-239- 
Nebraska 
California 
Nebraska 
FALL WEBWOEM: ( Hyphantria cunea Drury) 
M. H. Swenk (June 15- July 15): The fall webworm began to 
appear on the trees in such numbers as to occasion complaints 
during the last few days in J u ne and the early part of .July, 
PACIFIC RED SPIDER ( Tetranychus pacificus MeC-regor) 
E. A. McGregor (July 23): Probably the worst pest of shade 
trees in the great SanJoaqiin Valley of California is the 
Pacific red spider. There are :facts which indicate that the 
sycamore tree, Blatanr s racemosa ,, may be the native host of 
this mite. Very severe injury occurs every year to a certain 
percentage of these trees, resulting at times in almost com- 
plete defoliation. The chinaberry or umbrella tree, is the 
commonest ornamental tree in the cities and towns of central 
California. Frequently the streets are lined solidly with 
these trees. Almost every summer the Pacific red spider be- 
comes so abundant on the chinaberry trees as to cause very 
heavy shedding of foliage, resulting commonly in the loss of 
their shade value. .Certain 'citiSe (LindEsy ;'.£ or 6xesp4$) 
maintain a department of pest control for the almost exclusive 
purpose of combating this pest. During the present season 
every tree in town has been sprayed at least once, and many of 
them twice. The present correspondent has for the past several 
years conducted an incidental study of this pest and hopes to 
publish on it eventually. 
GALL MITES ( Eriophyes spp.) 
M. H, Swenk (June 15-July 15): Gall mites of various 
species continued to be reported during the second hrlf of June 
and early July. These included not only the pouch galls on 
wild plum and elm mentioned in my last report, but also during 
the latter part of June the walnut velvety leaf stem gall, 
Eriophyes sp., and the linden leaf gall, E. abnormis . 
ASH 
South Dakota 
Nebraska 
ASH TREE BORER ( Podosesia fraxini Lugger) 
H. C. Severin (July 12): Shade trees and windbreaks* are 
badly injured in numerous sections of the St'tte. This is the 
most serious pest of ash. 
ASH APHID ( Pemphigus fraxinifolii Thorn.) 
nM. H. Swenk (June 15-July 15): The ash aphid was reported 
injuring ash trees during the period covered by this report. 
