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  • Winning Respect for Biological Pest Control
    50 000 beetles and released them in the valley a reenactment of the original biological control program the saving of citrus in 1889 This didn t get reported at the time I don t know why but it took 20 years to publish the work that we did with evaluating the effects of DDT on the beneficial insects in citrus SEASONAL CHEF One of your colleagues from that time Robert van den Bosch wrote in his book The Pesticide Conspiracy that he was reviled for his pioneering work on biological control Did you ever experience hostility DIETRICK The first project that made some people mad was with biological control of the alfalfa aphid The infestation began just east of Brawley Probably somebody brought an infested bale of hay from the Middle East The aphid just took off and started to spread Pretty soon we heard that farmers were spraying three times per cutting Well they had a problem Clearly the pesticide wasn t working After you devastate the area with chemicals the pest population explodes on you The last thing they do is call in biological control We got 100 000 for a three year project We started to grow alfalfa in greenhouses We found parasites right away in the Middle East We found three parasites that attacked the aphids We released them and soon we had 10 or 12 fields with well established parasites We had field days at the research station and we would give farmers a stalk with parasitized aphids tell them to take it home and put it in their field In about one year the 9 million parathion spray program on alfalfa dropped to less than half a million That s kind of when the crap started to hit the fan I remember one day when a chemical company development guy came in and he said I m going to get your job But they never did acknowledge that the biological control was responsible It was typical of the way they have downplayed biological control It s not even a conspiracy It s just that these people think alike It you think alike you don t have to conspire There was just no way to stop the marketing steamroller that took place with DDT after World War II The chemical industry realized they had these powerful tools that were just waiting to be exploited And it wasn t long before the marketing people took over the chemical industry The entomologists lost control of it And the companies began hawking chemicals like they were drugs They were enormously successful for a while SEASONAL CHEF When you first went into business as a biological pest control adviser in 1960 were there any customers for your service DIETRICK It wasn t easy If the university tells the farmer to spray and the chemical company tells him to spray and the county agent tells him to spray and nobody tells him not to spray see how easy it is

    Original URL path: http://www.dietrick.org/articles/seasonal_chef.html (2016-04-30)
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  • War on Bugs
    began visiting farmers and consulting with them on the best cultural and biological methods for controlling pests in their fields the first generation of applied insect ecologists was born In 1971 Rincon merged with the Vitova Company to become Rincon Vitova Insectary Now after close to 50 years of research Deke is still convinced that if cultural and biological controls are applied properly pesticides are completely unnecessary You know it s a big argument What is a pest he says thoughtfully A pest to a lot of people is just a name of an insect and one of them is too many But really a pest is any insect that is out of place and is bothering you or economically bothering you a farm and so you can tolerate a certain number of pests But when DDT came along the vision was that you could rid the world of insects And that s what they set about to do The Department of Biological Control was appalled by this lack of understanding of the ecology because ridding the world of insects would be impossible I call it the war on bugs he says laughing We always have in this country a war on drugs or a war on whatever Everything s a war None of this has been easy there has been resistance every step of the way from the Pesticide Control Authority PCA from the pesticide industry and from the farmers themselves Although the dangers associated with pesticide use are now well known farmers and commercial gardeners feel compelled to use them because as Deke explains common knowledge has held that in the world of agriculture the only good bug is a dead bug Of course there is hardly anything further from the truth Not only are there such things as good bugs they are abundant and the people at Rincon Vitova believe they are far more effective than pesticides Pesticides not only poison the environment they also upset the natural balance that occurs within the ecosystem of a field or farm and by doing so cause the field to become dependent on chemicals and eventually less productive Like drug addicts fields get so they cannot live without the very chemicals that are making them sick Thus sometimes Rincon Vitova must step in and act as a sort of farm rehab weaning a farmer off of his chemicals and onto a steady diet of alfalfa and beneficial insects until they are sober and functioning better than ever The worst thing about these pesticides says Jan Dietrick Deke s daughter and Rincon Vitova s manager is that the insects develop resistance to them so fast so they re such a short term solution They re distracting the agricultural the horticultural community from continuing to develop biological methods They re kind of like short term Band Aids delaying the evolution of long term permanent biological methods You can t say low risk pesticides are bad They re a lot better than DDT

