The Bulletin. 



11 



why a single tree should be lost if the grower will exercise the energy 

 necessary to treat them. 



The insects show a disposition to locate at the rings which mark 

 the end of a year's growth, and also around the buds. These two 

 places, therefore, should be watched in inspecting for it. The red 

 spots on the bark are not likely to be so conspicuous at these places 

 as they are on the clean areas of bark where there are no buds or 

 rings. Wood of from two to four years' growth is likely to be worst 

 infested. Hence we may say in a general way that in inspecting trees 

 which are suspected of being slightly infested, one should give special 

 attention to wood of from two to four years' growth and should ivatch 

 around the buds and'ycarly rings for the scales and should look for 

 the reddish spots on the clear areas of baric. It may often be more 

 readily found by the spots than by seeing the scale itself. If such 

 a spot be found, however, it must then be examined to see if it is 

 caused by a true scale-insect, for there are certain unimportant 

 diseases which may have a similar effect. If the gray circular scale 

 is found in the center of the spot, and if the scale is readily removed 

 by scraping gently with a knife-blade or with the finger-nail, then 

 you may be pretty sure that it is San Jose Scale, and should at once 

 send specimens to the Entomologist to find out for sure. 



Turn one of the scales over gently with the point of a pin or 

 knife-blade. If it is one of the large full-grown scales the insect may 

 as likely be dead as alive under it, for the scale often adheres long 

 after the insect is dead. If the insect is dead, the dried body will 

 likely be found as a thin yellowish-brown particle under the scale. 

 If the insect is alive it will be seen as a little yellow object slightly 

 egg-shaped, but more pointed at one end, and slightly fiattened. 



Fig. 5.— Adult female of San Jose Scale, without scale, very much enlarged. The Ions: whip- 

 lash-like object is the sucking-tube through which the sap is sucked from the tree. (After Howard 

 and Marlatt, U. S. Dept. Agr.). 



