522 BoAnn of AOKTci't/rfirK. 



OKCIIAKI) K.XEMIES AND MOW TO COMBAT THEM. 



I'rof. Troop: Mr. Cliairuitin. Eadies and Gentlemen— There are two 

 classes of enemies to the orchards— insects and fungous diseases, and there 

 .iro so many varioties of those chisses that if I were to spealc of all I am 

 afraid we sliould not get to bed toiiiglit. Not very soon, at least. But I 

 will only sijcal; of a few of the priiuipal ones, and a few of the essentials 

 in combating llicni. of llie insects, one tiling 1 want to spoalc of princi- 

 pally is the fact that we must keep in mind, in figliting insect enemies, 

 that there ai-e two classes. Those belonging to o«e class might be called 

 eaters, or chewers, wliile tliose belonging to the other class might be called 

 suckers. The one class eat their food— chew tlieir food— while those be- 

 longing to the other class suck their food. Now, it makes a very great 

 difference when you come to applying insecticide.s— it makes a very great 

 difference whether tlie insect belongs to the one or the other of these 

 classes; and that is the first thing to consider when an insect attacks our 

 trees or plants, the orchard we are speaking of particularly. The first 

 thing is to notice how it takes its food. If it is eating the foliage or fruit, 

 or any part of the tree or plant, we apply some one of the arsenates, that 

 will poison it when it is taken into its system. On the other hand, if it is 

 a sucking insect, getting its food by sucking and causing the leaves to roll 

 ni) and witiier without being eaten, we must apply an entirely different 

 remedy— one which will kill liy coming in contac-t with the insect. So the 

 first thing to have in mind is that there are two classes of insects, one an 

 eater and the other a sucker. 



Of those affecting the apple Ave have the codling moth, the fine web- 

 worm and the cankerworm, these feeding on the foliage and the codling 

 moth on the fruit, and the flat-headed borer on the trunk. The apple is 

 infested by the curculio, also, to a considerable extent. Of course, the 

 codling moth does not eat the foliage, but it eats the fruit, and the young 

 finds its way into the apple, and the remedy is Paris green or some of the 

 arsenates that Avill kill by taking them into the stomach. Paris green has 

 been used mostly for that, and also disperine, arsenate of lead, that comes 

 in the form of a paste, and gives great satisfaction. We found this year 

 that one spraying at the right time with the disperine has been sufficient, 

 and trees that were sprayed last May, still have the disperine showing on 

 them. It is more adlicsive and sticks to the tree better than the Paris 

 green, and that is its principal advantage. 



As for Paris green, I might say that in using that I would always use 

 it with lime. We generally use the Bordeaux mixture and the Paris green 

 -together for the codling moth and the apple scab of which we have been 

 speaking here today, which takes both the apple and the foliage. This 

 does not seem to have any on it, but you have all seen it. You all know 

 what the apple scab is. It attacks the fruit, making scabby places, and 



