The hidden way of life and the destructive work of termites imperceptible at the first stages make it very difficult to combat these dangerous pests.
Reliable protection of buildings and structures requires expensive and time-consuming measures. In the tropical countries of Asia, Africa, Australia and America, where termites damage not only human structures, but also many plantation plantations, much is being spent on anti-thermal protection.
Since the beginning of this century, intensive work has been done to find the most effective ways to combat termites, and to date, many countries have accumulated a lot of experience, which is based on modern specialists using new, powerful drugs and termite-resistant building materials.
In our country, recommendations on the control of termites are available in the works of a number of entomologists who studied the biology of these insects. In addition, collective recommendations were published in separate brochures: “Instructions on the protection of wood structures from decay and termites in tropical and subtropical climate” (1965) and “Struggle against termites. Instruction on the counter-thermal construction of residential buildings, industrial and other structures and the struggle against termites in the buildings infected by them “(1962-1971). Unfortunately, these instructions and especially the scientific articles of specialists are not normative, but only recommendatory in nature and practically not applied in practice. The measures prescribed by them are in most cases borrowed from foreign literature and their effectiveness has not been sufficiently tested on our termites.
The information given below is also compilative, but is based on local conditions, ecology and the harm of specific types of termites. In this connection, the entire territory inhabited by termites in the USSR is divided into four unequal areas: Central Asia, southern Ukraine and Moldova, the Black Sea coast of the Caucasus and Vladivostok.
Central Asia . All four types of termites that inhabit the territory of Central Asia (A. ahngerianus, A. turkestanicus, A. rhizophagus, M. turkmenicus) live in underground nests, feeding on dry grassy and arboreal vegetation of deserts. The damage noted by some authors of live pasture and sand-resistant plants, as a rule, is of a secondary nature – termites eat shriveled stems, branches and roots. It is most closely connected with the root system of A. rhizophagus, which, however, does not multiply in large numbers. In general, damage by termites of pasture and forest protective vegetation does not reach economically significant scales and, obviously, does not require any protective measures.
In the gardens and parks sometimes there are termites in old trees. The tree is populated from the ground through a dying or damaged root system or over the surface of the trunk under the cover of an earth crust. In this case, termites gnaw dead dead parts of the trunk and roots. In this case, they can be regarded as secondary pests that accelerate the process of destruction of old trees. However, the degree of influence of termites on this process is not clear and premature disposal of such trees should not be recommended. The dried trees must be removed as soon as possible after the death with the stump of stumps, in order to deprive a rich source of feed that lives in the garden or park of the termites, allowing them to multiply extensively.
Significant damage is caused by termites to railway sleepers, pillars and other wooden parts and structures that are outside of human habitation. To protect such products, the most reliable and proven method is deep industrial impregnation of wood under pressure of coal tar oil in accordance with GOST 2770-74 or slate according to GOST 10835-67. Installation of wooden poles on concrete stepsons and replacement of wooden sleepers with reinforced concrete excludes damage by termites. For construction and ornamental wood, impregnation with copper-chrome salts is promising.
Significant harm in the Central Asian republics is caused by termites to residential buildings and industrial buildings. A survey conducted by specialists of the Institute of Zoology of the Academy of Sciences of the Turkmen SSR showed that in Ashgabat, Nebit Dag, Kazandzhik and other cities and towns of Turkmenistan, termites damage homes, administrative and other buildings. The houses that were built without a foundation, with the laying of walls on clay mortar, suffer the most. Termites also penetrate into houses standing on a brick foundation, through various cracks or wooden extensions.
Foreign experience in the fight against termites shows that the most reliable way to protect a building is by correctly designing and constructing it. Significantly high costs require the struggle with termites in the structure that has already been damaged by them.
