Elements of agricultural chemistry, in a course of lectures for the Board of Agriculture / By Sir Humphry Davy.

  • Davy, Humphry, Sir, 1778-1829.
Date:
1813
Catalogue details

Licence: Public Domain Mark

Credit: Elements of agricultural chemistry, in a course of lectures for the Board of Agriculture / By Sir Humphry Davy. Source: Wellcome Collection.

    393/428 (page 37)
    oz. 784080 0 or lbs. =49005 per acre 0 0 }196020 0 =12251 0 0 drying - 3675 4 0 f 30628 2 = 1914 4 2 XLVIII. Trifolium pratense. W. Bot. 3, P. 137. Broad-leaved cultivated clover. Nat. of Britain. At the time the seed is ripe, the produce from a rich clayey loam, is Grass 72 oz. The produce per acre 80 dr. of grass weigh when dry 20 dr. The produce of the space, ditto 288 dr. The weight lost by the produce of one acre in drying 64dr. of grass afford of nutritive matter 2.2 The produce of the space, ditto 45 dr. If the weight which is lost by the produce of this species of clover, in dry- ing, be compared with that of many of the natural grasses, its inferior value for the purpose of hay, compared to its value for green food, or pasture, will appear ; for it is certain that the difficulty of making good hay increases in proportion with the quantity of superfluous moisture which the grass may contain. Its value for green food, or pasture, may further be seen by com- paring its nutritive powers, with those manifested by other plants generally esteemed best for this purpose. Tr folium pratense (as above) affords of nutrititive matter - 2.2 dr. XLIX. Tr folium repens (white clover) from an equal quantity of grass 2.0 dr. L. Ditto, variety, with brown leaves, ditto 2.2 dr. The grass of the T. pratense, therefore, exceeds in value that of the T. repens, by a proportion, as 8 to 10 ; but if is of equal proportional value with the brown variety. LI. Burnet (Poterium sanguisorba) affords of nutritive matter - 2.2 dr. LII. Bunias orientalis, (a newly introduced plant), ditto - - 2.2 dr. The proportional value of these two last, and of the T. pratense, and the brown-leaved variety of T. repens, are equal: they exceed the T. repens, as 8 to 10. The comparative produce of these four last mentioned species, per acre, has not been ascertained. *