ORGANIC MATTER.

King Country Chronicle, Volume VII, Issue 573, 4 June 1913, Page 2

ORGANIC MATTER.

There is sometimes a misuse of the termß "organic matter" and "humm" There are two classes of organic matter —the active and the inactive. Inactive organic matter consists of crop residues that remain after several years, and which decompose very slowly—this is humus. If it is present in a large quantity its gradual decomposition will supply sufficient nitrogen to meet the needs of most crops. Active organic matter consists ot such substances as decaying plant roots and crop residues, green manures and animal maures. These products decay rapidly in the soil, and in the process of decomposition liberate not only plant food which they contain, including nitrogen, phosphorous, and potassium, but they also set free other decomposition products as nitrrc acid, carbonic acid and organic acids, which have power to dissolve more or less additional plant food from the mineral part of the soil. It is because of this that a soil may be rich in humus yet less productive than another, while the two soils are alike in other respects. An abundance of humus makes a soil friable and permits the tender plant rootlets to seek moisture film and plant food, but active organic matter is necessary to provide plant food in solution for profitable crop yields on most lands.