150 Report of State Board of Horticulture. 



Probably a considerable number of larvae pupate under clods and rub- 

 bish on the ground. 



Birds are the most effective natural aids in controlling the codling 

 moth. No benefit is to be expected from the introduction of foreign birds 

 or from artificial use of fungous and bacterial diseases. 



Spraying with one of the arsenites is the most practical method of pro- 

 tecting fruit from the codling moth. It is not only practical but necessary 

 to spray for the second brood. Persistent, intelligent spraying should 

 give eighty-five to ninety per cent of fi'uit free from worms. Our best 

 orchardists do even better. 



Clean, smooth trees, clean cultivation, sheep or hogs in the orchard, 

 screens over the doors and windows of storerooms, and banding the trees 

 are efficient supplements to spraying. 



EXPERIMENTS WITH INSECTICIDES FOR 



THE SAN JOSE SCALE. 



By Prof. S. A. Forbes, State Entomologist, Urbana, Ills. 



The "California wash" of lime, sulphur, and salt, and the "Oregon wash" 

 of lime, sulphur, and blue vitriol have been for many years the general 

 reliance of the fruit growers of the Pacific Coast for protection against 

 the San Jose scale. In a letter to me, dated October 22, 1901, Prof. C. W. 

 Woodworth, of the entomological department of the University of Cali- 

 fornia, said that "the lime, salt, and sulphur mixture is the sole dependence 

 in this state for killing the San Jose scale"; and under the same date 

 Prof. A. B. Cordley, of the entomological department of the Oregon Agri- 

 cultural College and experiment station, wrote: "With us the lime, salt, 

 and sulphur compound is a very satisfactory remedy for the San Jose 

 scale, and is used very extensively. In fact, this and the lime, sulphur, 

 and blue vitriol compound are practically the only ones used for winter 

 sprays for this insect." As early as 1889 the California wash was the 

 only winter remedy recommended for the San Jose scale by the secre- 

 tary of the state board of horticulture, in the annual report of the board 

 for that year; and in 1896 Prof. John B. Smith, state entomologist of New 

 Jersey, who visited California for a special study of the San Jose scale and 

 its treatment there, found the lime salt, and sulphur mixture one of the 

 "favorite insecticides" for that scale in California and on the Pacific 

 Coast generally.* 



The introduction of these insecticides in the East has been long de- 

 layed, probably owing in large measure to unfavorable reports of experi- 

 ments made in the Atlantic states. In articles published in Bulletin 3 of 

 the United States division of entomology, issued in 1896, and in Bulletin 

 30 of the same series, 1901, p. 34, the reported failure of the California 



*Rep. Ent. Dept. N. J. Agr. Exper. Station, 1896, p. 551. 



