CEREAL CULTIVATION GREAT PLAINS 355 



Farm show that best results are obtained with two plow- 

 ings, the first one being in May or June, with as much 

 surface cultivation as possible between the plowings. 



382. Wind erosion and soil-blowing. - The loss of soil 

 by water erosion in the Eastern area has been discussed 

 (330). In the southwestern and central western parts 

 of the Great Plains, where there is much sandy soil and 

 strong winds are frequent, soil removal occurs under 

 opposite conditions of dryness and a light soil, instead of 

 great rainfall and an impervious soil. The agent is the 

 wind, and the effects are probably equally destructive. 

 The wind, usually from the southwest, first picks up par- 

 ticles of sand from a specially loose portion of the field 

 and, with these as tools, erodes the surface ahead, increas- 

 ing its effect rapidly from rod to rod until great clouds of 

 dust and sand are formed. Soil-blowing, long continued, 

 will actually excavate the soil sometimes as deep as it is 

 plowed. The effect upon young plants is to cut them off 

 as though with a knife, and then bury the portion remain- 

 ing. One field or portion of a field will affect another, 

 so much so that often the latter would probably lie un- 

 disturbed if isolated. 



383. Prevention of soil-blowing. -- First, much soil- 

 blowing would be avoided if, at the time of original 

 breaking of the sod, the latter were not carried so far into 

 the sandier part of the farm. This sandier part, when 

 broken, will blow, and will then affect adjacent portions 

 which might not otherwise be disturbed, Soil-blowing 

 may be partially or wholly prevented in the following 

 ways: (1) Immediately when blowing begins, prompt 

 use of a disk or smoothing harrow to roughen the sur- 

 face will at least check the effect greatly ; (2) increasing 

 the soil humus by application of barnyard manure is a 



