Controlling Factors

Categories: THE USE OF STABLE MANURE

The farm supply of stable manure is a carrier of

plant-food, returning to the soil four fifths of all the fertility

removed in the crops fed, but it is much more than this. Land which

receives only plant-food, as may be the case when fertility is supplied

in commercial fertilizers, loses good physical condition. Organic

matter is needed for maintenance of physical condition, the retention

of soil moisture, the freeing f inert minerals in the land, and the

promotion of bacterial life in the soil. No small share of the value of

a ton of manure is due to its organic matter. This is a factor in the

problem when deciding what disposition of the manure will pay best. One

field may be in condition to respond fully to the use of commercial

fertilizers, while another is too deficient in humus for best results.

Some crops are more insistent upon supplies of organic matter than

others.



Again, the disposition of the manure depends upon the supply. If most

crops are fed on the farm, the manure is a leading source of fertility

for all fields and crops, and may be used once or twice in the

crop-rotation on every field. If the manure is in small amount, due to

a scheme of farming involving the growing of crops for market, the

function of the manure may be only to encourage the starting of sods,

in which legumes are a leading factor.