    Original URL path: http://www.dietrick.org/articles/war_on_bugs.html (2016-04-30)
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  • The Press, Riverside Article
    costs On rows of banana squash on shelves scale pest insects are growing in heavy incrustations and this presence of pest insects says something about biological control IN ORDER TO produce good insects you must have bad ones he explained The good ones feed on the bad ones often on a specific bad one leaving other insects alone In the railroad car where housefly enemies are produced there s a noxious odor of rotting stuff for the flies to eat The Rincon Vitova inventory includes the pale green lacewing for use against aphids mites moths and caterpillars Ladybugs are collected in the field In the insectary they are preconditioned so they re ready to feed and lay eggs when they encounter aphids Trichogramma wasps tiny and harmless to people are parasites on moth and butterfly eggs They are used to combat the worm pests of cotton and numerous other economic and ornamental plants Everett Dietrick tends his banana squash hosts to scale insects which in turn are used as hosts for eggs of the parasitic golden chalcid a beneficial that attacks red scale in citrus orchards SOME BENEFICIAL insects like lacewings are sold in larval form Trichogramma golden chalcids and some others are sold as adults ready for release Fly parasites are delivered while they re maturing in fly pupae to be placed where they ll emerge to protect poultry or cattle The latest Rincon Vitova product list has 35 different Insect species The last work Dietrick did as a UCR technician was in connection with the outbreak of the spotted alfalfa aphid in the 1950s Typically it had arrived from the Middle East where it is scarce and evidently held under some type of natural biological control In Riverside County it multiplied as an insect can under the right circumstances with a plentiful food supply alfalfa and without natural enemies Several parasite wasps were found In the Middle East to combat the aphid In that work Dietrick said we field harvested the parasites and moved them to other fields It took two years to reach a natural balance that might have taken 10 years to accomplish by leaving the parasites to spread natural DIETRICK SAID many factors contribute to the growers dilemma with insecticides Initially he said the new insecticides clean fields and groves of harmful insects The early result is usually big crops with few rejects Sometimes as in Imperial and Palo Verde Valley cotton the spray program is area wide most growers under a uniform contract to spray at regular intervals whether they need it or not Such a program Dietrick said eliminates beneficial insects Eventually the damaging pests become resistant through the survival and reproduction of the few that are naturally resistant By contrast the integrated control program calls for releasing beneficial insects only after the first damaging ones appear so beneficial ones will have food to encourage them to stay ANOTHER PRACTICE goes hand in glove with the goal of completely eradicating insects Dietrick Said

    Original URL path: http://www.dietrick.org/articles/riverside_press.html (2016-04-30)
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  • Commercial Production of Entomophagus
    farmers with total of 9 400 acres has kept average pesticide treatments below one application per acre per year for over 50 years One might ask why the existing commercial insectaries are not producing more new and varied biological controls on contract or for sale If you think about it the vast array of natural enemy complexes are not being marketed because there is not enough demand Needs are often very specific and within limited time frames Losses from variable weather patterns affecting the window for releases shipping and now the growing administrative costs of compliance with regulatory agencies over the transport of biological organisms not to mention the capital supply and human resource development costs associated with developing a new mass rearing system result in little if any profitability When you consider that after all of this investment the organism is not patentable and belongs to anybody who wants to buy it and piggyback on the original producers developmental efforts it is no wonder that new organisms are not arriving in the marketplace the farmers would like Farmer insectaries avoid many costs of commercial insectaries They give preferred service in timing releases Specific strains most appropriate to the geographic region are produced There are no marketing and distribution Costs Combining insectary beneficials with monitoring by affiliated entomologists to maximize indigenous natural enemy complexes allows for maximum flexibility and minimum losses In addition to the mass rearing and monitoring resources that the growers can fund cooperatively classical biological projects can also be organized most cost effectively by cooperatives with technical assistance from universities Governments and universities are not obtaining the needed funds to conduct these essential projects to meet demands of increasing numbers of exotic pests being spread around the world by travel and commerce Even when governmentdoes acquire the

    Original URL path: http://www.dietrick.org/articles/bc_by_farmer.html (2016-04-30)
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  • Argentine Ants Must Be Suppressed
