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Pesticides and the Beekeeper

Bee Culture – November, 1979

by JOE TRAYNOR
Bakersfield, CA

TRUE-FALSE TEST:

  1. More insecticides are applied than are actually needed. T__ F__
  2. People that sell pesticides emphasize chemical control of insects more than biological control. T__ F__
  3. Most fieldmen that sell insecticides are more interested in sales figures than in economical insect control. T__ F__
  4. Most farmers unwittingly get pushed on an insecticide treadmill.* T__ F__
  5. Most insecticide applications are not actually needed. T__ F__

Answers: 1. T, 2. T, 3. F, 4. F, 5. ?

A growing anti-pesticide coalition in the U.S. would give “True” answers to all the above statements and would cite the last 3 as reasons for greatly increased governmental control of pesticides. Because insecticides represent a major, if not the major threat to beekeeping, some beekeepers are joining this coalition. This coalition would allow only those with no ties to insecticides (manufacture, distribution or sales) to recommend insecticide applications.

In all of this, the one that comes out the villain is the person who recommends insecticides and who also has ties with a manufacturer or distributor of insecticides. Is his black hat really deserved? A closer look at each of the above statements gives some clues:

1. More insecticides are applied than are actually needed. True. The amount of insecticide needed to control an insect is the amount necessary to prevent that insect from causing a dollar amount of crop damage greater than the cost of the insecticide application. Because the potential dollar loss from insect attack can be many times greater than the cost of an insecticide application, many insecticides are applied as “insurance” sprays. Beekeepers who apply chemicals to control foulbrood and wax moth can relate to the usefulness of, even the need for, insurance sprays.

2. People that sell pesticides emphasize chemical control of insects more than biological control. True. People that sell honey do not push sugar.

3. Most fieldmen that sell insecticides are more interested in sales figures than in economical insect control. False. and

4. Most farmers unwittingly get pushed on an insecticide treadmill. False. Because statements 1. and 2., above, are true, many in the anti-pesticide movement have jumped to the conclusion that 3. and 4. are also true. Although seemingly an easy jump, it is still one that requires looking before leaping.

The pesticide fieldman that has a farmer’s insecticide business usually also has his herbicide and fertilizer business because fieldmen usually represent a distributor that handles a complete line of agricultural chemicals. While it has not been too many years since insecticides represented over half of many farmer’s total ag chemical bill, the use of herbicides and harvest aids (defoliants and growth regulators) has increased to the point where insecticides must share the farmer’s ag chemical dollar with a much larger number of other chemicals. Although hard for some to accept, it is in the salesman’s best interest that the farmer gets the most economic insect control. Being more interested in insecticide sales figures than in economical insect control is a contradiction in terms. The farmer that does not receive economical insect control from his fieldman-salesman will be looking for another fieldman-salesman and, because ag chemical sales is a highly competitive business, he does not usually have to look far. The fieldman that pushes for higher insecticide sales at the expense of economic insect control does so at the risk of losing the farmer’s entire ag chemical business. It is a risk that few fieldmen take.

To believe that a farmer gets unwittingly pushed on an insecticide treadmill by high pressure insecticide salesmen is to assume a naivity on the part of the farmer that does not exist. The farmer that has no working knowledge of the rudiments of insect control is a rare breed, if he exists at all; the farmer that continually allows insecticide costs to eat up his profits does not stay in the farming business.

Cotton spraying in the San Joaquin Valley

Anti-insecticide advocates like to point to the recent history of cotton insect control in the San Joaquin valley of California as an example of how growers can be taken off a (salesmen induced) insecticide treadmill through the application of integrated pest management and eco-system management**. Every cotton growing area has it’s own insect problems and in the San Joaquin valley there are 2 major insect pests: the lygus bug, which destroys the cotton square (immature bloom) before it becomes a boll, and the cotton bollworm, which damages the boll after it has formed. Both lygus and bollworm damage must be minimized for the cotton grower to make a profit. Excessive spraying for lygus in July, however, can get the cotton grower on an insecticide treadmill by triggering a bollworm outbreak in August. A July lygus spray can reduce bollworm predator populations to the point where bollworm populations explode to levels that can require weekly treatment.