In the construction of any building in order to protect it for a long period from damage, termites solve two tasks: the destruction of termites in the soil directly under the building and the avoidance of termites in the building from the surrounding soil. The solution of the first task in the construction of large buildings, under which a trench 1.5 m deep and more is excavated, is carried out in the production of excavations, when together with the excavation of the soil they are removed from the future building and the termites inhabiting it. In those cases when the soil is removed to a shallower depth or only the cultivated soil layer is removed, chemical treatment of the soil is necessary.
The treatment is carried out after the construction of the foundation and internal supports, cleaning of construction debris and leveling the soil. Applied aqueous emulsions of potent and long-lasting toxicity in the soil of organochlorine insecticides: aldrin, dieldrin and heptachlor in a concentration of 0.5% at a rate of 5-6 l / m 2. According to the Southern Forest Experimental Station in Gulfport (USA), the use of these insecticides against termites of Reticulitermes flavipes was effective for 14-18 years after soil treatment. If, during the construction of the house, a layer of sand is poured onto the ground from above, it is treated in the same way. The methods of soil treatment with solutions of sodium pentachlorophenolate or pentachlorophenol proposed in the “Instruction on counter-thermal construction …” (1971) are less effective and may not lead to the complete elimination of termites. Recommended by Kakaliev (1972), chlorophos and sevyn are toxic enough for termites, but they decompose very rapidly in the soil and can not serve as a barrier to termites in the future. Chlororganic drugs, although they have a number of limitations due to harmful effects on the human body, While still the most effective for the destruction of termites in the soil. When working with them in construction, all precautions should be followed, as well as the pollution of surrounding vegetation and soil. In the closed underground of the house they should not be in contact with human food. In this connection it is inadmissible to use the underground for economic purposes. To prevent the tenants, it is desirable to make large warning signs on the inside of the foundation: “The soil is etched with pesticide, October, 1975. Do not dig!” In this connection it is inadmissible to use the underground for economic purposes. To prevent the tenants, it is desirable to make large warning signs on the inside of the foundation: “The soil is etched with pesticide, October, 1975. Do not dig!” In this connection it is inadmissible to use the underground for economic purposes. To prevent the tenants, it is desirable to make large warning signs on the inside of the foundation: “The soil is etched with pesticide, October, 1975. Do not dig!”
The second task of building a terminal-protected building – the avoidance of termites from the surrounding soil – is solved using a set of constructive measures. The building is built on a stone foundation and supports with a high base made of baked brick or stone in a complex mortar with high-quality cement or a rough reinforced concrete foundation laid on insecticide-primed soil.
As a mandatory element of protection, all the literature sources mentioned also recommend the pickling of soil around the building with various insecticides. This work is more convenient to carry out immediately after the erection of the socle. First, abundantly spray the outer wall of the foundation and excavated trench around it, then fill it with treated soil and after sealing around the base make a concrete or asphalt ebb. The details of this operation in application to Central Asian termites do not yet have sufficient justification. In particular, the necessary and sufficient dimensions of the trench have not been established. The depth of the trench recommended by Kakaliev (1972) of 80 cm and width of 1 m is probably a reliable barrier against termites, but it is possible that its dimensions can be reduced without reducing reliability. The same applies to the width of the concrete outflow around the building,
Insecticide-etched soil, hidden under concrete tint, retains a protective effect for many years, but gradually its toxic properties are reduced. Therefore, in 10-12 years after the construction, it is necessary to additionally etch the ground under the ebb and flow around the building. This operation is carried out simultaneously with the replacement of the ebb, if it has numerous cracks. If the ebb tide is at this time in good condition, then a series of holes are drilled in it and through them an insecticide is injected into the ground with the help of an injector. This preventive treatment guarantees, under all sanitary norms and rules, the protection of the building for many years from the access of termites.
Destruction of termites in the structures they infested presents the greatest difficulties. At the same time, there are no reliable methods for exterminating the termites in houses built from raw brick, without a foundation and with an earthen roof (a local type of rural buildings in Turkmenistan). All the recommended measures can only temporarily reduce the number of insects in the house.
In houses built on a stone foundation, the struggle against termites should be timed to repair the building. In this case, the same tasks are solved as in the construction of a lady: the destruction of termites in the soil under the house and the avoidance of termites in the building from the surrounding soil.