    an organic vegetable greenhouse where Argentine ants were thriving on honeydew from aphids spreading along ant trails A conventional grower would have sprayed for aphids reducing the food supply to the ants and slowing down the whole process of ant induced aphid damage but might not have sought a root cause that would have prevented the need of pesticide in the first place Being an organic grower biological control was desired and indeed a great deal of biological control activity was present Though some of the aphid species did not have parasitoids a parasitoid of green peach aphid Aphidius matricariae was present on the pepper plants It was able to evade the ants but it arrived too late and worked too slowly without the help of predators Plenty of ladybugs came in but their effectiveness was deterred by ants and their eggs and larvae offered more nutritious food for the ants Releases of green lacewing to help the ladybugs and aphid parasitoids only provided additional protein for the ants The Aphidius parasitoid eventually temporarily eradicated green peach aphid and saved the peppers after which a rise in hyperparasites of Aphidius brought the system into equilibrium However the ants immediately threw it off balance again Where the ants had caused the secondary mite outbreak on the tomatoes it was a pretty hopeless situation that could have been avoided The effects in citrus were studied many years ago Where ants were excluded or removed biological control was optimized Where ants were allowed to interfere all pests of citrus were observed to increase When augmentation of natural enemies is an option it is only cost effective when ants are excluded Biological control by natural enemies cannot be evaluated fairly in the presence of Argentine ants any more than it can in the presence of dust and pesticide drift Argentine ants form new colonies rapidly wherever scouts mark out food sources In spring and summer there is a progressive increase Cool weather slows ant activity and allows struggling populations of beneficials to destroy pests on many plants When old crops that are left in the field are ant infested the decaying plant material which is normally a useful habitat for beneficials only serves this role for the benefit of ants While wet or foggy weather slows ant activity heavy winter rains will drive ants from rain soaked fields into greenhouses houses and barns Argentine ants can be baited with several ant syrups that have poisons When the bait is carried to the nest and fed to the brood and poisons the queen the colony is destroyed A new queen must be fed the royal food that transforms her into a queen This takes time which can then be spent disrupting ant nests by irrigation cultivation and reduction of old crops and also repeated trail disruption Ants do not nest where growing plants or mulches cover the ground They prefer sun baked soil to nest under and may even clean the nest area of vegetation

    Original URL path: http://www.dietrick.org/articles/deke_argentine_ant.html (2016-04-30)
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  • Biological Control: An Ecological Approach
    reduce the remaining population of adults on which they feed Thus the idea is to attract and retain as many kinds of beneficial insects as possible in the garden as a general buffer against pests This can best be accomplished through a diversity of plants Different kinds of plants attract different kinds of insects resulting in a biological balance in the garden Plant as wide a variety of plants as possible and plant them in small blocks Plant flowering plants as well as vegetables and fruit trees they will not only make the garden more beautiful but will also help create a biological balance by providing pollen and nectar for the beneficial insects Strong healthy plants can outgrow many potentially serious pest situations humus forming mulch can help control weeds and provide additional plant food while helping retain moisture in the ground Limited numbers of natural grasses and even weeds can provide a protective niche for predators and parasites providing host insects nectar pollen and sources of water in dews and moist organic litter on the soil surface Beneficial insects are small with a high surface to volume ratio and they lose their water content quickly in unfavorable environments In order to survive they must be able to replenish their water content In general most insects need a drink of water each day if water is not provided in the habitat predators may turn to the plants as a source of moisture and thus become minor pests themselves It is very important therefore that we provide free water in the garden for the beneficial insects In addition to diversifying plantings try to keep a sequence of plants planted in the garden at all times even if this means planting green manures or sod grasses for the compost heap Crop rotation can be accomplished in the garden just as it is on the farm only on a smaller scale especially if the plantings are in permanent beds with permanent walk areas This sequence of plantings which is just a matter of planting whatever can be grown in each season throughout the year will retain the complex of insects in the garden When the garden is abandoned during the winter the insects will overwinter in the plant refuse Surplus plant residues litter and other garden waste products should be rapidly composted to remove them as potential habitats for the pests This composting helps provide the decomposing organisms which are a valuable alternate food source for the beneficial insects A constantly active garden will retain a constantly active complex of insects ready at all times to help control garden pests All in all the more diversity the better The more plants in a garden the more kinds of insects will reside there The more kinds of insects in a garden the better the biological balance will be The many varieties of insects will help control each other and the beneficial ins will remain there even when pest populations are low because there will

