Sulphate of Ammonia; Its Characteristics and Practical Value as a Manure (Paperback)

This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1900 Excerpt: ...of the nitrate of soda appears, on an average of eleven years, in the season after its application, and 26-8 per cent. of the effect of the ammonia salts. The amount of residue is much the greatest after a dry season, which has retarded the nitrification and distribution of the nitrogen of the ammonia. The facts now mentioned show a greater effect of residues from ammonia salts than of residues from nitrate of soda; a greater amount of residue in barley than in wheat culture; and a much greater residue at Woburn than at Rothamsted. Can we explain these facts? The far greater unused residue remaining in the soil after the growth of a crop with ammonia salts at Woburn than appears in the Rothamsted experiments is surely connected with the much later date at which the ammonia is applied at Woburn, and with the poverty of the Woburn soil in lime. Both of these facts must tend greatly to retard the completion of nitrification, and the subsequent distribution of the nitrates. As wheat and barley do not apparently assimilate nitrogenous food after flowering is completed, any nitrates formed after this stage of growth would remain unused in the soil, and if not subsequently lost, be available for the nourishment of the succeeding crop. It will be recollected that the ammonia salts are applied to the wheat at Rothamsted in March, but at Woburn at the end of April or beginning of May. The ammonia salts at Rothamsted are ploughed into the barley land at the end of February, or commencement of March; at Woburn they are usually top-dressed in the middle of May. There is thus apparently a good reason why a greater unused residue should occur in the Woburn experiments. We have to account, however, not only for the occurrence of a residue, but also for its preservation thr...