Spraying pest control

Insects of many kinds can do much damage in little-used sections of libraries, so the need for good housekeeping and frequent inspection is clear. Insects feed on dirt, and mold breaks down book materials thus providing more food as encouragement for their proliferation. It is possible to arrange monthly pest-control spray contracts relatively inexpensively, a valuable service in bad areas. 

The use of plant extracts for insect control dates into antiquity the use of Paris green as an insecticide for control of the Colorado potato beetle in 1867 probably marks the beginning of the modern era of chemical control of injurious insects. The development of lead arsenate followed later in the nineteenth century for gypsy moth control. The commercial production of nicotine insecticides, the production of calcium arsenate at the time of the first world war, and the use of fluorine, arsenical, and cyanide compounds, as well as other inorganic chemicals for insect control, were important steps in pest control. These chemicals were applied largely by dilute high pressure sprays or dusts. 

No studies were found correlating levels to which humans were exposed with actual body burdens. However, an attempt was made to correlate blood levels of chlordane, which may contain from 6% to 30% heptachlor, to duration of occupational exposure. Blood samples from 51 male pest control operators who were occupationally exposed to chlordane were tested for the presence of chlordane and its metabolites trans-nonachlor, oxychlordane, and heptachlor epoxide. The blood of 19 male workers with no experience spraying chlordane was also tested as a control. Heptachlor epoxide was detected (from not detectable to 1.6 ppb) in 20% of the blood samples from pest control operators exposed to chlordane (concentration not reported). The total chlordane in the blood was low but demonstrated sizable correlation with the number of spraying days and the amount of chlordane sprayed (Saito et al. 1986). 

Saito I, Kawamura N, Uno K, et al. 1986. Relationship between chlordane and its metabolites in blood of pest control operators and spraying conditions. Int Arch Occup Environ Health 58 91-97. 

Wasps are particularly effective at controlling this pest. Grow crops under fine mesh to exclude the butterflies. Biological control Spray Bacillus thuringiensis (Bt) on infested plants (this is only available in large "commercial grower" packs). 

The quick-breaking emulsion concept developed by DeOng et al, (6) in 1927 materially improved the insecticidal efficiency of spray oils against insect pests of citrus. After annoimcement of these results, a large number of proprietary spray oils was placed on the market in California. During the next several years considerable variation in pest control and in damage to citrus orchards occurred with oil sprays. 

Products of the petroleum industry have been used in agriculture for the control of pests practically since the initial recovery of oil from the earth. The early uses were as dormant sprays for deciduous fruit trees and for weed control. The development and expansion of petroleum products and petroleum chemicals in agricultural pest control fields have closely paralleled the technological development of the petroleum industry. 

Whenever applied, IPM practices have consistendy resulted in decreases in insecticide applications of 50 to 90% over conventional spray programs. By encouraging natural enemies, IPM practices markedly decrease the rigor of natural selection by pesticides that is responsible for resistance. Natural enemy preservation also prevents the great fluctuations and suiges in insect pest populations observed after the injudicious use of broad-spectrum insecticides. Under the IPM concept, insecticides are generally used when other practices are inadequate and the pest population reaches the economic threshold. In order to make the IPM concept effective, insecticides must be used as selectively as possible, with minimal disturbance to all other elements of the ecosystem. Thus IPM practices are essentially blueprints for the proper use of insecticides in insect pest control. 

As the name implies, this group of insecticides used in water-soluble formulations easily dissolves in water. In this formulation, the technical-grade material is a finely ground solid. It can be added to the spray tank, where it dissolves quickly. Once dissolved, an SP becomes an invisible solution that can be applied to approved surfaces without constant agitation. The most common SPs used in pest control are Acephate Turf and Acephate PCO Pro (Orthene) concentrates. 

Pesticides may be periodically inttoduced into indoor air by direct application (e.g. insect sprays and bombs, disinfectant sprays and room deodorizers). In addition, there are often sources that continually emit vapors into the living space (e.g. continuous evaporation of residues from crack and crevice treatments and emissions from pest-control strips or other devices). Whether used inside the home or office, or outside on the lawn or garden, pesticides accumulate on indoor surfaces, especially in carpet dust, and also in upholstery and in or on children s toys (Lewis et al 1994b, 1999 Simcox et al., 1995 Nishioka et al 1996, 1999 Gurunathan et al., 1998). 

Predatory mites are highly sensitive, however, and are inhibited or killed by various pesticides. This should not really be a problem under organic conditions, but sulphur is often sprayed in organic orchards, where it is one of the most important pest control agents. Frequent spraying of high doses of sulphur, however, can cause severe damage to predatory mites. 

This device causes a fixed rate of pesticide to mix with the water flowing through the hose to which it is attached. The mixture is expelled through a high-volume nozzle. These sprayers usually hold no more than one quart (one liter) of concentrated pesticide, but because the concentrate mixes with the water, they may deliver 20 gallons or more of finished spray solution before refilling. Figure 8.3 depicts a hose-end sprayer used for small pest control projects. 

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