    Original URL path: http://www.dietrick.org/articles/deke_bc_ecological_app.html (2016-04-30)
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  • Commercial Production of Entomophagus
    control Chemical control advocates generally ran their test plots in fields where the target species flourished It was logical that they seek those fields in order to obtain the data needed about the effects of pesticides on those pest species These fields were high in pests and low in predators and parasites Conversely entomologists interested in biological controls ran their studies in fields that had relatively large populations of predators and parasites compared to pests Their experimental requirements needed fields free from pesticide and other habitat interferences to explore the effects of natural enemies and specific biological control agents on their host populations Clearly these were two different kinds of field situations The former was deficient in predators and parasites Even those natural enemies present were destroyed under the small plot experimental design Pesticide drift and interplot migration of the more mobile predators and parasites adversely affected the biological control that was present The latter biological control experimental field situations were isolated from effects of pesticides and the full range of natural enemies were present Large experimental plots were used to minimize the drift effects from any pesticides used There is little wonder that there exists such a divided opinion among entomologists regarding biological controls It is difficult to form a good opinion about natural enemies if there are none in the fields chosen for studies The devastating interpretation of this situation occurred when the untreated check plots in the small plot pesticide screening experiments were referred to as being representative of biological control failures Instead of measuring the ineffectiveness of the natural enemies or lack of them these entomologists demonstrated the detrimental effects of pesticides on those few predators and parasites that were attracted to these check plots in search of their prey These checks were pesticide interference plots Conclusions on economic thresholds were derived from such fields that were deficient in natural enemies The lack of any biological control suppression on the pest populations led to the setting of pest density levels that were far too low for fields where natural enemies were allowed to help suppress the pests Pest management with natural enemies can flourish where population monitoring allows for minor pest spots to appear in fields in order to attract and multiply the natural enemy complex that will predictably control the pests and result in a marketable harvest Pest control advisors face three kinds of fields each time they check the farms of their clients Clean fields are quickly identified and little time is spent in them Dirty fields full of pests with few natural enemies are also quickly managed by making the proper pesticide recommendation Most of the advisors time is spent monitoring the insect populations in the borderline fields which are not clean of pest species but have a moderately high level of natural enemies There is time to watch and wait because the pest populations do not Increase as quickly where natural enemy suppression is occurring Some of these develop sufficient natural enemies for the pests to be biologically controlled and the use of pesticides can be avoided Farmers who buy biological control products try to help the natural enemies in these borderline fields This commonsense idea of periodic augmentation of insectary products in infested fields to help the natural enemy suppression of the pests is the foundation for the use of such biological controls in agriculture Such pest management is based on principles of ecology the recognition that 100 mortality of all pests is not desirable and on attempts to avoid as much as possible the impact of pesticides and other habitat disturbances on beneficial insects DeBach 1969 1974 Dietrick 1972 Kilgore and Doutt 1967 EVOLUTION OF THE FREE ENTERPRISE INSECTARY Rincon Vitova Insectaries Inc began as a part time partnership Rincon growing Crypts a mealybug destroying coccinellid named Cryptolaemus montrouzieri Mulsant This Australian predator had been mass cultured for many years by county government insectaries individual farmer owned insectaries and farmer association insectaries Fisher 1963 The county effort which had used tax money for support but gave the insects to farmers free of charge was discontinued for budgetary economy and other reasons A ready market for rearing and selling these beetles thus became available It quickly became clear to us that this potential market would not develop The weak endorsement for these inoculative type releases from nearly all agricultural researchers coupled with the euphoria for chemical pesticides almost completely stopped the use of this product Crypts are still used today by our insectary and at least one citrus farmer cooperative insectary continues to grow several millions of these beetles each year as it has for nearly 50 years The lesson that Rincon Insectary learned was that farmers would not necessarily buy products that were previously obtained free of charge Rincon Insectary then found a market for Trichos a trichogrammatid parasite of eggs of the