent Spring,” the late Rachel Carlson’s eloquent plea against the indiscriminate use of insecticides, is likely the worst single event to happen to the beekeeping industry in the last decade. Although it is generally conceded that Miss Carlson overstated her case, her book served to awaken many people in government, as well as the general public, to the potential hazards of insecticides. The result was the passage of new insecticide legislation, with much of this directed at lowering the amount of residue permitted on feed and produce.

Unfortunately, the insecticides that leave what are considered dangerously high residues are often those insecticides that are not highly toxic to bees (e.g. DDT and some of the other hydrocarbons). Insecticides that leave little harmful residues are thus being used more widely today but these are often quite toxic to bees (e.g. Sevin and some organic phosphate compounds). These pesticides are often promoted as “safe” materials. The “safe” refers only to the low residue on the crop and has nothing to do with toxicity to honey bees, but this distinction is not always apparent to the farmer who buys the material. Increased use of the “low residue” or “high tolerance” pesticides has resulted in increased bee poisoning.

Today’s beekeeper is not alone in feeling that perhaps too much insecticide is being applied or that some applications are not necessary. “Modern agriculture in the U.S. could never have been developed to its present extent without the use of insecticides” is an oft-heard statement and it is undoubtedly true. However, to infer from this that “insecticide applications are the answer to all insect pest problems,” as some people do, would be of questionable soundness. Hodge Black, California Extension Farm Advisor, has said, “The first thing that ‘has to go’ is the idea with which too many people are possessed, namely ‘there isn’t a problem that can’t be sprayed for.’ ” Black also states, “Far too few farmers and pest control advisors have an understanding of the principles of pest control. The need for pest control is dictated by economics, but all too often by fright, frustration or pressure.”

This “fright, frustration or pressure” is evident in agricultural areas where the farmer has the specter of insect damage constantly before him. In farm magazines and newspapers, the farmer is confronted with large ads put out by pesticide companies depicting a giant worm taking a huge bite out of a leaf; he gets a notice from his agri-chemical distributor that aphids will be a problem this year, so he should get his order for spray material in early; while eating lunch and listening to the news report, he hears a commercial and the greatly magnified sound of a bollworm munching on a cotton boll; he hears his neighbor start up his spray rig; his foreman informs him that he has seen a few aphids moving in the west end of the north 40; on his way to town for a repair part, he sees numerous aircraft applying insecticides, and a billboard urges him to take revenge on those bugs that are taking money out of his pocket; in the evening paper he reads of an outbreak of armyworms 20 miles to the south, and while brushing his teeth before bed his wife informs him that she saw a cockroach in the bathtub that morning.

The farmer has seen how an outbreak of insect pests can devastate a field or orchard, so in this kind of atmosphere it is not difficult to see why he succumbs to the “better safe than sorry” philosophy prevalent in insect control today. Spray schedules put out by extension services and the pesticide companies are often followed religiously instead of being used as the guide they were intended for. Sprays are often applied as “insurance” with little or no knowledge of whether they are actually needed or whether the benefits derived will offset the cost involved.

Many good insecticide company entomologists and independent entomologists have been swept up in the zeal for “complete control” of harmful insects. Applications are often made on the basis of sweeps with an insect nest; when the count per sweep of a particular harmful insect reaches a certain level, the field is treated. The count before and after treatment is recorded and given to the farmer. Too often it is the insecticide representative who can show the biggest difference in pre-application and post-application count of a particular harmful insect that gets the farmer’s business (and the beekeeper that gets the business from the applicator).

According to entomologist Dr. Paul De Bach, a proponent of less insecticide use, “The average farmer has been thoroughly ‘sold’ by insecticide salesmen, extension literature and so-called economic entomologists. He has adopted the oft-repeated T-V brain-washing slogan ‘The only good bug is a dead bug.’ Now, obviously, this has to change, not because biological control workers think it is bad, but because it doesn’t work.”(1)

Biological control is not a new concept; it stresses that harmful insects can be held in check by natural predators and that spraying will upset this balance. Most advocates of biological control do not believe that pesticides have no place in insect control but that insecticides, preferably selective types, should be used only when absolutely necessary. Hodge Black says it this way: “We are gifted with some wonderful crop protection chemicals which, if used properly and wisely, can assist us in making maximum yields and maximum profits.”

There are many examples of how biological control has given excellent insect control at lower costs. A good case study is in the San Joaquin Valley of California. A few years back, Bill Kincaid, who farms almond orchards totalling 380 acres near Ripen, inadvertently omitted a pesticide spray from one of his orchards. Later he could tell no difference in insect control between the unsprayed orchard and those he had sprayed. He cautiously continued the no-spray program and soon noticed quantities of ”new” insects in his orchards which an expert identified as “good” bugs that fed on harmful pests. Kincaid then decided to spray only when he felt his crop to be in dire danger from insect pests. He has not sprayed any of his orchards for 3 years and has sold his spray rig. His yields have held up and he has had less insect problems than his neighbors who follow a diligent spray program.

