582 



STATE BOARD OF AGRICULTURE. 



While by no means to be compared with the San Jose" scale in destruc- 

 tiveness, it sometimes becomes numerous enough on small trees to do 

 serious injury. It readily succumbs to the caustic and soap washes used 

 against most of the scales. 



THE PLUM SCALE. 



(Lecanium cerasifex Pitch.) 



During the past year several specimens of a scale-insect on cultivated 

 plum have been received. These are undoubtedly the New York plum- 

 scale (Lecanium cerasifex Fitch), which has been the cause of a great 

 deal of loss in the eastern states. The scales (Fig. 11) are brown, hemis- 



Fi< . 11. Plum Scale {Lecanium cerasifex) (after Slingerland). 



pherical bodies about one-eight of an inch in length and with a dark 

 brown, shiny surface, sometimes slightly wrinkled transversely. The 

 longest diameter of the scale is usually placed lengthwise of the twig. 

 During the early summer these scales are soft and easily crushed into a 

 mass of pulpy flesh, but by the middle of June they become hard shells of 

 a papery or horny texture and are then nearly full of eggs, which have 

 been laid by the mother insect under her own body. The number of eggs 

 under each scale is estimated at between one and two thousand. Dur- 

 ing July the tiny lice which emerge from the eggs make their way to 

 the under side of the leaves, where they at once commence to suck the 

 sap. Here they remain until late in August, when they migrate to the 

 twigs, where they pass the winter. In this stage they are soft-bodied and 

 less protected than at almost any other stage in their existence. Only 

 one brood is batched during the year. 