cotton bollworm moth Heliothis zea Boddie now Heliocoverpa zea that were being cultured by a farmer in west Texas The potential market for these Trichogramma spp was larger than the supply Costs for production were greater and less reliable in Texas than in Rincon s coastal climate and an agreement was reached for Rincon Insectary to grow the insects and the Texas partners to market them In spite of the controversy that had raged over inundative releases of Trichogramma spp DeBach and Hagen 1964 the farmers were eager to acquire and use the product Rearing methods first proposed in the early twenties were resurrected Flanders l930 l934 The farmers bought Trichos for the same reason that they bought ladybird beetles the results were satisfactory and it was commonsense to help the existing natural controls This west Texas cotton growing area was blessed with large populations of natural enemies and the use of ladybird beetles Trichos or any other species of insects known to help suppress bollworm populations would have satisfied the customers These products were more economical than pesticides and their use lessened the farmers worry when cotton bollworm moths were reported to be flying They provided the pest control advisors a logical alternative product to counteract the fear generated in the farmers by the unrealistic economic thresholds set for bollworms The recommendation to treat for bollworms when 4 out of 100 cotton plants were infested with eggs of bollworm moths was clearly set too low for fields that had natural enemies that were destroying these eggs The Trichos released to help attack the populations of bollworm eggs was a commonsense approach The results were generally favorable in fields that had not received earlier applications of pesticides for such minor pests as thrips aphids and mites The natural enemies in these untreated fields had been allowed to increase their populations on these minor pest problems thus controlling them biologically The questionable recommendation to clean up these early pests so biological controls could work had not yet reached these farmers With the natural enemy complex capable of control many farmers experienced good results solely with releases of Trichos With the use of D Vac trade name for sampling equipment manufactured by D Vac Company P 0 Box 2095 Riverside CA 92516 vacuum insect sampling equipment we were able to show customers that most bollworm eggs were destroyed and that the few one day old worms that did emerge were victims of predators before they grew to be three to four days old Dietrick 1961 Dietrick Schlinger and van den Bosch 1959 The low survival rate of these eggs and small worms was shown to be a measure of the effectiveness of biological control These observations eventually resulted in economic thresholds being raised for untreated cotton fields The 1973 cotton pest and disease control guide of the Division of Agricultural Sciences University of California states In fields not previously treated for insect control insecticide treatment for bollworms is indicated when 20 small worms per 100 plants are found This economic threshold was compatible with the use of insectary products The door was open to begin talking to more and more cotton farmers about biological control We showed them fields where effective populations of predators and parasites destroyed bollworm eggs overnight We also were able to explain to the farmers that in those field situations where nearly all bollworm eggs hatched and grew into full grown worms there was no buffering natural enemy complex to suppress these pest populations and much cotton was destroyed as a result About that time Rincon learned another lesson about the insectary business The marketing partner in Texas decided to build his own insectary with funds collected from farmers and owed to Rincon As a result we lost over 80 of our business and gained a bad debt as well This was only the first of many such experiences The method of payment for insects came long after harvest and the delivery of our products but the insectary borrowed the money to set the cultures six months in advance of the market The live insect products were grown delivered and released on the farms throughout the growing season Usually only after the farmer sold the crop did he pay the insectary Since biological controls were not considered pest controls they could not be included in the bank loans set aside for chemical pesticides and other production financing Some farmers simply never paid after all there was no proof that releasing Trichos had helped The problems of late payment and bad debts are enough to make most potential investors shy away from this business Fortunately there was sufficient financial support to keep us in the struggle We found new markets diversified our product line and broadened the areas where we sold these products One such market developed in citrus with the use of the golden chalcid parasites Aphytis lingnanensis Compere and A melinus DeBach These species attack the number one pest of citrus California red scale Aonidiella aurantii Maskell DeBach 1969 One of the farmer cooperative insectaries contracted with Rincon to buy 5 million of the red scale parasites At the same time we borrowed a program from these farmer cooperatives and began contracting with individual farmers for pest management advice and beneficial insect colonizations wherever they might be located We insisted that the advice services include releases of our insectary grown products Trichos were for cotton and the crypts and Aphytis spp were used as periodic inoculative releases in citrus The charge per ha set by the farmer cooperative