57 



and then forwarded to parties in the extreme northwestern part of 

 Xorth Dakota. Twenty-five poplar trees were killed in one locality 

 by these borers, and I have no doubt, although I can not obtain 

 absolutely accurate information, that some of the shipment was 

 distributed within our own State boundar3\ The nurseryman im- 

 porting this stock, of course, was in no way to blame in helping on 

 the westward progress of this unwelcome immigrant, since the cer- 

 tificate of the inspector was supposed to be an absolute guaranty 

 that the stock was all right. In complaining of this to the New York 

 commissioner of agriculture I was met with the statement that, while 

 it seems impossible to eradicate this beetle in New York State, 

 measures can and will be taken to prevent infested stock from being 

 sent to other States. Our nui-series in Minnesota have been carefully 

 inspected and found to be practically free from insect or fungous 

 pests. It should be said in this connection, however, that inspection 

 is not compulsory for all nurseries, and not more than two-thirds 

 desire it, namely, those who ship to other States, and others who do 

 not export, yet value the entomologist's certificate as an advertise- 

 ment of clean stock. Occasional occurrences of woolly aphis in 

 limited numbers are the only especially undesirable features dis- 

 covered in connection with nursery stock. 



Our shade trees, the soft maple and the elm, have been alarmingly 

 affected with the cottony maple scale {Pulvinaria innimierabilis 

 Kathv.) in many of our towns and cities, as well as in those of some 

 of the neighboring States. It has been present in such large numbers 

 as to check the growth of maple trees and weaken their vitality. 



Our attention has been called particularly to cecidomyiid gall- 

 makers on the box elder, the soft maple, and a locust, the variety of 

 which could not be given me. Specialists in this group at Washing- 

 ton, D. C, identified specimens mailed them as evidently C. negundis 

 Gill., C. aceris Shinier, and C. rohinia' Hald., respectively. From 

 (J. aceris we reared two parasites, Tctrastichus sp. and Mevapovus sp. ; 

 from C. rohmiw we reared a pteromaline, which Doctor Ashmead 

 pronounces an apparently undescribed genus. 



A species of Lecanium has occurred for several years on the coni- 

 fers in the experiment station forest, and this year has been particu- 

 larly troublesome on Scotch and jack pines. It evidently can 

 be controlled by spraying wdth kero-water or kerosene emulsion. 

 After one or two insecticide applications we found a coccinellid 

 {Hyperaspis sp.) in such large numbers, both larva^ and imagoes, 

 that we deemed it wise to leave the question of the " survival of the 

 fittest " to it and the scale upon which it fed. 