To destroy the termites after the opening of the floor along the inner perimeter of the foundation and around the supports, dig a trench up to 1 m deep or the entire depth of the basement, if it is smaller. The foundation and supports are sprinkled with insecticides. The removed soil after spraying and thorough mixing is again placed in a trench. Ground in the underground after cleaning from any garbage is leveled and processed as during the construction of the house.
To prevent termites from entering the building, the outer side of the foundation and the docking are plastered using high-quality cement and around the whole building a screen is made of etched soil with a concrete or asphalt casting device, as in new construction. In some cases, if the lower parts of the walls of the house or the basement are to be repaired or replaced, it is useful to install protective metal visors.
In the “Instruction on Counterterm Construction …” (1971), after these operations, the processing of wooden structures of buildings with the purpose of destroying termites in them is prescribed as “one of the most difficult and important” works. This work requires high skill of the performers and even thus often gives dubious results, since insecticides do not penetrate into the depth of wooden parts where termites can be found, and insects do not die after processing.
Given the complexity and low efficiency of such processing, we believe that in Central Asia it can be abandoned altogether, performing carefully all the other operations described above. Since all Central Asian termites are soil, that is, they have nests in the soil, and the timber of buildings is used as a source of food, the termite workers that are left in the nest and remain in the wooden parts of the building will not be able to reproduce further. Soil these termites are also used to replenish moisture reserves. Termites deprived of this possibility will not be able to survive in the building for a long period and will die without the use of chemical preparations.
In the same cases, when there is an urgent need to eliminate termites in the building, fumigation with fluoride-sulfur gas, which is widely used in the USA for the destruction of termohole termites, is most effective.
Southern Ukraine and Moldova . In this area there is only a light-colored termite (R. lucifugus), classified according to the ecological classification to termites of moist wood. Termites in the south of Ukraine and Moldova, in contrast to the termites of Central Asia, are not overspent, but occur in separate foci. Therefore, in the complex of protective measures, it is important to conduct surveys of settlements and plantations in order to identify foci of termites.
Termite damage to the old roots of grapes was noted at the end of the last century.
Usually they settle in old stems with dying wood, which they feed on. Although these damages are never of a mass character, termites in some cases accelerate the death of bushes, which justifies the use of chemical treatments. Since phylloxera is one of the main pests of grapes in these areas, the struggle against termites is conveniently combined with seeding the root form of this pest.
One of the most effective methods of killing phylloxera is etching soil hexachlor with butadiene. This drug is effective against a large Caspian termite. Experimental data on the effect of hexachlorobutadiene and the necessary dosages for the light-cautious termite are not available in the literature known to us. Obviously, this issue is still waiting for its researchers.
A long-term hotbed of termites is known in the Odessa Botanical Garden, where termites damage wooden parts of greenhouses year after year. In recent years, wooden parabni greenhouses replaced by concrete, which significantly reduces the harmful activity of termites.
Repeatedly observed in the literature are cases of severe destruction of wooden building elements in the Odessa, Kherson and Nikolaev regions.
In these areas it is necessary to conduct a detailed survey of settlements on termite contamination. With new construction in the outbreaks of termites, all preventive measures should be followed, especially those elaborated in the American literature on the basis of many years of experience in the control of termites of the genus Reticulitermes.
In addition to the measures described above for Central Asian termites, it is necessary to take into account the association of the photophobic termite to moist soil. In this regard, in damp places it is recommended to conduct drainage works around the building, ensure good ventilation of the underground and cover the ground under the house with waterproofing material. All these measures simultaneously protect the building from damage by mushrooms. When protecting a building from a light-cured termite, it is necessary to take into account the small size of these insects and especially carefully seal all cracks and cracks in the lower part of the house.
Preventive measures in buildings in operation include periodic surveys of contamination with termites, keeping the cellars clean and surrounding the building of the territory, maintaining in the basement part of the building and the ebb (timely repair during cracking and deformation).
