258 POWER AND THE PLOW 



In the Columbia Basin of Washington, Oregon, and Idaho, 

 the annual rainfall is as low as eight or nine inches. Here the 

 usual practice is to summer fallow, and follow this with winter 

 wheat. After the fall harvest, if the ground is quite free from 

 weeds, it is possible to plow and leave it rough and cloddy 

 without further treatment until the following spring. It is 

 then in excellent shape to hold the soil and snow from blowing, 

 and to allow rain and melting snow to penetrate. Trash thus 

 has a better chance to decompose and the rains tend to settle 

 the ground. However, if the land is weedy, the better practice 

 is to use the tractor to disk and harrow the ground frequently 

 after harvest. Plowing is then done in the spring for the sum- 

 mer fallowing, or for the spring crop if one is sown. In some 

 sections of this Basin, near the mountains, the rainfall is suffi- 

 cient to allow two crops between summer fallows, a whiter 

 crop followed by a spring crop, or two spring crops in succession. 



There are sections in the State of Washington, where the soil 

 is a volcanic ash, or pumice, of such loose, gritty, character 

 that a traction engine, regardless of make or construction, is 

 speedily worn out. Into this district many have been intro- 

 duced, all meeting with the same difficulty. One would expect 

 land owners to become discouraged, but on closer investi- 

 gation, it is found that the violent storms of lava dust which 

 play havoc with even the heaviest parts of traction engines 

 make the use of horses during such times almost out of the 

 question. 



In the Dakotas and Montana new land is sometimes broken 

 to a depth of five or six inches to avoid the drying out of the 

 furrow slice which accompanies the method of shallow breaking 

 and backsetting. Authorities like Professor Shaw affirm that 

 the latter method makes it next to impossible ever to obtain a 

 seedbed deeper than the original year's plowing, while with deep 

 breaking and proper tillage there need never be a crop failure 

 in either state. With deep breaking i. e., at least six inches 

 a fair seedbed may be obtained at once, though at an enor- 



