HEMIPTERA. 



213 



tree will die. rfc 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 insects 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 recommended. Mr. Buel found that oil sufficed to 

 drive the insects from the trunks and branches, but that it 

 could not be applied to the roots, where he stated numbers of 

 the insects harbored. The following treatment I am inclined 

 to think will prove as successful 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 destruction 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 wounds should be filled 

 with grafting cement or clay mortar. Small limbs and ex- 

 tremities of branches, if infected, and beyond reach of the 

 applications, should be cut off and burned. 



There are several other species of Eriosoma or downy Hce 

 in this State, inhabiting various forest and ornamental trees, 

 some of which may also have been introduced from abroad. 

 The descriptions of foreign plant-lice are mostly so brief and 

 imperfect, that it is impossible to ascertain from them which 

 of our species are identical with those of Europe; I shall 

 therefore omit any further account of these insects, and close 

 this part of the subject with a few remarks on the remedies to 

 be employed for their destruction generally, and some notice 

 of the natural enemies of plant-lice. 



