These are the greatest enemies on the cotton plantations, and the same remedies are effectual in both. The natural enemies of the cotton worms are numerous and abound in pro portion as the worms are abundant. Certain kinds of ants are most efficacious in reducing their numbers, as well as ground beetles, bugs and idineutnon flies (q.v.). The general and most practical remedies against this trouble some pest are the insecticides, especially Paris green and kerosene emulsions. The dry prep aration is one pound of the green to from 20 to 35 pounds of cheap flour, or, instead of flour, land plaster (gypsum) or cotton-seed meal. The best preparation of Paris green consists of one pound to 40 gallons of water. London pur ple may be applied dry, using two pounds to 18 of flour, etc.; or wet, one-half a pound to 50 or 55 gallons of water.
A fine spray of kerosene oil applied to the leaves will kill all the worms in a remarkably short time, but as petroleum in any form in jures the plant, the oil must be so diluted as to injure only the worm and not affect the plant. The use of milk as a diluent has been suggested.
In recent years the pink cotton boll-worm, long a pest in Egypt, has invaded the United States via Mexico, where it got a footing in 1911, In the latter country it is destroying • from 50 to 75 per cent of the crop. It reached the country in two shipments of Egyptian cot ton seed. Every lot of seed contained the eggs of the pink boll-worm, and in two years the pest had spread throughout Mexico. It is also
present in about 3,000 acres of cotton land in Galveston and Harrison counties, Tex., where the State and Federal governments are now engaged in its extermination. The Congress ap propriated $500,000 for the work. The method of extermination is radical. First the cotton stalks in the entire field are cut by a machine which covers about 22 acres per day. Then a rake goes over the field and places the stalks in rough piles. Next come handworkers who gather each little boll and piece of cotton and all other vegetation and put it on the pile. The whole is then burned, leaving a field cleared utterly of all vegetable and animal life. The moth which is the parent of the pink boll-worm is fragile and can fly no great distance. It is chiefly in the seed that it is transported, and the eggs can exist there for months. The worm damages the crop in many ways. In the field bolls fall to the ground and 50 per cent of the crop may be lost in this way. The grade of cotton is also damaged and the insect stains what cotton is produced. In addition oil pro duction is lessened and the cotton seed is rendered unfit for planting and germinates poorly. Consult Journal of Agricultural Re search for 4 June 1917, issued by the United States government; also Riley, 'Report IV> of the United States Entomological Commis sion (1885) ; and Bulletin 18 of the Entomologi cal Division of the United States Department of Agriculture (1898). For cotton-boll weevil, see WEEVIL.