BUREAU OF ENTOMOLOGY. 227 



work was carried on against the Black Hills beetle from 8 to 10 

 years ago under the supervision of representatives of the bureau were 

 found to be practically free from infestation by this beetle, which, 

 previous to the control work, had caused the death of a great quan- 

 tity of the best yellow-pine timber. The inspection showed that there 

 had been a long- continued influence of the control work, not only 

 within the treated areas, but over a wide adjacent and intervening 

 territory. 



In November, 1915, an inspection was made of the White Top 

 Purchase Area in Virginia and Tennessee to determine the results of 

 the control work against the southern pine beetle which had been 

 carried on by the Forest Service under the recommendation of the 

 bureau. It was found that the treatment of 1,612 of a total of 2,612 

 infested trees, or about 61 per cent, served to reduce the infestation 

 on the treated and adjacent areas 96 per cent below the amount of 

 infestation found at the time the control work was started. When it 

 is considered that there had been ample time for the development of 

 at least three generations of the beetle, this is a most convincing 

 demonstration of the economy and efficiency of the methods recom- 

 mended, and especially of the percentage principle of controlling this 

 most destructive insect enemy of the pine timber of the Southern 

 States. 



Insects affecting shade trees and hardy shrubs. — A prelimi- 

 nary survey of Long Island, New York, and of the street and park 

 shade trees of the cities along the coast in Connecticut, Rhode Island, 

 and Massachusetts, was made during the season of 1915 to determine 

 the principal insect depredations on the trees and hardy shrubs and 

 the special needs as to investigations and advice. The results showed 

 that the most important insect problems were represented by the 

 dying hickories and oaks on Long Island. Further investigations 

 revealed the fact that the death of the hickories was due to the 

 hickory barkbeetle and that the death of the oaks was due to de- 

 foliation by the cankerworm and forest tent caterpillar and subse- 

 quent attack by the two-lined chestnut borer. It was found that 

 tens of thousands of hickories and oaks had been killed by these in- 

 sects during the past year and that very little had been done to 

 prevent it. 



Special attention has been given to determining the distribution 

 of the trouble on Long Island and locating communities in which 

 demonstration control work might be conducted and information 

 and advice given which would enable property owners to save their 

 trees. It was found that the trouble affecting both the hickories and 

 oaks was almost entirely confined to the western end and northern 

 half of the island and principally along the north shore. Demon- 

 stration control work was conducted under the supervision of the 

 bureau on Lloyd Neck, where 942 hickories and 911 infested oaks 

 were cut and burned by the property owners, and near Jericho, 

 where 151 hickories and 1,067 oaks were disposed of. In addition, 

 between 8,000 and 10,000 trees have been treated in accordance with 

 the advice given, namely, to locate and mark the trees that die during 

 the summer and fall and cat and utilize them for fuel or other 

 commercial purposes, or pile and burn them during the winter and 

 early spring. An extensive campaign is being carried on this sum- 



