GRAIN CROPS 



49 



with one or two bundles so placed as to shed water and 

 protect the heads of grain from sun and dew. If well set, 

 a shock of this kind will not easily be blown over. The butt 

 end of the cap sheaf should not extend beyond the shock. 

 Stacking. — Stacking is quite an art, and men pride them- 

 selves in building uniform, straight stacks that will not 

 blow over and that will protect the heads from the sun and 

 rain. The foundation of a stack generally consists of a 

 sufficient number of upright sheaves leaning against one 

 another towards the center. On these other bundles are 

 laid horizontally in tiers, with butts out and overlapping, 



Figure 18b. — Kernels of wheat, enlarged 



beginning at the outside. Each layer, for several feet, 

 should extend a few inches beyond the one below it, to form 

 a ''bulge." The reverse process should then be followed 

 to the top. For several feet also the top of the stack should 

 be kept level. Then the center should be built higher so 

 as to afford a slope to the edges. Rain will thus run out- 

 ward and off. 



Threshing. — Wheat is often threshed from the shock. 

 This method is cheaper. There is always risk of damage 

 when grain is kept exposed, but convenience and other cir- 

 cumstances often make it advisable or necessary to stack. 



