GREEN MANURING.

Colonist, Volume LIV, Issue 13413, 10 May 1912, Page 8

GREEN MANURING.

Tho uso of green manuro is to improve the mechanical condition and absorptive properties of the soil. This object is aix ained c/iiefly by virtue of the vegetable organic matter contained in these man ures as, of course, they do not add to the mineral constituents of the soil. From the standpoint of added plant food, peas, in common with other leg umes-, arc valuable in being .able-to secure the element of nitrogen from the atmosphere, while from the lower layers of the soil and subsoil mineral constituents are rendered available for the succeeding crop. In actual test experiment it has been found that a crop of pe-2s ploughed down as green manure, and estimated to woigh about five tons per aero, furnished 23501b of organic vegetable matter, or as much as would be furnished by 7% tons of average stable manure. The fertiliing constituents in a crop of this weight would amount to 15.51b of nitrogen, 12.6 of phosphoric acid, 52.8 of potash and 9.8 of lime — considerable less phosphoric acid, but almost as much nitrogen and potash as would be furnished by the manure mentioned. With the . exception of the nitrogen these constituents had prevariously existed in the soil, and were brought to the surface in an available plant food form, hence one of the main advantages attended upon the practice, of green manuring with leguminous r;rops. Tho nitrogen, on the other hand, being equivalent in amount to 3841b of nitrate of soda, is a direct gain to ;he soil, inasmuch as it is drawn from the atmosphere.