﻿130 EIGHTH ANNUAL REPORT 



corners for that purpose. The entire expense of the "trap" is about 

 $3.50, and as it is light and easily handled will be found serviceable on 

 small as well as large farms." 



Zinc instead of oil cloth has also been used for the same purpose. 



The experience of last Spring shows that when the insects are 

 famishing, it Is useless to try and protect plants by any application 

 whatever. Sweetened water seemed to keep the winged insects oflf 

 special plants in 1874; but it certainly has no such effect on the un- 

 fledged hoppers, for they " went for " plants which I thus sprinkled 

 even more voraciously than for those not sprinkled. Lime does not 

 deter them; neither coal oil nor cresylic soap will keep them from 

 eating ; and Paris green, though it undoubtedly kills those which par- 

 take, is yet no protection to plants, because those which go off to die 

 somewhere after partaking are continuously followed by others which 

 go through the same experience. I gave carbonic acid gas, from a 

 Babcock fire extinguisher, a thorough trial under many different cir- 

 cumstances and conditions, but without any satisfactory results. It 

 had very little effect upon them even when played upon them con- 

 tinuously and at short distance. They often became numbed by the 

 force of the liquid but invariably rallied again. 



The best means of protecting fruit and shade trees deserves sep- 

 arate consideration. Where the trunk is smooth and perpendicular, 

 they may be protected by whitewashing. The lime crumbles under 

 the feet of the insects as they attempt to climb, and prevents their 

 getting up. By their persistent efforts, however, they gradually tear 

 off the lime and reach a higher point each day, so that the whitewash- 

 ing must be often repeated. Trees with short, rough trunks, or which 

 lean, are not very well protected in this way. A strip of smooth, 

 bright tin answers even better for the same purpose. Encircling the 

 tree in any of the different ways suggested for preventing the ascen- 

 sion of the female Canker Worm, puts an effectual estoppel on the 

 operations of the young locusts above the point of attachment, for 

 they cannot jump on a perpendicular surface. A strip of tin three or 

 four inches wide brought around and tacked to a smooth tree will pro- 

 tect it ; while on rougher trees a piece of old rope may first be tacked 

 around the tree and the tin tacked to it so as to leave a portion both 

 above and below. Passages between the tin and rope or the rope and 

 tree can then be blocked by filling the upper area between tin and 

 tree with earth. The tin must be high enough from the ground to 

 prevent the hoppers from jumping from the latter beyond it; and the 

 trunk below the tin, where the insects collect, should be covered with 

 some greasy or poisonous substance to prevent girdling. This is more 