insectaries was increased to cover the additional travel costs the costs of field monitoring advice and the insectary products This seasonal contracted market gave our business some stability and provided compensation for all the extra insect products that we grew but could not sell over the counter The only real difference between our operation and the farmer cooperatives was the voluntary participation on the part of our clients My observation about these farmer cooperatives is that it is difficult to please continually all of the individual member farmers This voluntary professional client relationship gave our effort considerable freedom for direction We simply had to please enough farmer clients in order to pay our expenses Profits could come from the over the counter sales of insect products Some farmers wanted to believe in sophisticated pest control advice and we convinced them to buy the insects Other farmers wanted to believe in the augmentative releases of predators and parasites so we sold them the insect products and tried to follow up with advice where possible We contacted other independent pest control advisors and found a few of them willing to use our products as part of their advice programs Even competing insectaries have on occasion purchased our products to help fill their market needs These professional client contracts were more like verbal agreements but they provided enough cash flow to keep the business going Even the late paying customers provided a winter income when the payments finally came in We avoided any business ties that would obligate us to any particular market or dealerships We grew as many insects as possible with the resources available and used them in our pest management or sold them as the market developed We had solved the problem of how to be compensated for all the insects that flowed daily from the production units at least during the summer growing season The arrival of the pink bollworm Pectinophora gossypiella Saund as a new pest species in our cotton marketing area triggered an eradication effort by state and federal authorities The blanket pesticide applications required by this effort immediately created another shock to our struggling insectary business Adequate natural enemies for this pest were not available and the eradication procedures advocated for its control were not compatible with our biological pest management programs The effect on our Tricho sales was devastating One group of farmer clients the Coachella Valley Growers Gin had been our customers continuously since 1961 These farmers chose not to apply the pesticides in the eradication effort and thus the federal authorities substituted the sterile moth releases as an eradication procedure This program allowed for biological controls to be used early in the season even though chemical pesticides had to be resorted to in late season We were thus able to continue our programs with these farmers The business lesson we learned from this experience was how to be adaptable We then adjusted our programs to the sterile moth eradication experiment We found new markets to replace the lost ones in other cotton growing areas We helped ourselves by helping cotton farmers in Mexico and Central America to further their insectary efforts We also lengthened our marketing season by delivering our products to Nicaragua We began a new line of parasites that helped biological control of pestiferous flies associated with manure accumulations on poultry farms Legner and Dietrick 1972 These business diversifying actions again created enough income to keep us going During this time we added production facilities by purchasing another insectary known as Vitova a contraction for the Latin vita ova meaning live eggs Research has benefited our insectary a great deal The existence of a commercial insectary challenged researchers to investigate some of the programs that we intuitively advocated doing what seemed obvious from our field observations Influential farmer clients asked questions in important places and research money flowed from various commodity groups for university and government researchers involved in such biological control efforts Our insectary supported research and encouraged customers to fund such research E J Dietrick unpublished The fallout of useful knowledge that comes from such ecological experimentation far surpasses any possible effects that any negative findings would have on our business The problem still lies in finding the funds to study the Implementation of biological controls PROBLEMS FACING THE COMMERCIAL INSECTARY Problems encountered by commercial insectaries can best be solved in the free market place Farmers will discontinue acquiring and using pesticides when they are convinced that alternative pest management is cost effective Rising costs for petroleum based farm chemicals and fuels and narrowing profit margins are forcing farmers to look for more economical solutions than those presently available Farmers presently spend millions of dollars every year for chemical pest controls that may not provide any permanent solutions to the problems When farmers buy chemical pesticides their support goes to further the development of more chemicals Perhaps a financially viable biological control industry can also influence further research and development in classical biological control Biological control importation projects are the main source of beneficial predators and parasites that can be developed as products by commercial insectaries Increasing energy costs are also influencing insectaries that serve the farmers The appropriate ate size firm seems to be one which is small enough