108 MASSACHUSETTS HORTICULTURAL SOCIETY. 



sometimes in sucli numbers as to entirely destro}' the crop, but at 

 other times their depredations are scarcel}' perceptible and they 

 are either overlooked or allowed to share the crops, taking, in 

 most instances, a larger percentage than is usually supposed. 



It is this percentage that we should look after ; for, as the 

 margin of profits grows narrower by competition, it becomes a 

 matter of necessity to stop all the leaks, so far as possible, and the 

 destruction caused by insects is a very important loss. 



When one sees his crops so beset with insects innumerable as 

 to threaten their entire destruction, he leaves no stone unturned 

 in his search for knowledge about these enemies and the best 

 means for their destruction. For such cases we desire more 

 effectual means and more destructive agencies than are now 

 known, and to this end investigations will undoubtedly be made 

 in the various experiment stations about to be established in the 

 different States. 



I wish, today, to call 3'our attention more especially to the 

 losses caused by insects when they are not so very abundant and 

 are taking only a small percentage of our crops, because then we 

 are liable to overlook them or to regard them as of little impor- 

 tance, even when they are destroying all the margin of profit there 

 is on the crop. 



AVheu one finds a species of insect or several species attacking 

 any crop, there are two problems for him to solve as best he may : 

 first, what will be the amount of the destruction caused by these 

 insects if they are allowed to go on unchecked ; and secondly, 

 whether it will pay to take active measures against them. 



Not unfrequently persons make vague and useless attempts to 

 destroy insects, when the same expenditure, properly directed, 

 would have accomplished much good. I once heard of a man who 

 drove nails into the trunks of his apple trees for the purpose of 

 destroying the borers, a shingle nail for a small tree, a clapboard 

 nail for a medium-sized tree, and a board nail for a large tree ; 

 and of another man who went around periodicall}' and plugged up 

 the holes in the trunks of his trees from which the borers had 

 escaped, thinking they had just gone in and that he could kill them 

 by excluding the air from them. 



It is of importance, therefore, that the farmer or orchardist 

 should understand the life history of the insects he has to deal 

 with, from the egg up to the mature stage ; and, in manj' cases, 



