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CEMENT PAINT 



Portland cement, skimmed milk. Add enough milk to reduce the 

 cement to the consistency of thick paint. 



Either of these two applications should be painted on the trunk and 

 larger branches as far up as the insects are likely to attack, usually ten 

 or twelve feet. If the bark is rough and scaly it should be smoothed off 

 first. Cement paint is good for one whole season, but whitewash should 

 be applied twice during the growing season for best results. 



It is very difficult to eliminate borers once they have obtained a foot- 

 hold. The individual boring holes must be probed with wires or sat- 

 urated with carbon bisulphide (high life) squirted in with an oil can, 

 after which the hole must be plugged up with clay, putty, or some other 

 handy material. The third alternative is the obvious one of gouging 

 out the holes until the worm is found and killed. 



Wood borers are found boring through the heart and sap wood of 

 healthy, dead, and dying trees. They are only slightly less dangerous 

 than bark beetles, causing the death of many large veteran trees and 

 often weakening the limbs of others so much that they are readily broken 

 off in a heavy wind. They may be controlled to some extent by the 

 same means that are used against bark borers, mentioned above. 



Defoliating insects are easy to control but if left unmolested the strip- 

 ping of the leaves will seriously weaken the tree. Three successive de- 

 foliations will usually kill a deciduous tree, while one complete defolia- 

 tion may kill coniferous evergreens, which are not very resistant to the 

 attacks of these insects. 



It is sometimes practical to creosote egg-clusters or to collect the nests 

 and burn them, but the usual way to attack this class of insects is to 

 spray the foliage on which it feeds with arsenate of lead, which can be 

 procured in any town. Two and one-half pounds of poison to forty 

 gallons of water is the strength commonly used. 



Red spiders are best controlled by lime-sulphur dust, which is a powder 

 composed of equal parts of flowers of sulphur and dehydrated lime. 



Banding is occasionally useful, to prevent insects from crawling up 

 trees. Such insects as the bag-worm, the female of which cannot fly, 

 may thus be prevented from gaining access to trees already free from 

 their attacks. 



BANDINO MIXTURE 



Resin 16 pounds, castor oil 1 gallon. 



Heat until the resin is melted, then dip ropes in the mixture. The 

 ropes, covered with the banding compound, should then be tied around 

 the trees about four or five feet above the ground and renewed every ten 

 days or oftener if the mixture begins to dry and harden. 



FUNGI 



The next most important cause of injury to shade trees is fungus or 

 rot. Funprus diseases come under six heads: heart rot, sap rot, root 

 rot, canker, bark diseases, and leaf blight. 



Heart rot commonly occurs in old trees, which may be so badly 

 affected that the heart wood is entirely disintegrated, leaving the hol- 

 low tree to be supported by the outer shell of bark and sap wood. Since 

 the heart wood of the tree is dead wood its onlv function can be to 



