669 



IV. Species which are not favoured : Arbor vitae, arrow-wood, 

 maple-leaved arrow-wood, black ash, blue ash, red ash, white ash, 

 white and flame azalea, lir balsam, high blackberry, larger blue-flag, 

 butternut, hardy catalpa, red cedar, southern white cedar, cornus, 

 cranberry-tree, red currant, bald cypress, dangleberry, narrow dock, 

 flowering dogwood, American elder, swamj? eubotrys, f everbush, grape, 

 green brier, hackberry, pink hardback, white hardback, American white 

 holly, bush honeysuckle, highbush huckleberry, inkberry, poison ivy, 

 common juniper, Kentucky coffee-tree, mountain laurel, sheep laurel, 

 black locust, honey locust, mountain maple, striped maple, red 

 mulberry, white mulberry, Osage orange, red osier, pepperbush, 

 persimmon, privet, raspberry, sarsaparilla, skunk cabbage, spice-bush, 

 sweet brier, sweet pepper-bush, sycamore, Appalachian tea, tulip-tree, 

 sweet viburnum, black walnut, bay-leaved willow, smooth winterberry. 



The species noted in Class I. are at present dominant in the woodlands 

 in the area now infested with the gipsy moth. The oaks and birches 

 predominate over much of this area, and this increases the difficulty 

 of improving the situation. Most of the species of high commercial 

 value are included in Classes I. and II. In arranging combinations 

 which will resist moth attack it is necessary to consider the soU and 

 other conditions suitable for their successful growth and to endeavour 

 to bring about replacements cheaply. The encouragement of coniferous 

 growth is to be commended, provided the Class I. trees can be 

 eliminated. Experimental work with different stands of forest growth 

 is being conducted by Mr. G. E. Clement of the U.S. Bureau of Ento- 

 mology, and practical advice is being given. In addition to forest 

 trees and shrubs, plants of much importance to horticulture and for 

 ornamental and city planting are included in the above lists. The 

 apple is the horticultural crop most likely to be affected. The usual 

 controls are briefly mentioned. Cases of severe injury to cranberries 

 were observed in 1914 and the pecuniary loss is likely to be serious. 

 In cities and parks, or on street or shade trees, the control of the gipsy 

 moth requires large expenditure if the species favourable to the insect 

 are to remain. When future plantings are made, other species should 

 be selected and the lists given will furnish a guide in this respect. 

 An index of the food-plants used in the experiments, both the scientific 

 and popular names being given, is appended. 



BRU^rNER (J.). Douglas Fir Pitch Moth. — U.S. Dept. Aqric, 

 Washington, B.C., Bull. no. 255, 22nd July 1915, 23 pp., 10 figs. 



Investigation has made it evident that the larva of Aegeria {Sesia) 

 Tiowroewsis, Hy. Edw., (Douglas fir pitch moth) is the primary cause 

 of a large percentage of the depreciation in value of the timber of 

 Pseudotsuga taxifolia (Douglas fir). This amounts to at least 90 per 

 cent, in the northern Rocky Mountain and Pacific coast regions, and 

 the loss is similar in the southern Rocky Mountain district. In one 

 saw-mill, £3,800 represented one season's loss. In the spring of 1913, 

 an investigation was begun regarding the habits of insects aflecting 

 tha growth and development of trees, and information was gained 

 concerning the larval stages, etc., of this moth ; in the field, their 

 incubation period is about two weeks. With the exception of the 

 dark brown head, the larva is white ; the darker intestines and their 



