American Bulletins on Agricultural Subjects

Abstract

THE results of the investigations carried out at the American experiment stations are issued as bulletins, and are sent out broadcast to all who are interested. Perhaps none of the institutions is more prolific than the Bureau of Entomology of the United States Department of Agriculture. In bulletin 97, part iv., Dudley Moulton describes the Californian peach borer (Sanninoldea opalescens, Hy. Edw.), which has been a constant menace to fruit-growers in certain districts. The adult moths fly from June to October, but are present in maximum numbers during July and August. The eggs are placed immediately after emerging, and after about two weeks the newly hatched larva? enter the tree. The protective wash, a mixture of lime and tar oil, must therefore be applied before the middle of June. Carbon disulphide is used to a certain extent as an insecticide, but it has obvious disadvantages in that it is very volatile and combustible. Attempts have from time to time been made to replace it by a less dangerous liquid, and in bulletin 96 Messrs. Chittenden and Popenoe discuss the relative advantages of carbon tetrachloride and carbon disulphide as insecticides. It appears that the tetrachloride is less efficient and far more expensive, so that the problem is not as yet solved.