290 



STATE BOARD OF AGRICULTURE. 



AFFECTIXG THE BAKK 



The Oyster-shell Bark-louse. {Mytilaspis pomonim.) 



The most common scale-insect of the apple, without doubt, is the oyster-shell 

 bark-louse. Althoucrh everywhere present, and sometimes quite conspicuous, it 

 most often attacks trees that for some reason are unhealthy and therefore poorly 

 fitted to support the extra drain put on them by the scale. A strong, healthy 

 tree ordinarily can bear the presence of a few of these insects without much 

 apparent injury, and they may be present for many years in small numbers 

 without their presence being detected. When the tree becomes sickly the scales 

 xill multiply and carry it down very rapidly. 



The scales of these insects are elongated, shaped something like oyster-shells, 

 with the cast skins at the smaller ends. They are brown in color, the scales 

 of the two sexes being similar in form. 



REMEDIES. 



When a tree shows many of these pests it usually indicates poor nutrition or 

 some other unhealthy condition. Give the tree a tonic in the form of fertilizers 

 and cultivation. Scrub with lye during the winter time. Ordinary lye from 

 wood ashes will do as well as anything. Use an old broom with the brush cut 

 short to make a good scrubbing brush, and if necessary, apply also one of the 

 sprays recommended for the San Jose scale in the winter time. These strong 

 mixtures will do injury if applied at any other time than when the trees are 

 dormant. 



Fig. 5. — Oyster-sh 11 Bsrk-louse, aftT Howard. U. S. Dept. of Agr. l)iv. of Entomology. 



The Eccentric Scale. (Aspidiotus ancylus.) 



Closely resembling the San Jose scale, but differing in some of the details, 

 is the eccentric scale, sometimes called Putnams' scale in honor of its discoverer. 

 The male scale in this case resembles that of the female in form and color, the 

 cast skin being at one side instead of at the center as in the case of the San Jose 

 species. The ring and nipple so conspicuous in the case of the San Jose scale, 

 are usually obscure in the eccentric scale. This species propagates by means 

 of eggs and rears but one l.rood a year It is not apt to multiply .so as to 



