failure of growers to get satisfactory results in the employment of the 
recommended measures, that directions had not been properly fol- 
lowed. Operations against certain pests, to be successful, must be 
done with exactness. The requirements are sometimes too compli- 
cated, involving considerable familiarity with entomology, so that the 
average man is unable to properly carry out directions. For such 
cases demonstration work has a legitimate field. It is perhaps an 
open question whether the responsibilities of the economic entomolo- 
gist go any further than to study the life and habits of a given pest 
and to point out the appropriate remedy, leaving the matter of its 
utilization entirely with those directly concerned; but it has been 
much to the good of the cause that many workers have demonstrated, 
sometimes over and over again, the benefits to be derived from insecti- 
cidal applications. Indeed, this has been no small part of the work 
thus far. 
Future problems will probably not materially differ in character 
from those of the past, but more and more should methods of preven- 
tion replace the actual apphcation of insecticides. If there is any- 
thing in the idea that varieties differ with respect to their suscepti- 
bility to insect attack, this matter should be thoroughly investigated. 
Certain facts might be adduced that seem to indicate that this is, in a 
limited way, true. Certain of our native vines are more resistant to 
Phylloxera than European varieties descended from Vinifera. The 
Northern Spy apple is said to be much less subject to attack from the 
woolly aphis than other varieties, and its roots are often used as graft- 
ing stock on this account. The immunity of the Kieffer pear from 
the attack of the San Jose scale is a matter familiar to most of you. 
The different varieties of plums vary much with respect to their sus- 
ceptibility to the curcuho. Other similar instances might be given. 
The possibility of protecting trees and plants from insect attack Ly 
the use of certain fertilizers or the introduction into the circulation, 
through the roots or otherwise, of substances objectionable to insects, 
has often been suggested. Recent investigations abroad indicate suc- 
cess In this method of preventing insect injury. Doctor Smith, in this 
country, has been able to reduce the injuries of the pear midge by the 
use of kainit. and this same fertilizer is considered valuable in protect- 
ing cabbage, onions, and numerous other plants from certain of their 
insect enemies. Thorough detailed life-history studies must replace 
the often scant remarks concerning the four principal stages of 
insects, and this improvement is already well under way. The inter- 
relations between insects and their environment, e. g., their parasites, 
and the influence of climate, altitude, and soil, is as yet almost an 
untrodden field. A more accurate knowledge of the laws governing 
the distribution and successful existence of insects must furnish mech 
ef practical value. 