to adjust its products and services to meet local needs Maximum use of habitat management techniques that are capable of trapping pests and increasing the populations of predators and parasites can then be used Schlinger and Dietrick 1960 Insect harvesting equipment can be employed to move the surplus natural enemies from fields where pest populations have been destroyed to fields deficient in predators and parasites E J Dietrick unpublished Stern 1969 Stern et al 1964 1965 van den Bosch l969 The local insectary can become abase for pest control advisors for such operations along with mass culturing of certain parasites that can be more economically grown than harvested Probably the single most prevalent problem facing the commercial insectary is the low visibility of biological controls It would greatly help if extension efforts could provide farmers with biological control information with color pictures of the key predators and parasites associated with each crop There are few bulletins that provide do it yourself assessments of key natural enemies Bethell 1978 van den Bosch and Hagen 1966 Perhaps a periodic newsletter identifying the good bugs and their relationship to pest management would enhance the visibility of biological controls Unfortunately the usual endorsement from the entomological establishment including many researchers in biological control is reduced to such statements as It won t do any harm to use them Some of the more optimistic statements are that we do not have sufficient information to recommend for or against the use of Trichogramma chrysopids praying mantids ladybird beetles or any other parasites or predators in the manner proposed for controlling agricultural pests U S Department of Agriculture 1968 Such position papers presumably based on adequate information make it very difficult to sell biological control products Weak statements that call for conservation of natural enemies without identifying the species involved or without specifying which pesticide to use to conserve the predators are also nonproductive There seems to be a strong effort to regulate biological control practices as if they were a threat to society similar to the poisons in our pesticides Certainly no harm can result from predators and parasites known to attack pests and already established in the area One major justification for the commercial insectary is to help with the

    Original URL path: http://www.dietrick.org/articles/deke_com_production.html (2016-04-30)
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  • Integrated Pest Control
    predictable chance of obtaining a favorable balance the crop can always be sprayed This leads us to the second principle of integrated pest control a recognition that l00 mortality of all pests is not required to prevent economic losses This may seem elementary but society has been brainwashed into believing that the only good bug is a dead bug it is important to point out that insects mites weeds etc are pests only when they affect our way of life beyond tolerable limits It is essential to the concept of integrated control that we live with a few pests in order to obtain and retain a favorable balance Strict standardization procedures that do not necessarily give the consumer food of better quality or taste may force the farmer to spray for light infestations of a pest Often any plant damage that might occur would not be harmful to the crop except perhaps in appearance Plants can tolerate low populations of aphids thrips and mites with no intolerable damage affecting profitable production of the crop Instead of spraying the insect ecologist uses these minor pests as food in colonizing additional insectary grown or field harvested predators The challenge for the future is to devise ways to grow and or field harvest sufficient beneficial insects and apply them to the fields by mechanical means in this way biological control could be better implemented and guaranteed and many more fields could be saved from pesticides The third principle of integrated pest control is the avoidance of disruptive chemicals Not all pesticides have adverse effects and certain dosages of conventional pesticides are less disruptive to the existing biological control Backup sprays are applied when necessary but of a kind and in a manner least disruptive Integrated pest control seeks to suppress target pest populations below tolerable damage levels without destroying their biological controls The professional insect ecologist must know how to use pesticides in this way in given situations However because of the polluting side effects of too much pesticide in the environment it is even more important that he know when and where not to use them There is not time to dwell on all the pest control problems that have developed as a result of complete reliance on chemicals a short list would include target pest resistance to pesticides target pest resurgence following treatments secondary pest outbreaks pesticide residue problems in the crop the soil or drift to nearby areas or runoff to streams and drainage and destruction of pollinators and other forms of life beneficial to man In many instances these side effects have created havoc and the undesirable results have more than off set any original benefits It is becoming more and more difficult to kill the target pests economically One often underestimated side problem is the drift of pesticide residues onto nearby crop areas and the widespread effect of destroying favorable biological balances Searching predators and parasites moving over the plants in search of prey are exposed to more

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