46 INJURIOUS INSECTS OF KANSAS. 



The protection of fruit- or shade-trees against the young Differ- 

 ential and Two-striped locusts can usually be effectively done. 

 Doctor Riley's recommendations are as follows : 



Where the trunks are smooth and perpendicular they may be pro- 

 tected by whitewashing. The lime crumbles under the feet of the in- 

 sects as they attempt to climb, and prevents their getting up. By 

 their persistent efforts, however, they gradually wear 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 well 

 protected in this way. A strip of smooth, bright tin answers even bet- 

 ter for the same purpose. A strip 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. Pass- 

 ages between the tin and rope or the rope and tree can then be 

 blocked by filling the upper area between the 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 coal-tar or poi- 

 sonous substance to prevent girdling. This is more especially neces- 

 sary with small trees, and coal-tar will answer as such preventive. 



One of the cheapest and simplest modes is to encircle the tree with 

 cotton batting, in which the insects will entangle 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 tight tin. The others require constant 

 watching and removal, and in all cases coming under our observation 

 some insects would get into the trees, so as to require the daily shaking 

 of these morning and evening. This will sometimes have to be done 

 when the bulk of the insects have become fledged, even when tin is 

 used, for a certain proportion of the insects will then fly into the trees. 

 They do most damage during the night, and care should be had that 

 the trees be unloaded of their voracious freight just before dark. 



Mr. George Gibbs, of Holden, Missouri, found that the whitewash 

 was rendered still more effectual by adding one-half pint of turpentine 

 to the pailful. 



4. The complete destruction of the winged insects, when they 

 swoop down upon a country in prodigious swarms, is impossible. 

 Man is powerless before the mighty host. Special plants or small 

 tracts of vegetation may be saved by perseveringly driving the 

 insects off, or keeping them off by means of smudges, as the 

 locusts avoid smoke. 



Certain of the means used in fighting young locusts (unfledged 



