The Bulletin. 



17 



or spend liours in a friiiLlcss search fur it un ilie forest or shade trees, 

 and then, wlien tliey tind a scale (which is some other species in nine 

 cases out of ten) they think that they have surely found it. 



Let us repeat, then, with gi-eater emphasis, that the 8an Jose 

 Scale is primarily a pest of orchard fruit trees; it may also occur, 

 hut less frequently, on rose, grape, currant, gooseberry, mock-orange, 

 arid Japan ivalnut, hut forest wnd shade trees are not appreciable' 

 factors in harboring or spreading it. 



HOW LONG BEFORE IT KILLS THE TREE? 



The answer to this question will depend upon the kind of tree and 

 the age at which it first becomes infested. Let us take some different 

 examples: 1. If the tree becomes infested as soon as budded, peach 

 and plum are likely to die within from one to two years ; apple, pear 

 and cherry in from two to four years. 2. If they become infested 

 when five years of age, peach and plum will usually die in three or 

 four years, pear in four or five years, and cherry and apple in four 

 to six years, or perhaps not at all. 3. If they become infested at the 

 age of eight years or over, our observation has been that apples are 

 not likely to be killed outright, though peaches, plums and pears 

 may be. Of course, an infested tree should be regularly and thor- 



FlG. 7.— Pitiful Lady-beetle. Below are shown the adult at a, the larva at 6 and the pupa at c, 

 all much enlarged, the actual size indicated by a small line close by. 



Above is shown a number of the insects feeding on the San Jose Scale in the blossom end of 

 pear, also enlarged. (After Howard and Marlatt, U. S. Dept. Agr.). 



