154 The Rocky Mountain Locust. 



the same land the following spring ; for, thus brought to 

 the surface, the eggs more often hatch. 



The experience as to deep plowing under of the eggs is 

 somewhat conflicting, and in some light, dry soils, a good 

 number of them will hatch late if turned under a foot ; yet,, 

 from my own observations, and a vast amount of experi- 

 ence gathered together, I recommend it as profitable. If 

 delayed till spring, it should be done just as the young 

 begin to hatch, as it is then most effectual. The plowing 

 will be effectual according as the soil is porous or tenacious, 

 and according as the surface is afterward compressed by 

 harrowing and rolling. From the experiments already 

 recorded, it is obvious that, all other things being equal, 

 a plowing of four to six inches will prove more effectual 

 in spring, if the ground be subsequently harrowed and 

 rolled, than deeper plowing with no subsequent comminu- 

 tion and compression. 



IRRIGATION TRAMPING. 



Where the ground is light and porous, excessive and 

 continued moisture will cause most of the eggs to perish ; 

 and irrigation, or alternate submersion and drying of such 

 land, will likewise prove beneficial. It is less useful, how- 

 ever, than is generally supposed, and on tenacious soils 

 will have little effect. 



Wherever hogs or cattle can be turned into the fields 

 where the eggs abound, most of these will be destroyed 

 by the rooting and tramping. All these means are obvi- 

 ously insufficient, however, for the reason that the eggs 

 are too often placed where none of them can be employed. 



In such cases, they should be collected and destroyed by 

 the inhabitants, and the bounty laws, presently to be con- 

 sidered, are useful in this connection. 