Destruction of termites in the structures infected by them is carried out in the same way as described above for the Central Asian termites. Additionally, drainage works are carried out, as in the construction of new houses.
Light-fluffy termite, like the Central Asian species, refers to soil termites. But it’s much quicker and easier to form additional sex individuals and isolated parts of the family that are inside the house in wood trash, especially in combination with tree rot, in wet seaside areas can exist for some time in isolation from the soil and even multiply, continuing to destroy the wooden elements building. Therefore, with regard to this termite, it is necessary to conduct extremely labor-intensive fighter operations inside the building.
Black Sea coast of the Caucasus . Living in the Black Sea coast of the Caucasus, the only one in our fauna of the representative of the termotyled termites Kalotermes flavicollis, fortunately, is still not marked as a serious pest. In the city of Sukhumi it is sometimes found in parkland plantations, but settles in the dead parts of the tree and, feeding on dead wood, manifests itself only as a passive secondary pest. As a result of the activity of this termite, the formation of duples in old trees and their dying off are accelerated.
As preventive measures to prevent the settling of this termite, it is necessary to conduct timely and correct pruning of dry branches with the coating of sections with garden putty and sealing of valuable trees with cement mortar. The dead trees and stumps should be removed in a timely manner. Termite is not marked in yellow-cheek houses.
Vladivostok . Discovered in 1969 in residential houses in Vladivostok, the term Reticulitermes speratus proved to be a dangerous pest. It severely damages the wooden floors, walls and other elements of residential and public buildings in the city center. Probably R. speratus was brought to Vladivostok several decades ago from Japan or China. In nature near the city and other areas of Primorye, termites have not yet been discovered, but their long-term preservation in the remains of demolished houses and in outbuildings without any heating creates real preconditions for their acclimatization, which greatly increases the danger of this pest.
Numerous cases of importation and acclimatization of termites in new areas outside their range have been described in the literature. The American termite Reticulitermes flavipes, brought to Hamburg more than half a century ago, is very notorious and still damages residential and administrative buildings there, despite repeated attempts to destroy it.
The impossibility of applying a planned and radical struggle against termites in a capitalist port city should serve as a good lesson for us, and a vivid example of significant economic damage is an additional incentive for the proper and timely organization of radical and planned measures to eliminate a relatively small foci of termites.
The first step in this direction should be considered the organization in Vladivostok of a permanent inspection service for the inspection of urban structures for infection with termites. So far, only one focus has been identified in the Frunzensky district, covering about thirty houses. However, it is quite possible that the hidden harmful activity of these insects will be found in other parts of the old city and its suburbs.
Currently, there is a planned reconstruction of the city center, which is already partially implemented. Many old houses are demolished, and in their place are built capital multi-storey buildings. Work on the reconstruction of areas contaminated with termites should be carried out in compliance with all precautions, so as not to endure termites outside the hearth. In particular, it is impossible to allow the export of furniture and building materials contaminated with termites by residents; All the wooden details of the houses and outbuildings in question must be burned in place, the construction debris and soil should be treated with poisonous chemicals and taken out of the city.
When constructing new houses in Vladivostok, special attention should be paid to the waterproofing of the building and the ventilation of the cellars.
Conducting fighter operations in termite-contaminated pre-revolutionary buildings is obviously impractical. In the same cases, when the building is to be preserved, all the work required for light-sensitive and other termites of the genus Reticulitermes should be carried out.
The task of eliminating the foci of termites in Vladivostok will not be fully resolved if strict quarantine control is not applied to these insects. Now, with significant expansion of trade with Japan and other countries of Southeast Asia, this control is especially important.
Despite the complexity of termite control and significant financial costs, the focus should be on organizational arrangements. Attracting due attention to this issue of the city administration with the active assistance of the population will undoubtedly make it possible to completely eliminate Vladivostok hotbed of termites. What was not possible in capitalist Hamburg, must be successfully carried out in Vladivostok.