28 BULLETIN 995, U. S. DEPAETMEXT OF AGBICUX.TUKE. 
and crop production when we consider the number of acres under 
cultivation and the satisfactory crops that the tillable area is capable 
of producing when properly fertilized and tilled. Furthermore, a 
considerable portion of the stable manure produced on most sugar- 
beet farms is wasted or rendered only partially effective either by 
not giving it proper care or by the method in which it is handled in 
connection with crop production. In addition to the humus con- 
tained in stable manure, considerable quantities of plant food are 
present, which, if properly handled, add to the fertility of the soil. 
This plant food is largely soluble : consequently the leaching process 
to which the stable manure is in most cases subjected, owing to the 
fact that it is usually exposed to rains and snows, frequently causes 
much of the fertility to be lost. Again, stable manure is often spread 
upon the fields and left exposed to the weather, until a large part of 
the volatile plant foods has passed off into the atmosphere. Much 
of the nitrogen is often lost in this manner. The best results in 
utilizing stable manure in connection with sugar-beet production are 
obtained by applying the manure to the crop preceding the beet 
crop : this allows the manure to be thoroughly worked into the soil. 
It is a common practice in many localities where manure spreaders 
are not used to haul the manure from the feed yard or stable at 
times when there is no urgent work to be done and to dump it in 
piles, to be spread at some convenient time before the ground is 
plowed. This is a wasteful method, especially if the piles are left 
for some days or weeks without spreading, often resulting in much 
loss of valuable material through leaching. However, this method 
is preferable to spreading the manure and leaving it on the surface 
of the ground exposed to the action of the sun and wind. If the 
manure is spread and the ground can not be plowed immediately, 
it should be disked whenever practicable: that is, if the ground is 
not frozen. Fortunately, the manure spreader is becoming more 
and more common, and where the number of live stock on the farm 
warrants it there is probably no other implement of greater value to 
the farmer. The full value of the spreader is not realized, however. 
unless the manure is plowed under or worked into the soil imme- 
diately after spreading. 
Green crops. — Green crops plowed under provide another source of 
humus for soil improvement. Any vegetable matter plowed under 
and worked into the soil will add humus, though certain crops are 
more valuable for this purpose than others, because of the plant food 
a- well as the vegetable matter which they contain. Such crops as 
peas, beans, clover, and alfalfa, are among the best for supplying 
humus to the soil. These crops should be plowed under in the fall 
so that they will have abundant opportunity to decay before the 
<>Towin2" season begins the following year, In irrigated sections 
