26 HINTS ON SOILS AND FERTILIZERS 
the needs of various types of soil, and is with¬ 
out doubt the most practical method of de¬ 
termining the needs of these soils. 
TILLAGE 
We will next take up the matter of tillage, 
There is no more important process in the man¬ 
agement of farm soils and crops than proper 
tillage. Proper tilth of a soil means the ease 
with which it can be worked. Of course, 
some soils are much easier to till than other 
soils; a sandy loam is much easier to farm than 
a hard, clayey soil. When we say a soil is in 
good tilth, we ordinarily imply that it has a 
crummy structure. A sandy soil does not neces¬ 
sarily need a large amount of organic matter 
to make it easily tilled, because the soil par¬ 
ticles are of sufficient size to maintain good 
tilth anyway. However, a large amount of this 
organic matter, incorporated in the soil is very 
desirable, even in sandy soils, because it serves 
to soak up the moisture for this type of soil, 
which is very important during dry weather. 
In fact, green vegetation, one form of organic 
matter, when turned under, is a big help for 
any kind of soil, as it usually assists in im¬ 
proving the physical character of the soil, and 
is a big factor in conserving the moisture. It 
may be likened to a sponge, in that it soaks 
up the surplus water, and holds it in the soil for 
a much longer period than would be the case, 
if this organic matter were not present. 
There are various reasons why soils are tilled 
on the farm. After a field is plowed, it is 
especially desirable to work up the soil into a 
