166 The Rocky Mountain Locust. 



and perpendicular, they may be protected by whitewash- 

 ing. 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 

 whitewashing 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 employed for preventing the ascen- 

 sion of the female Canker "Worm, puts an effectual estop- 

 pel on the operations of the young locusts above the point 

 of attachment, for they can not jump from and alight again 

 on the same perpendicular surface. A strip of tin three or 

 • four inches wide, brought around and tacked to a smooth 

 tree, will protect 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 the rope, or the rope and 

 tree, can then be blocked by filling the upper area be- 

 tween 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 

 coal tar or some poisonous substance, to prevent girdling. 

 This is more especially necessary with small trees. 



One of the cheapest and simplest modes is to encircle 

 the tree with cotton batting, in which the insects will en- 

 tangle their feet, and thus be more or less obstructed. 

 Strips of paper covered with tar, stiff paper tied on so as to 

 slope roof-fashion, strips of glazed wall-paper, and thick 

 coatings of soft soap, have been used with varying success, 

 but no estoppel equals the bright tin. The others require 

 constant watching and renewal, and in all cases coming 



