TILLAGE. 



89 



by the spade it does not stick to the tool, then plowing throws apart the granular masses 

 along the lines of the dry -cracks, and the soil is adequately loosened. 



Some clay-lands are very difficult to till at all in spring time. In drying, they form not 

 many small, but a few wide cracks, and when they are dry enough below to crumble as the 

 plow passes, the surface is already baked to clods, so that after plowing, the clod-crusher a 

 series of toothed wheels revolving independently, but close together, on a common axle is 

 needed to actually pick and cut to .pieces these tough lumps. 



Other clay lands thaf are very close-textured and heavy when wet, slack or fall to pieces 

 as they dry, and on such soils early spring tillage may be practiced, and in short seasons may 

 be necessary to dry out the land. This class of clays, and many heavy loams remain for a 

 long period wet at the surface during the spring rains, as they retain water with great tenac 

 ity, and although they dry out finally, and come into good condition after a time, yet time 

 may be made and seed 

 got in earlier by put 

 ting the plow to work 

 and actually raising 

 the earth and shaking 

 it in the air (as we 

 would lift and agitate 

 a wet cloth), for the 

 sake of drying out the 

 excess of moisture, 

 which, if not removed, 

 would cause planted 

 seed to rot. This dry 

 ing of the soil is an 

 essential preliminary 

 to warming it up to a 

 point favorable for the 

 germination of seeds 

 and growth of young 

 plants. 



The best time to 

 plow heavy clay lands 

 for loosening their 

 texture is the autumn, 

 soon after the crops 

 have been removed, 

 and before the naked 



surface hardens under the late rains. Fall plowing may be done, if needful, when the clay 

 is wet, for if plowed dry it will become wet, and wetting is an essential part of the loosening 

 process. Alternate freezings and thawings of wet clay will loosen it as no other agency can. 

 Water in freezing expands ^th its bulk, and the energy of its expansion is enormous. This 

 energy is exerted throughout the entire mass of the frozen earth, and in its finest pores. 

 But severe frost is needful, for, under sufficient pressure, or in strong capillary tubes, as in 

 the fine pores of brick and sandstone, water either does not freeze because it cannot expand, 

 or it requires a temperature much reduced below 32 Fahrenheit for its congelation. 



The act of freezing not only effects a mechanical separation of adjacent particles of sand 

 and silt between which the water expands into ice, but it has a special influence on the real 

 clay; When water, turbid from suspended clay that would remain without settling for weeks 



TILLAGE IN INDIA. 



