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COTTONY MAPLE SCALE 

 {Pulvinai-ia innumerabilis Rathv.) 



This scale insect is frequently a very serious enemy of soft maples 

 and is often present in smaller numbers on other maples, elms and 

 other plants. It is found on twigs and looks like a small mass of 

 cotton, protruding at one end from beneath a brown scale. 



During the spring months before the cottony portion has devel- 

 oped, this insect is not very noticeable, but by the end of June and 

 during the two months following the cottony threads among which 

 the eggs and young are found, make it a prominent object. 



The young soon leave the cotton where they were born and wan- 

 der to the leaves where they settle down, generally along the veins, 

 and each secretes a covering scale. Shortly before the leaves fall 

 they migrate from them to the twigs, where they spend the winter. 

 In the spring they grow rapidly and produce large quantities of 

 honey dew, which adheres to and dries on the leaves or twigs on 

 which it may fall. In June the cottony threads are produced and 

 the insect then becomes more noticeable. 



Brushing the infested limbs and twigs with a stiff brush wet with 

 kerosene emulsion has been recommended as a treatment for this 

 insect. The most successful results, however, have been obtained 

 b}" winter spraying with eighteen to twenty per cent, kerosene emul- 

 sion. This may be made by mixing three gallons of the stock emul- 

 sion (see directions for making at the end of this article) with about 

 seven and a half gallons of water. 



BORERS. 



Almost every kind of tree and shrub seems to be attacked by 

 borers, and as their work is inside the stem to such a large extent, 

 successful treatment is often very difficult. As it is impossible to 

 consider the different borers separately here, a few general sugges- 

 tions are all which can be given on this subject. 



In nearly all cases, the eggs of the borers which work in the 

 trunks are laid on the bark. Accordingly, anything covering the bark 

 which will prevent egg laying without injuring the tree will be useful 

 if applied at the proper time. Sometimes, soaping the trunk for this 

 purpose is of value ; whitewashing the trunk frequently induces the 