Some observers of Kincaid’s experiments are giving his method serious consideration. Others have seen but will not believe until the “powers that be” tell them it is possible: Experiences such as Kincaid’s suggest that a re-appraisal of current insect control practices is in order on the part of many growers.

It is unlikely that all growers would be in a position to eliminate insecticide applications entirely but it is not unrealistic to believe that the number of applications could be materially reduced.

Why haven’t better insect control methods been put into effect? A major part of the answer is that the present insect control machinery has been built up to such Gargantuan extent that it is virtually impossible to shut it off or change its course. In the last 20 years the pesticide industry has burgeoned into a multi-million dollar business. On many farms insect control easily heads the list as the most expensive item in the farmer’s budget.

To assess the responsibility for the current state of insect control totally to the agri-chemical industry would be an oversimplification, and would not be fair to the many capable and dedicated people in the industry. From a humanitarian standpoint, insecticides can be credited with greatly reducing the incidence of malaria throughout the world. The fact that American agriculture is well ahead of the rest of the world is due in no small part to the fact that the U. S. chemical industry is the strongest in the world.

It is the business of the agri-chemical companies to develop and sell chemicals and, while some companies can be faulted for exploiting the farmer’s natural fear of crop loss to insects, such tactics are certainly above board. To expect companies producing nonselective insecticides to play up biological control would be akin to expecting the oil companies to develop an electric car, or the beekeeping industry to distribute brochures on the benefits of sugar. Some chemical companies use intelligently written ads for promotion; however, many ads appeal to the emotions rather than the intelligence – a charge that has been leveled at “native fanatics” who would eliminate spraying altogether.

To say that insecticide representatives that call on the farmer and check his fields are more interested in selling pesticides than in the farmer getting long-lasting insect control would not only be false but illogical since the farmer will take his business where he can get the best insect control at the lowest cost. Further, independent entomologists not associated with these companies frequently make the same general recommendations. The problem is that there are not enough options open to the farmer.

The farmer can’t go into town and buy some biological control and apply it to his field. Biological control or integrated control (the integration of chemical and biological methods) requires more technical knowledge and skill and holds more pitfalls for untrained people than does complete reliance on chemical methods. The independent entomologist or farmer who advocates a curtailment in spraying must have complete confidence in his judgment. A mistake in the form of an outbreak of insects could long be remembered and could have a damaging effect on his reputation.

It is understandable that many good entomologists and farmers adopt the “better safe than sorry” philosophy; besides, everyone else is doing it. Farmers have been conditioned to fear attack by insect pests, an understandable and healthy fear, so when they feel threatened by insects, they want a quick solution. A mistake in the form of a pesticide application that is not needed is considered a “small mistake” since it is not glaringly evident and since field checks will show that the levels of harmful insects have been suppressed. If more frequent subsequent applications are required to keep levels down then so be it; if an outbreak of mites or other pests occurs due to an insect imbalance, there is always (or almost always) another insecticide to knock them down. There can be no doubt that many such “small mistakes” occur in insect control today.

For the layman to mount an effective argument for the reduction in insecticide application is extremely difficult just as it would be difficult to argue with a doctor who prescribed a shot of penicillin for your child at the first sign of a cold. Should you protest, the doctor inquires over his glasses if you wish to take a chance on the child dying of pneumonia. The advocates of less insecticide use are consequently few and the noise made by them is comparatively little.

Outlook

There are signs that point to a retreat from current insecticide practices, however, there were similar signs 10 years ago and little has changed. Beekeepers should be encouraged though that excellent efforts are being made by University and Government researchers to develop better methods of insect control, most of them compatible with honey bees. Such control methods include sterilization, sound waves, light, microbes, nematodes, viruses and sex attractants. Integrated and biological control are always being worked on.

There is much time, talent and money being spent, both in the chemical industry and at universities, in the developing and screening of insecticides. For instance it costs roughly $2 million to develop an insecticide, and for every one developed 100 or more are screened out. These efforts would be better spent on control methods that would be of longer lasting benefit to agriculture.

There is a growing disenchantment with current insect control practices among some farmers. A number of grape growers in the San Joaquin Valley have donated a good deal of money in recent years to finance University research on integrated pest control for grapes.

One of the most encouraging signs is that an agri-chemical distributor has entered the field of biological control and gives advice and provides beneficial predator insects to interested farmers. If a distributor can enter the field of biological control, it is not inconceivable that agri-chemical companies could profitably provide integrated control services. Such a combination would be of help in providing challenging positions for entomology graduates who have been trained in biological control methods.

The idea that toxic chemicals are not the final answer in insect control is not a new one. De Bach quotes a 1958 article: “There may still be some people who think that chemicals will provide the answer to all pest-control problems, but not many amongst right-minded economic entomologists, and the thought was never shared by some.” Today, however, there is no strong evidence of a future downtrend in insecticide
use.

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1. Biological Control of Insects and Weeds. Paul De Bach, editor, Reinhold Publishing Co., New York. 1964 – recommended for beekeepers interested in biological control. Another excellent book is Pest Control … Biological, Physical and Selected Chemical Methods, Wendell Kilgore and Richard L. Doutt, Academic Press, New York-London, 1967.