682 Bulletin 83. 



Our stud}^ of this new pest has not progressed far enough to 

 enable us to present a complete account, but fortunately the work 

 has reached a stage when we can confidently recommend an effec- 

 tive method for checking the insect before another season opens. 

 We feel that the gravit}' of the situation demands that the fruit 

 growers be made acquainted at once with the facts already learned. 



THE INSECT'S APPEARANCE. 



Fortunately, the larger, conspicuous, brown, dead scale or shell 

 of the mature female insect is present on infested rees during the 

 whole year, thus enabling fruit growers to tell at any time wheth- 

 er the pest is in their orchards or not. The illustration on the 

 front of this bulletin shows many of these dead scales natural size 

 as they appear on the branches. They are very conspicuous ob- 

 jects, as the figure shows, and may be easily found and recogniz- 

 ed wherever they occur. They remind one of small halved peas 

 colored dark brown and stuck on the branches. Beneath these 

 dead scales the bark presents a white scar of the exact shape of 

 the outline of the scale; these spots remain white for a long time 

 after the scale is removed. 



In April and May the living female insects resemble the dead 

 scales shown in the figure on the tit e page, but they are soft to 

 the touch and often striped with yellow. In June, after egg-lay- 

 ing has ceased, they become firm, smoother, lose their yellow 

 markings, and are then simply a dark brown shell. If this shell 

 be then turned over, it will be found full of the minute white 

 eggs of the pest. After July 15, the dead scales contain noth- 

 ing but a white dust consisting of the empty egg shells. Although 

 these brown shell-like remains of the mother insect persist on the 

 branches throughout the season, or even for a year or more, they 

 are no longer a menace to the tree. They occur most numerously 

 on the undersides of the branches of the preceding one or two 

 year's growth. 



Should a fruit grower find these large dead brown scales one 

 half as thick on his plum trees as they are shown in the figure, he 

 may be quite sure that there is also an alarming crop of the 

 young scales now in hibernation in similar localities on the trees. 



