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THE AGKICULTURAL NEWS. 



August 26, 1916. 



INSECT NOTES. 



ON THE DAMAGE DONE BY TERMITES 

 OR WHITE ANTS. 



The termites or so-called white ants, or wood-ants, are 

 not true ants, but get their name from the .similarity of their 

 social organizations to those of the true, ants in the Order 

 Hymenoptera. In their structure and life-history they more 

 nearly resemble such insects as the pond-flies and the lace- 

 wing flies. They live in large colonies, which generally have 

 an extensive central nest containing one or more fertile 

 egg-laying queens, and enormous numbers of workers. 

 These queens attain a size much larger than any of the 

 workers, because of the enormous distention of the abdomen 

 which results from the development of tlie organs connected 

 with egg-laying. 



These insects are nearly always blind, and they hide 

 from the light When it is necessary to cross an exposed 

 surface, they build tunnels or covered galleries, through 

 which they travel from place to place. They feed upon 

 wood, and are able to excavate timbers and lumber used in 

 construction, to such an extent as to render them entirely 

 worthless. They often attack picture frames, chairs, tables, 

 and other furniture, especially in old hou.ses where these 

 articles come into contact with the walls, or where they are 

 not often moved. 



Wood-ants are very difficult to control when they have 

 become establi.shed in or about buildings. The nests can some- 

 times be located, and if these can be thoroughly destroyed, 

 the numbers of the ants can be greatly reduced. These nests 

 are often to be seen as irregular woody masses on the trunks 

 of trees, and where they are thus found they may be cut 

 down and removed. Domestic fowls and turkeys are very 

 fond of these insects, and will eagerly eat them if the nests 

 are broken up so that they are exposed. Sometimts, 

 however, no nests can be found; but if any of their galleries 

 can be located, many of the ants can be killed by means of 

 poisons. A mixture of arsenic and .sugar, or strychnine and 

 sugar can be put down in these galleries as a poison bait. 

 The insects which are killed by this are eaten by other insects 

 in the nest and the poison becomes widely distributed. A 

 mixture of oak or spruce .sawdust and cither of the poisons 

 mentioned may also be used as a bait. If a small box 

 containing this ipixturc is placed in a building where wood- 

 ants are known to occur, and it is kept .slightly moist, they 

 ■will probably find it and will feed upon it. Sawdust or 

 sheep manure in boxes, barrels, or bags, left standing on 

 the ground for some time, is attacked by wood-ants. This 

 fact suggests the po.ssibility of successfully using poi.son baits 

 in this manner. 



In the Agricultural News, Vol. XIII, X'l. 321, for 

 August 15, 1911, the damage causetl by termites to sugar- 

 cane in St. Kitts was referred to. There is principally one 

 species which is now known to be Leucotermes tenuis, which 

 is a South American insect. This termite does not build 

 any nest or covered galleries either in St. Kitts, or in 



Barbados, where it has also been under observation. These 

 insects attack sugar-cane cuttings newly planted in the field, 

 often completely destroying them They may also attack 

 the ripening cane which they sometimes completely destroy 

 over considerable areas. The remedy to employ for this pest 

 consists in the complete destruction of all termite-infested 

 material in the cane fields, the exercise of great care in plant- 

 ing only cuttings quite free from termite.?, and by rotation of 

 crops. In Antigua, and sometimes also in St. Kitts, another 

 species of termites attacked sugarcane fields. This is 

 H'utermes haitiensis, an insect which builds a large rounded 

 nest and covereil galleries through which the individuals 

 travel. A remedial measure to be adopted in this icstance is 

 the destruction by burning of all their nests wherever found, 

 and all infested pieces of canes occurring in the fields after the 

 crop has been harvested. 



The United States Department of Agriculture (Bureau 

 of Entomology) has just issued a Bulletin (No. '.V33) dealing 

 wich termites in the United States, their damage, and methods 

 of prevention. In regard to plants, reference is made to the 

 damage which this pest can do to corn, the stem of this plant 

 being frequently hollowed out. This damage has been 

 observed frequently in the Southern States. Cotton has also 

 been observed injured by termites, the insect destroying the 

 stem about 2 inches below the surface of the soil, a hole being 

 bored through the stem and into the heart of the plant. 



The principal kind of damage, however, cau.sed by 

 termites, to which this Bulletin gives attention, has reference 

 to woodwork in buildings, etc. In preventing this damage it 

 is stated that the main point is to prevent the insect from 

 gaining access to the woodwork from colonies in the ground, 

 either by means of substituting rock or concrete foundations, 

 and concrete or pile flooring in the basement, or by j)rotecting 

 the foundation timbers in contact with the ground by 

 impregnation of the wood with coal-tar creosote. It is pointed 

 out that it is very rarely possible to find and destroy the 

 external colony, and it may be necessary to replace the 

 foundation of the building with walls and Hooring of stones, 

 concrete, or other form of rock composition, and this is 

 the most permanent and complete preventive. If the 

 foundation of the building is .such that damage to the wood- 

 work is extensive and likely to recur, and it is impracticable 

 to replace it with concrete or stone, it is advisable to replace 

 the exposed interior woodwork with wood impregnated by a 

 6 per cent, solution of zinc chloride, or a 1 per cent, solution 

 of bi-chloride of mercury; except in case of flooring in 

 contact witji the ground or in wet situations, where such 

 preventive would leach out. In some cases thorough and 

 repeated drenching of infested timbers, where accessible, with 

 kero.sene oil may artbrd temporary relief and kill .some 

 of the termites. Kerosene oil should be poured into the 

 crevices through which the winged insects emerge from 

 infested wood. As the insects may have entered the h'Hise 

 through soil channels by means of pillars dt the supports of 

 perches and steps, these last should be removed if damaged, 

 and the ground soaked with kcro.sene. 



A Pest of the Orange Tree.— The occurrence 



of a pest causing injury to oranges in Brazil is recorded 

 in the Hevieiv of Applied Entomology, Series A: Agricultural, 

 Part VI, p. 2(11. This pest is a moth which appears to be 

 very similar in its habits to the one which has been reported 

 on oranges in Dominica (.see Agricultwul A'tw.s, Vol. XII, 

 No. 302, November 22, 1913). 



