142 NATURE STUDY AND AGRICULTURE 
Preparation of Seed Bed. — Generally it is best to plow 
the ground in the fall, so that it may absorb and retain as 
much moisture as possible. Fall plowing is also an advantage 
because it gets that much out of the way of the spring work. 
It is especially desirable in the case of wheat. For corn, 
Types oF NORTHERN GRAINS 
potatoes, and barley, spring plowing is quite common, though 
where the rainfall is deficient fall plowing may be better for 
these also. Ground on which corn has just been raised does 
not require plowing. Before seeding, fall plowing and un- 
plowed corn and potato ground must be thoroughly disked 
to loosen it up, and spring plowing must be well harrowed. 
After seeding, the harrow may be used again as the earth 
should be made as fine as possible. 
Selecting and Testing Seed. — The importance of planting 
good seed is well recognized by all practical farmers and 
gardeners. The kernels should be large and plump, and 
care should be taken that they have not lost their vitality 
