Termites can be controlled.pdf

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extracted text: A few pointers Can □ mong the insect pests, one of the most destruc tive is the termite. Un fortunately, this is a pest that thrives very well in the Philip pines. The damage inflicted by termites on property all over the country has been estimated at over a million pesos per year. Termite development in our country is aided by many fac tors, among them high humid ity, adequate rainfall, favorable temperatures and abundant food. Here, where the principal construction material is wood, termite control should receive greater emphasis. Considered most destructive of the 39 known species of ter mites in the Philippines is the subterranean “milk” termite (Coptotermes vastator). This pest is widespread from sea level up to an altitude of 5000 feet. It can readily be recog nized by the milky secretion of its soldiers. This secretion is By Mitron Paniqui a toxic substance that protects it from its mortal enemy—the ant. This termite builds covered runways or tubes over other materials to reach wooden structures. The “milk” termite requires a great deal of mois ture; hence their usual point of attack is the dampest area of a building. Another common type is the Macrotermes gilvus Hagen, a termite that builds mounds in the open field, around fence posts, park benches and dead logs. Although this type is not as destructive as the “milk” termite, it ruins gardens, graz ing land and disfigures the land scape. The Heterotermes philippinensis is a rare type. Its size and habits are like those of Cop totermes. They also inflict dam age on buildings and woodwork. November 1958 35 The Heterotermes can be dis tinguished by the narrow and rectangular shape of the heads of its soldiers. There are many ways of con trolling termites. One of the most important is the adoption of good construction practices. It is necessary that wood is put out of the reach of termites. This is usually achieved by con structing concrete foundations and floor slabs and placing the wordwork above them. Once this is done, additional meas ures should be adopted such as putting metal shields over the concrete and digging narrow trenches around the foundations and filling them with cresote or oil reguarly. This method, how ever. is both expensive and un sightly. A better method would be to use woods that are imper vious to termite attacks, such as ipil or molave. However, if one cannot afford this kind of lumber, one can have the wood treated with chemicals. The ini tial cost is rather high but in the long run it is economical. Good sanitation and efficient drainage all help in termite con trol. Damp areas add depress sions that catch water should be drained and thoroughly dried. effective supplement to good construction methods is the use of soil poisons. Soil poisons can be sprayed on the ground or mixed with the soil before the construction of the building. Soil poisons can also be applied around the founda tions of existing buildings or injected into cracks and holes in the concrete. Among the chemicals now in common use as soil poisons are the following: (1) Aldrin, .5 to 1% of the effective ingre dient in No. 2 fuel oil, applied at the rate of 1 pint per square foot or 4 gallons per 10 cubic feet of soil, can show effective results for a period of seven years. (2) Benzene hexachlo ride, containing 0.8% of the gammar isomer in No. 2 fuel’ oil or in water emulsion, ap plied at the rate of 1 pint per square foot or 2.5 gallons per 10 cubic feet of soil, is effec tive for 8 years. (3) Chlordane, at a concentration of 2.0 per cent of the active ingredient in No. 2 fuel oil or in water emul sion applied at the rate of 2 pints per square foot or 7.5 gallons per 10 cubic feet of soil. This chemical is better than the others because it is less harm ful to the plants. (4) D.D.T., 50% in No. 2 fuel oil, applied 5 gallons to 10 cubic feet of soil, is effective for 4 years. (5) Dieldrin is used like D.D.T. (6) Heptacholor, 1 to 5% in No. 2 fuel oil or in water emulsion, applied at the rate of 0.5 pint per square foot or 3.75 gallons per 10 cubic feet of soil, is effective for 4 years. (7) Penta 36 Panorama chlorophenol, 5% in No. 2 fuel oil applied at the rate of 7 gal lons per 10 cubic feet of soil. (8) Toxaphene, 5% of the ac tive ingredient in No. 2 fuel oil, applied at the rate of 1 pint per square foot of soil, has an effective duration of 6 years .(9) Trichlobrobenzene, a chemical diluted 1 part to 3 parts of No. 2 fuel oil (25% by volume) and applied at the rate of 5 gallons per 10 cubic feet of soil. All these chemicals are on the market under varying trade names. The customer must ex amine carefully the composition to determine the active ingre dient. Fuel oil is the best mat erial for suspension because it stays longer. Care should be exercised in handling these chemicals. Most of them are irritants and should not be allowed to come in con tact with the skin or the eyes. They should also be kept away from children and domestic ani mals. When treating the soil with these poisons, do not in clude areas intended for plant ing. Electrified Insecticide A METHOD of electrically charging insecticide and fungicide dust particles to make them adhere more thickly and firmly has been developed for the first time on a commercial scale by a United King dom firm, and incorporated in anew dusting machine. The revolutionary development is quite simple. The dust passes through a very high electrostatic field so that each individual particle acquires a positive charge. When the particle approaches the surface of the plant being treated, an equal and opposite charge is induced behind the plant, thus drawing the par * tide to it. As the object being sprayed now has a negative charge, the positively charged particle is hold to the surface. Because like forces repel each other, the dust particles are evenly distributed over the surface. At the same time the dusts are deposited in almost equal quantities on tha lower surfaces of leaves. It is estimated that total deposits obtained by by this new method of spraying are from four to ten times the amounts obtained by conventional means. November 1958 37
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