February, '13] BURGESS & ROGERS: GIPSY MOTH FOOD PLANTS 75 



President W. D. Hunter: The next paper, "The Results of Ex- 

 periments in Controlling the Gipsy Moth by Removing its Favorite 

 Food Plants," will be read by Mr. A. F. Burgess. 



RESULTS OF EXPERIMENTS IN CONTROLLING THE GIPSY 

 MOTH BY REMOVING ITS FAVORITE FOOD PLANTS 



By A. F. Burgess and D. M. Rogers, Boston, Mass. 



For many years great effort has been made to bring to perfection 

 the mechanical methods for controlling the gipsy moth. Aside from 

 the work of introducing the parasitic and predatory enemies of this 

 insect, experiments along the line of perfecting methods of control 

 have occupied a great share of the attention of the government and 

 state officials in charge of the moth work and of various investigators 

 and observers connected with it. In the earlier writings concerning 

 the feeding habits of gipsy moth caterpillars and in the experiments 

 which were conducted to test their ability to feed on the foliage of 

 the native tree growth of New England, the conclusion was reached 

 that this insect was a general feeder and that practically all the trees 

 or plants concerned would suffer severe injury on account of being 

 defoliated by the larvae. In fact, during the period when the territory 

 in the suburbs of Boston was the worst infested, about the years 

 1904 to 1906, large woodland areas were completely defoliated owing 

 to the enormous number and voracity of the caterpillars. 



Early in 1907 it was noticed that in many places, where the gipsy 

 moth defoliation had been severe, that the larvae seemed to show some 

 preference in the species of trees attacked. It was also observed that 

 white and pitch pine did not appear to be severely defoliated unless 

 they were growing in or near an area of hardwood trees. Realizing 

 the importance of this matter Mr. A. H. Kirkland, then superintendent 

 of the Moth Work for the state of Massachusetts, detailed Mr. F. H. 

 Mosher to carry on a series of laboratory experiments to test the feed- 

 ing of newly hatched gipsy moth caterpillars on pine foliage. These 

 were carried on during the spring of 1907 and were repeated the fol- 

 lowing spring. Mr. Mosher failed to rear first stage caterpillars on 

 this food. In the spring of 1908 an extensive field test was made, 

 using a clear stand of about live acres of white pine growth in ArKng- 

 ton, Mass. This experiment was carried on cooperatively between^ 

 the Massachusetts superintendent of Moth Work and Mr. D. M. 

 Rogers of the U. S. Bureau of Entomology. The locality was badly 

 infested and the trees on the border about 100 feet deep, were banded 

 with tanglefoot in order to prevent caterpillars from crawling into thq, 