Prior to 1971, the university approved guideline for treating lygus was to spray when a count of 10 lygus per 50 sweeps of an insect net was attained; each nymph (immature lygus form) was counted as 2 lygus. This guideline was used by both independent entomologists and insecticide fieldmen. The result was widespread spraying for lygus in July and August and consequent widespread spraying for bollworm in August and September. Not incidentally, bee losses were also high.

In 1971, the university guidelines allowed up to 20 to 30 lygus per 50 sweeps after the initial fruiting stage because it was felt (and subsequently proven) that cotton could tolerate far higher populations of lygus when square and flower populations were also high. In 1973, a sliding scale lygus count was introduced by university and USDA personnel. The sliding scale lygus count considered the ratio of lygus to cotton squares and flowers (squares and flowers had to be counted as well as lygus) and counted a nymph the same as an adult. Cotton fields that would have been treated at the old 10 lygus per 50 sweep criterion were not treated because they had a high enough population of flowers to withstand economic damage. A few fields were treated early in the growing season that would not have been treated under the old criteria; such fields had a low square count and treatment was usually done early enough (May, June) so that bollworm predator populations were not affected and subsequent bollworm problems did not develop. (Early season or pre-bloom insecticide applications are not nearly as hazardous to bees as later season applications).

The sliding scale lygus count has been well publicized and has increased in popularity and usage since 1973; it is used almost exclusively today by both independent entomologists and fieldmen-salesmen. The result has been drastically reduced insecticide use – from 5 to 10 applications during the season to 1 or 2 and in many cases no applications – and little or no bee poisoning. The significant drop in bee poisoning in California in recent years is due directly to the change in cotton insect management in the San Joaquin valley. Unfortunately bee poisoning losses on other crops and in other cotton areas have not changed much over the same period.

For those that like heroes and villains, the villain that caused untold bee losses in San Joaquin valley cotton prior to 1973 was the 10 lygus per 50 sweep treatment count not the commission hungry insecticide salesman. The heroes are those that came up with the sliding scale criterion although, as with any discovery, they have to be asking themselves why they didn’t think of it before.

Where standardized, publicized criteria such as insect counts are available, insecticide salesmen follow the same guidelines as independent entomologists. The difference in many cases is that if the insecticide salesman comes up with an insect count that does not require treatment, he will double check to make sure the count is accurate – the count showing a treatment is necessary will not be scrutinized closely. If the independent entomologist comes up with a count that requires treatment he will re-check several times to make sure that the count is accurate. The independent entomologist undoubtedly spends more time checking fields since he is well aware that reduced insecticide bills help to pay for his services. The farmer that allows insecticide fieldmen to make insect counts and insecticide recommendations is aware that he is probably making more insecticide applications than he would if he used an independent entomologist. He feels, however, that the money saved on insecticides would not offset the cost of hiring an independent entomologist.

Where standardized treatment criteria have been established and proven for a crop, such as the sliding scale lygus count for cotton in the San Joaquin valley, it is extremely difficult for the insecticide salesman to recommend unwarrented applications. The insecticide salesman that would falsify insect counts leaves himself wide open to both competitor salesmen and independent entomologists. In California, where pesticide fieldmen are licensed, the fieldman that falsifies an insect count runs the risk of losing his license if such a falsification is discovered by the county ag commissioner’s office.

In the San Joaquin valley it has been found that making lygus, square and bloom counts is an arduous task requiring patience and physical conditioning more than technical training in entomology. It is a task that trained farm workers can do just as easily, and probably better than trained entomologists – and at far less cost. In virtually all cases, decreased insecticide use requires more thorough field checking. If the field checking is more costly than the insecticide application there is no incentive to pay for it. Field checking by trained bug counters (which could be low skilled farm workers) would be far cheaper than field checking by trained entomologists just as beehives (of equivalent strength) rented for pollination by beekeepers are usually cheaper than those rented by apiculturists.

