FOOD PLANTS. 



The San Jose Scale has been found on about 125 different kinds 

 of trees, shrubs and vines. On many of these it will hardly more 

 than exist and the chief danger in those cases is that such plants 

 may serve as places from which to pass to others where it would be 

 more destructive. Nearly all our fruit trees, however, are liable to 

 destruction by this pest. It seems to cause the greatest injury in 

 Massachusetts to the pear, plum, apple, peach, some varieties of 

 cherry, and currant. Among ornamental shrubs and trees the Dog- 

 woods, particularly the Red Osier, the Hawthorne and other thorns, 

 the Japan Quince, poplars, ornamental cherries, plums and currants, 

 roses. Mountain Ash, willows, the Hop tree and some kinds of Spiraea 

 are often killed by it. This list includes almost all our fruit trees 

 and more common ornamental shrubs and if to it we add those on 

 which this pest will live and menace the more susceptible plants, it 

 will be at once seen that the situation in Massachusetts is certainly a 

 dangerous one. On fruit it produces unsightly discoloration, reduc- 

 ing its selling value. This condition was very noticeable on the fruit 

 exhibits at fairs in the fall of 1906 and much of the fruit for sale in 

 our markets shows the marks of the scale. 



ENEMIES OF THE SCALE. 



Several kinds of minute insects are parasitic on the scale, and a 

 fungus lives upon it, but none of these appear to accomplish much 

 in Massachusetts, the most effective foes here being a very small 

 black beetle, Microweisea misella (Lee), and a larger one, also black, 

 but with two red spots on its back, these spots having given to the 

 insect the name " Twice-Stabbed Lady Bug." These two beetles 

 are active enemies of the scale but are not sufficiently abundant to 

 hold it in check. 



In its native country the San Jose Scale appears to be kept under 

 control, as already stated, according to investigations made by the 

 United States Department of Agriculture, by a lady bug very similar 

 in appearance to our " Twice-Stabbed Lady Bug," and colonies of 

 these insects have been brought to this country in the hope that they 

 might accomplish similar results here. It is too soon to deter- 

 mine the success of this experiment, but thus far the results are 

 not encouraging, particularly in the more northern states, like 

 Massachusetts. 



