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The practice of alternate cropping and summer fallowing is a 

 common one in the semiarid region. Where this is done the land is 

 kept thoroughly tilled during the year of summer fallow so as to 

 store up the moisture of two years for the use of one crop. The 

 value of this practice of allowing the soil to remain bare during the 

 entire season is questionable, for, though it may serve to give good 

 results for a few years, it must necessarily result in an almost com- 

 plete destruction of the organic matter in the soil. This will bring 

 about such a physical condition of the soil that it will no longer re- 

 tain moisture as it did when it contained an abundant supply of or- 

 ganic matter. 



A much better practice is to raise some kind of a leguminous 

 crop which can be turned under before it becomes hard and woody 

 and while there is still a sufficient amount of moisture in the plants 

 and in the soil to cause rapid decomposition. The physical as well 

 as the chemical composition of the soil will be improved by this 

 practice instead of injured, as is the case where bare summer tillage 

 is practiced. 



Winter Tillage. Not only is it important to keep a well-estab- 

 lished dust mulch on all cultivable land throughout the summer, but 

 effective measures should be taken to catch and hold all the mois- 

 ture possible that may fall during the winter. In cold climates, 

 where the soil remains frozen, but little tillage can be given. The 

 south, however, is comparatively warm in winter, so that much soil 

 moisture may be lost by evaporation unless the ground is narrowed 

 or cultivated so as to establish a dust mulch after rains. 



The usual method is to stir the surface of the ground as soon 

 as it can be worked after each rain. Winter harrowing of fallow land 

 may seem to be an expensive operation, but in the South it is very 

 likely to make the difference between success and failure, and 

 the expense is really not very great where proper tools are used. 



Deep or Shallow Plowing. The depth of plowing must be de- 

 termined by the farmer himself. He knows the conditions and is 

 the best judge of the cost. In many sections, if done in the fall, it 

 undoubtedly pays to subsoil 15 or 20 inches. The advice to go down 

 gradually is given solely because the inexperienced farmer may try to 

 plow too deeply the first time and bring to the surface too much of 

 the subsoil. The best plan is to use the disc plow, so set that it will 

 not bring the subsoil to the surface. Generally it may be sent down 

 8, 10, or 12 inches with impunity, and, if done in the fall, with slight 

 addition to the cost of shallower breaking. Double plowing that 

 is, to break at the usual depth and then follow in the same furrow 

 with a narrower plow or scooter and go down as deep as desired is 

 better than shallow plowing, though a little more expensive plan than 

 the use of a disc plow and not so effective. There is no question 

 that breaking and pulverizing to a depth of 8 to 10 or 12 inches and 

 adding plenty of humus is economical. Whether a plant has plenty 

 of food all the time or only part of the time makes the difference 

 between a good crop and a poor crop. Concretely stated, a deep, 