Where standardized treatment counts are available, much of the mumbo-jumbo of insect control is eliminated. A technical knowledge of “the entire vast entomological and total biological complex including inter-dependent and constantly shifting macro- and micro-sub-ecosystems” (or insect control) is needed to come up with easy to follow insect control guidelines. Such knowledge should not be required to use the guidelines. The intention here is not to downgrade the trained entomologist – his skills are better used in coming up with better treatment criteria and better methods of monitoring insect populations.

Citrus spraying in the San Joaquin valley

Most or all cases of over application of insecticides occur when treatment criteria are vague or lacking or wrong (as in the case of the 10 lygus per 50 sweep cotton criterion). The absence of specific, standardized, easy to follow treatment criteria encourages the overuse of pesticides and makes it far easier for the pesticide salesman to sell insurance sprays. Citrus insect control in the San Joaquin valley is a good example. Sprays for both worms and citrus thrips are applied while there is bloom on the trees with consequent bee losses (peak bloom sprays have been greatly restricted because of honeybees). Several treatment criteria for worms are available – one should be decided on, then standardized and publicized, so that everyone is aware that insecticide applications are only required when the treatment level is reached.

Development of treatment criteria for citrus thrips is a much more difficult task. Citrus thrips are tiny insects, barely visible to the naked eye. They feed on the tiny immature orange and can cause significant economic damage if not controlled***. In addition, citrus thrips are easily confused with flower thrips, a species of thrip that is far more abundant in citrus groves but one that does not cause economic damage. With a little training, using a magnifying glass, anyone can distinguish between the two species, however the distinction is rarely made and many growers who say their grove is “lousy with thrips” that must be sprayed have not verified the presence of a single citrus thrip.

Because no treatment criteria are available and because of the potential damage that can be caused by the citrus thrip, most citrus growers automatically (and understandably) apply a “petal fall” spray and some growers apply a “pre-bloom” spray for citrus thrips control; (there is enough citrus bloom open during “pre-bloom” and “petal fall” to cause significant bee losses). Treatment criteria for citrus thrips control may require frequent, even daily, field checking during the critical potential damage stage. It is possible that field checking for citrus thrips may not be economical (i.e., the cost of the field checking may exceed the cost of a thrips spray) however an attempt at establishing a standardized treatment level should be made. Automatic petal fall citrus thrips sprays may be justified, but they should not be made under the guise of field checking unless the field checking is actually carried out. The sloppy terminology “thrips spray” should be discarded; “citrus thrips” or “flower thrips” should be specified.

Controlling insecticide applications

There are some that argue that all insecticide recommendations should be made by trained, licensed, independent entomologists with no ties to insecticide sales. At first glance this seems like an ideal answer, however a closer look reveals some flaws. What would happen if every insecticide application required a written recommendation from an independent entomologist stating that the application was needed? There are some clues in the beekeeping industry that would help to answer this question; these clues may be too close to be clearly seen.

What would happen if beekeepers could not treat for wax moth but would have to obtain a written recommendation from an independent entomologist stating that treatment was necessary? It is likely that the amount of pesticides used for wax moth control would be reduced, but that the cost of paying for the time of a trained entomologist would far exceed any savings in pesticides. Honey and pollination prices would have to rise for the beekeeper to maintain a profitable business.

The actual necessity of most drug applications for brood disease control would be difficult for anyone to prove although it could be argued that preventative treatment was a necessity. In the absence of insect treatment level criteria, farmers could also argue the necessity of preventative treatment.

Most beekeepers purchase wax moth and foulbrood control chemicals directly from a chemical outlet or bee supply house. There is little advertising for such chemicals and beekeepers are rarely contacted on a regular basis by chemical salesmen. Although there are no statistics, it is likely that the degree of overuse of chemicals by beekeepers in the absence of sales pressure is equal to or greater than the degree of overuse by farmers who are subject to sales pressure. Would beekeepers use even more chemicals if all chemical sales to beekeepers were made by chemical company representatives? Maybe, but it is also possible that beekeepers, suspicious of being duped, would pay closer attention to the actual need for chemical applications and would use less chemicals. In addition, it is possible that chemical salesmen would provide educational literature on treatment criteria that would result in less chemical use by beekeepers.

