206 Forty-ninth Report on the State Museum 



which it is believed to have passed from the plum, its life-history, its nat- 

 ural enemies, and approved methods for combating it. 



This scale, has been found abundantly in some localities in Eastern, 

 New York ; in Orange county, it has been mistaken by some fruit-growers 

 for the San Jose scale, but from their great dissimilarity in appearance^ 

 there is hardly an excuse for confounding them. 



The figure representing an infested plum branch is from a photograph 

 taken by the Geneva Experiment Station, and employed in illustrating a 

 brief notice of the insect by Prof. S. A. Beach, in Garde?i and Forest for 

 July i8, 1894, from which paper it has been obtained. 



In the preceding brief notices of some of our more common scale in- 

 sects, particular mention of the insecticides available for their destruction 

 and methods of application, have been omitted, as those which will be 

 indicated for use against the San Jose scale, will be found equally service- 

 able against each one of them. 



The San Jose Scale. 



The San Jose Scale — from the many different fruit trees that it infests, 

 the rapidity of its multiplication through its successive broods during the 

 year, and the short time in which it kills the trees that it attacks — is 

 justly regarded as one of our most peinicious scale-insects. Its character 

 is indicated in the specific name oi peiiiiciosus given to it by Prof. Corn- 

 stock when first described by him in 1880, in the Report of the Commis- 

 sioner of Agriculture for that year. He has written of it: "It is said to 

 infest all the deciduous fruits grown in California, excepting peach, 

 apricot, and the black Tartarean cherry.* It attacks the bark of the 

 trimk and limbs as well as the leaves and fruit. I have seen many plum 

 and apple trees upon which all the fruit was so badly infested that it was 

 unmarketable. In other instances I have seen the bark of all of the 

 small limbs completely covered by the scales. I think that it is the most 

 pernicious scale-insect known in this country." 



The Los Angeles (Cal.) Horticultural Commission, in their report for 

 1893, say of it: -'This pest, if not speedily destroyed, will utterly ruin 

 the deciduous fruit interests of this coast. It not only checks the growth 

 of the tree, but it covers the tree literally entirely, and the fruit nearly as 

 much so, and, if left unchecked, the tree is killed in three years' time." 



*It has since been found on the peach and apricot. 



