244 HEMIPTEEA. 



there in such incredible luxuriance, that many trees seemed, 

 at a short distance, as if they had been whitewashed. 



Mr. Knapp thinks that remedies can prove efficacious in 

 removing this evil only upon a small scale, and that when 

 the injury has existed for some time, and extended its influ- 

 ence over the parts of a large tree, it will take its course, 

 and the tree will die. He says that he has removed this 

 blight from young trees, and from recently attacked places 

 in those more advanced, by painting over every node or 

 infected part of the tree with a composition consisting of 

 three ounces of melted resin mixed with the same quantity 

 of fish-oil, which is to be put on while warm, with a painter's 

 brush. Sir Joseph Banks succeeded in extirpating the in- 

 sects from his own trees by removing all the old and rugged 

 bark, and scrubbing the trunk and branches with a hard 

 brush. The application of the spirits of tar, of spirits of 

 turpentine, of oil, urine, and of soft soap, has been recom- 

 mended. Mr. Buel found that oil sufficed to drive the 

 insects fi-om the trunks and branches, but that it could not 

 be applied to the roots, where numbers of the insects har- 

 bored. 



The following treatment I am inclined to think wUl prove 

 as successftil as any which has heretofore been recommended. 

 Scrape off all the rough bark of the infected trees, and 

 make them perfectly clean and smooth early in the spring ; 

 then rub the trunk and limbs with a stiff brush wet with a 

 solution of potash as hereafter recommended for the destruc- 

 tion of bark-lice ; after which remove the sods and earth 

 around the bottom of the trunk, and with the scraper, brush, 

 and alkaline liquor, cleanse that part as far as the roots can 

 conveniently be uncovered. The earth and sods should 

 immediately be carried away, fresh loam should be placed 

 around the roots, and all cracks and woimds should be filled 

 with grafting cement or clay mortar. Small limbs and 

 extremities of branches, if infected, and beyond reach of 

 the applications, should be cut off and burned. 