Those who advocate the use of independent entomologists to make all insecticide recommendations make the idealistic assumption that it can always be determined whether or not an insecticide application is actually needed. There are many situations in which even the most learned entomologist would have to answer “I don’t know” if called on to determine if insecticides were actually needed.

Some independent entomologists have developed their own treatment guidelines where standardized guidelines are vague or lacking. However, the most successful independent entomologists today are not necessarily the most learned entomologists but are strong in administration and public relations, both staples of any successful business. These entomologist-businessmen apply systematic field checking methods usually using lesser skilled employees to apply available insect treatment level criteria. Their decisions are subject to second guessing and sniping from the chemical representatives on the one side and from those that look on any chemical application as an unwarrented assault on Mother Nature. Independent entomologists perform a useful service in an often thankless profession but they are not necessarily the panacea for reducing insecticide use. Requiring all insecticide recommendations to be made by independent entomologists without also supplying specific treatment criteria for every situation would not significantly reduce insecticide applications. If specific treatment criteria were available for every situation, then the need for the exclusive use of independent entomologists would not be critical since it has been shown, at least in California, that abuses in chemical application are rare when standardized treatment guidelines are available.

Statement 5., Most insecticide applications are not actually needed, was left unanswered because it may be impossible to answer. On crops where good criteria for insect treatment exist (e.g., the present situation on cotton in the San Joaquin valley) most insecticide applications are actually needed. On crops or in areas where there is insufficient treatment level criteria it is quite possible that most insecticide applications are not needed. In many situations (e.g., citrus thrips control) the cost of determining if a spray is actually needed may be excessive. Overall, it would be difficult to determine if most (over half of) insecticide applications are not needed, but it is likely they are not. The above statement should probably be labeled “True” or better, “Yes, but….”.

The Future

Beekeepers should use caution before joining forces with the anti-pesticide coalition. The benefits of requiring a farmer to have a written spray recommendation from an independent entomologist may be offset by the higher food prices that everyone would have to pay. Beekeepers should not forget that the anti-pesticide coalition was indirectly responsible for the widespread use of the “safe” insecticide, Sevin, and currently for the development and potential widespread use of the “safe” micro-encapsulated insecticides.

A key (but not the total answer) to less insecticide use is the establishment of accurate, standardized, publicized insect treatment criteria. These criteria should be stated in simple language and should be of a nature that an unskilled farm worker could use them with a little training. The absence of treatment criteria allows the chemical salesman (scrupulous or unscrupulous) to throw a worm eaten leaf, including worm(s), on a farmers desk with the implication, often unstated, that “we’d better start spraying.” In many ways, pesticide salesmen are similar to insurance salesmen, gently illuminating potential catastrophes while presenting a relatively cheap form of coverage. Treatment level guidelines allow the farmer to make an intelligent decision as to whether the insurance is a good buy.

Beekeeping organizations should consider donating money toward the establishment of insect treatment guidelines on crops in their area whose treatment by insecticides constitutes a hazard to bees. If nothing else, such donations would be good public relations at a time when many farmers are becoming increasingly resentful of the honeybee’s influence on insect control programs.


* “Insecticide treadmill” occurs when the first insecticide application leads to another and another and another. This happens because the predator (good) insects are killed and/or the harmful (bad) insects develop insecticide resistance.

** integrated pest management is the use (integration) of all available methods of insect control, including insect monitoring (bug counting) and chemicals and is used by both independent entomologists and insecticide fieldmen. Although “integrated pest management” is a relatively new term, it’s principles have been used for years.
eco-system management
has a number of definitions depending on who uses the term. Those who practice integrated pest management could be considered eco-system managers. Some bug counters like to be considered eco-system managers just as some beekeepers like to be considered apiculturists. Because eco-system management cannot be precisely defined in a few words, it is a term that is better left unused.
*** Citrus thrips damage is mainly cosmetic; citrus thrips feeding leaves brown scars on the skin of the orange – the edible portion is unaffected. Then farmer, however, receives a much lower price for scarred oranges. A case could be made for using the money currently used for citrus thrips control to educate the consumer that beauty is only skin deep.