LEGUMES AS MANURE

Sun (Auckland), Volume II, Issue 400, 14 July 1928, Page 25

LEGUMES AS MANURE

BENEFICIAL EFFECTS A CANADIAN EXPERIMENT In a publication, issued recently by the Department of Agriculture for Canada, dealing with manures and fertilisers, there is a short account of an investigation conducted by the Division of Chemistry in respect to the enrichment of the soil by the growth of clover. The soil from a plot was removed, to a depth of eight inches and replaced by soil of a perfectly uniform character containing 0.0437 per cent, nitrogen. At the commencement of the investigation lime, phosphoric aclg, and potash were applied. Mammoth red clover was sown and the plot was kept in clover for ten years. It was cut down when deemed necessary throughout the season, the plants not being permitted to seed, and the material was alloweid to decay on the soil. Every second year the plot w * dug over and resown. The soil was sampled and analysed from time to time, and the following are the results : NITROGEN Percentage Pounds in per acre water- to a free soil depth of 4in. Before experiment .. 0.0437 533 After two years .. .. U. 0550 798 After four years .. .. 0.060 S 742 After five years .. .. 0.0659 S4l After six years 0.0744 90S After seven years .. .. 0.0750 915 After nine years .. .. 0.0524 1,005 After ten years 0.0556 1,044 Increase in nitrogen due to ten years' growth 0.0419 511 Thus, over a period of ten years, tlie clover had enriched the soil to a depth of four Inches with nitrogen to the approximate amount of 500 pounds an acre or 50 pounds a year. “This ni trogen,” states the report, “although not; present iD an immediately-avail-able conditions. Is associated with res.dliy decomposable organic matter, and would be set free for the use of succeeding crops.”