POOD PLANTS OF THE GIPSY MOTH IN AMEEICA. 19 



Red Maple (Acer rubrum L.). 



When this maple is mixed with other trees more favored by gipsy-moth larvae 

 and the infestation is light, 'the feeding in all stages is light. When the 

 infestation is heavy and the other trees in the combination become defoliated, 

 or nearly so, the feeding becomes more intense, and in some cases defoliation 

 of this maple results. It is not, however, a favored food and will usually be 

 deserted for other species. 



In the laboratory, adults were obtained from trays started with first-stage 

 larvae on this foliage. 



Silver Maple (Acer saecharinum L.). 



In trays, first-stage larvae did not develop and produce adults, as all the 

 former died in the fourth or earlier stages. 



No field observations were made on this species. This is not as favored a 

 food as red maple. 



Striped Maple (Acer pennsylvanicunt L.). 



Larva? started on this foliage in any stage failed to reach the next stage. 

 It is one of the most unfavored of the maples. 

 No feeding of any amount was observed in the field. 



Sugar Maple (Acer saccharum Marsh.). 



Very few observations on this species have been made in the field, but the 

 observers are agreed that it is an unfavored food. 



In the trays at Worcester and Melrose Highlands the first-stage larva? grew 

 fairly well and a few male and female moths were obtained. It is less favored 

 than Norway maple and about as susceptible to attack as the red maple. 



Red Mulberry (Morus rubra L.). 



Mr. Collins tested this species in the laboratory at Worcester and found it 

 an unfavorable food for the gipsy-moth larvae. A few specimens passed into 

 the following stage, but none lived through two stages of it. No field observa- 

 tions have been made. 



White Mulberry (Morus alba L. ). 



White mulberry was tested in the trays at Melrose Highlands and about the 

 same results were obtained as with the red species, except that it is slightly 

 more favorable than the former. One male was reared from a tray started with 

 second-stage larvae. 



No field observations were made on this species. 



Black Oak (Quercus velutina Lam.). 



The oaks are among the most-favored food of the gipsy-moth larvae. The 

 young larvae begin feeding as soon as the buds are about half open. This is a 

 favored species and is eaten freely by all stages of the caterpillars and produces 

 large and vigorous adults. 



