Investigations into the Intensive System of Grassland Management. By the Agricultural Research Staff of Imperial Chemical Industries, Limited. II. The Mineral Content of Intensively Treated Pasture and a Relationship Between the Nitrogen and Phosphorus Contents.

Abstract

1. The mineral content of pastures farmed under the Intensive System of Grassland Management, and representing three to five weeks'growth, from three centres in two seasons, is reported.2. The lime content fluctuated considerably during the season, but the fluctuations showed no definite seasonal trend. The average seasonal content was practically identical in all cases.3. The phosphoric acid content showed a definite seasonal variation, falling during drought or the early summer flush period and recovering again after the drought or flush period respectively. The phosphoric acid showed consistently a very highly significant positive correlation with the nitrogen content of the herbage. The bearing of this correlation on the metabolism of the plant and on the phosphatic and nitrogenous manuring of pastures is discussed.

The value of liquid digested sewage sludge. I. The effect of liquid sewage sludge on growth and composition of grass-clover swards in South-east England

“…Thus sludge and fertilizer treatments produced few significant effects on the mineral composition of the herbage. Those which have been observed are similar to those of Greenhill & Page (1931) who noted the correlation between nitrogen and phosphorus content, and to those of Rahman, Macdonald & Simpson (1960) and others, who observed the effects of fertilizer salts on the mineral composition of herbage. Thus liquid digested sludge produced herbage with a similar mineral percentage to that produced by equivalent artificial fertilizers, except that the percentage phosphorus was slightly lower, and this is correlated with the slightly lower percentage nitrogen present where sludge was used.…”

The chemical composition of native forage plants of southern Alberta and Saskatchewan in relation to grazing practices /

“…In pastures of more humid areas, where the grass usually is kept in the leaf stage, decreases of protein as well as of phosphorus often occur under dry condi- 21). The percentage of protein does not seem to be affected commonly in this way in the herbage of grazing lands in drier regions.…”

“…), total ash and crude fibre are determined. The crude protein content is calculated from the percentage of nitrogen by multiplying the latter by a standard factor (6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25).…”

A note on the employment of a mixture of sand and calcium bentonite as the growth medium in pot culture and the establishment therein of a sward of perennial rye grass

“…Bentonite(2) is a colloidal clay occurring in large expanses in deposits in various parts of Canada and America, from which it is dug and by pulverising, marketed as a pale cream-coloured powder 1 . Consisting mainly of a sodium clay (3), and exhibiting the usual characteristics of such clays, the bentonite was converted before use into a calcium clay.…”