N.). 6. DRPAHTiMKNT OF AGRICULTURE. 507 



The reasous this pest is so injurious are, first, that it attacks all 

 kinds of liuit trees, many kinds of ornamental shrubbery and even 

 some of our shade trees and forest trees. In sayinj^ that it attacks 

 all kinds of fruit trees, however, we do not wish to be misleading 

 and give the inference that it is equally injurious to all varieties. 

 Some, such as the Kieffer pear and certain varieties of plums and 

 cherries are not seriously injured by it. Others are more readily 

 killed. It will destroy a tree in from one to five years. We have 

 known of its existence upon currant bushes which bore fruit in June 

 and were killed at the following September. A mere list of the 

 plants which it attacks would not be of great usefulness because 

 these attacks are in different degrees of severity upon different kinds 

 of plants. For example, the Osage orange is decidedly injured and 

 quickly killed by it, while the California privet is only slightly 

 attacked. Thus to say in a mere list that it is found on both these 

 plants would be misleading, and yet true. It attacks grape, but 

 not to a very injurious extent, and may also be found to a slight 

 degree upon soft maple, mulberry, elm and certain willows as well 

 as other woody plants. It is particularly injurious to peach, apple, 

 pear, quince, some varieties of plums and a few of cherries. We 

 hope to publish a carefully prepared list giving the relative degrees 

 of immunity of different plants attacked by it and this will be for 

 free distribution as one of our monthly bulletins of the Division of 

 Zoology of the Department of Agriculture. I would call the atten- 

 tion of the Board to the fact that these bulletins are published 

 monthly from the office of the Zoologist and are free for all persons 

 who desire them. The}- are making a special feature of the San 

 Josd Scale and the practical remedies for it, and in the bulletin for 

 November, 1903, maj' be found a discussion of its habits, means 

 of distribution and remedies given in such detail that anyone can 

 use this with success. 



Second, another reason that this pest is so injurious is that it 

 is so minute and iuconsjiicuous; it is not as large as the head of a 

 common dressing pin, and is not of a conspicuous coloration. It 

 often exists upon trees until the latter are killed and even then 

 the presence of the San Jos(^ Scale is not suspected but it is thought 

 that the tree has died of some fungous disease. 



Third, another reason that it is so injurious is that it is very 

 prolific. A single female becomes the ancestor of over three billion 

 living young in one year's time. This figure is published by Pro- 

 fessor Forbes, of Illinois, one of the greatest entomologists of the 

 country. 



Fourth, another reason that it is so injurious is that it is suctorial 

 in its method of feeding and injects a i)oison into the inner bark 

 of the tree, upon which it is found, similar to the manner in which 



