AGRICULTURAL AFFAIRS.

Evening Post, Volume LXXXIII, Issue 154, 29 June 1912, Page 14

AGRICULTURAL AFFAIRS.

SUPERPHOSPHATES AND SOIL MOISTURE. The Pastoralists' Review publishes the following interesting information on tlio matlejc of superphosphates and soil moisture supplied by Mr. H. Pyo, principal ot tho Dookio Agricultural College, Victoria, and Mr. G. M. M'Koown, principal of tho^V>gga Experimental Farm, Now South Wales: — Mr. Pye says:— "Superphosphate in, itß relation to the soil ig occupying the attention of a number cf scientists interested in agricultural problems. Undoubtedly tho rate at which capillarity is able to move water through tho soil is influenced by tho nature of the salts held in Bolulion. As a. general rule, tho effect of limo salts on a clay soil is to reduce it= capillarity. This is duo to their binding effect on tho particles that give clay its plastic nature. This plasticity 1 is also ascribed to tho prosefice of 'colloid hydrates, which in tjio presence of moisture form a jelly-liko medium. As is generally known, tho application of lime to clay soils -renders them moro friable, and tho capillary action more rapid. "Judging trom my experience* here, tlio marked difference in capillarity of tho virgin Dalkeith soil, and tho Bame soil treated with so small a dressing of superphosphates as 451bs<to tho aoro (a quuntity that would scarcely btJ appreciable if mixed through five or six inches of tho ourf ace soil), leads me to think that the experimental conditions undor which tho capillarity tests were carried out were not similar. "The reason why so small a dre/ssing as 451 be to the aoro so frequently "givps good results when drilled m'-nith the seed, is probably the stimulus given 10 tbo plants during their early growth, thoir root systems being well developed, duo to the presence -ot tho^ supply of available- plant food just after the toed < erminates. If, on the othor haud, the 4Blto, of superphosphates per acre wore broadcasted and the seed drilled in after, almost tho yields aro not ounfaibly improved, much heavier dressings of the fertiliser being necessary to obtain a result similar to tho above. "It may be said that tho soluble phos phates in. tho fertiliser 'soon revert to thu! more or less insoluble phosphates of -alumina and iron. "However fertile a soil may be, its, physical condition is tho most important consideration, if the best results aro toi bo obtained, either with or without the application of fertilisers. Good tillage brings about those important changes in' the physical character and condition of a soil that renders it much more fertile than, a similar soil -that has suffered neglect in this respect,. "Much (scientific research in relation to the action of superphosphates and other fertilisers vvhon applied to tho soil is bemg carried out. We know that the results of tho application of fertilisers to the soil vary with tho nature qf the seasons, and these variations, irrespective of the' physical conditions, , affect the clihiato within the soil, and so the generous work of those beneficial unseen friends of the farmer— tho bacteria within the soil. When the ideal physical condition of the VBoil has been attained, then, by the ap-' plication of fertilisers tho direct and the indirect benefits derived by their presence modifies the part played by tho moieturo present,' less moisture in this, instance being needed in order to elaborate each pound of plant issue. There is a limit, i may say, to tho soluble salt content of t. soil which plants can. make use of. "In general, the main factor in regard to the comparative yields of crops on two adjacent fields is their physical condition, and 'thu« it happens that tho soil that is better tilled gives improved yiolds over a similar soil not co well treated. 'Ab phosphoric acid is generally deficient in our soils its application in a great measure leads to good results, but how much to a direct, and how much to an indirect influence is a problem yet to be solved. 1 ' Mr. M'Keown say£: — "I do not, think that tho direct action of superphosphates inoroaßOß capillary action in the soil. "Tho superphosphatp used is generally in such small proportion to the soil contained N in 3iu to 6iu depth of soil aB to . bo in bulk unappreciable. In comparing < the area as superficial the fertiliser occ'u-' pies only ono-seventh part, the depth of the deposit boing so slight as to make it', almost imperceptible. "If the mechanical effect; of suporphos-' phates is, as suggested, to increase capillary action, then such action should bo increased proportionately by the application of larger quantities of tho fertiliser. My own experience has shown tho con-u-ary ,as a moderate quantity, Bay, 661bs, h»6 given bettor results than four times the quantity. • "I bavo applied to wheat, fertilisers of which 93 por cent, was superphosphate, the relative cost of which was 12s to 17s 6d per acre, and the resulting crop waß loss than that obtained from a supply which cost 2s 6d (tho former was evenly distributed and promptly covered). In one instance there was a slight increase in yield, but in all cases the grain harvested, from the area which received tho heavier dressing had a much larger proportion of pinchod grain than whore the 561bs super, was appliod, the grain show ing all the sigiu. usually present when insufficient moisture has boen available. "Some years ago a crop was sown here with 2001bs super, por aoro, and the following year over a considerable portion of tho area the fertiliser was discovered to be intact, which I think is a further proof that it did not affect capillary action, to any appreciable extent, aB in. that oasu traces of the fertiliser could not have been found. ' Tho crop was one of the worst I have had. * "The increased vigour and productive ness of crops treated with superphosphate under our conditions aro so completely beyond doubl< that, except for demonstration .purposes, I should never think of ! sowing a crop without the manure. "I believe that the reason for the large-ly-increased crops obtained from email quantities of superphosphates sown with tho seed is that jts direct effect is to increase the root system of plants, enabling them tb extend, their rumincations in search of bustenanco deeper and wkW than is possible with unmanurod crops. Apart/ from this plant food is added by tho application of superphosphate. "Last season at tho farm measurements wero taken of tho roots of wheat both manured and unmanured when the plants wore about four months old. Those treated with manure had roots 6m deeper, and tho'nunibor and extent of all roots Wiis largely in excoes of those of untreated plants'. Tho maximum depth of roots was S4in. Tho crops compared wore Biu high. Communication would tliUB be established with the moisture iv the subsoil, and this, with tho shado affordod by tho improved crops, would greatly influence the soil moisture in tho uppei? strata. 'I estimate that tho effect of ,a moderate application of'superphesphate drilled vMtli tho seed in oquivr.ibnt to a 4in to siu rainfall for tho reason's above slated."

Mr. Brtun Stoker, who was for nearly thirty years the intimate friend of Sir Henry Irving, the great actor, died at St. Georgc's-square, London, on 20th April. Brain (or Abraham) Stoker, was born in Dublin in 1847, and was educated at Trinity College, where' he won honours in science, mathematics, oratory, history, and composition, besides distinguishing himself as a sportsman and debater. Ho entered the Irish Civil Service, then beeam'o editor of an evening paper, and dramatic critic; but about the year 1876 he came in contact with Henry Irving, and two years later had thrown in his lot with the actor, becoming his manager and confidential secretary. From 1878, the year in .which Irving became lessee and manager of the Lyceum Theatre, to 1905, when he died, tho takings, according to Stoker, exceeded £2,000,000. When the crash came, Stoker remained loyally at his friend's side, and afte^ bis death undertook to write his biography and performed it in the midst of much arduous work with customary enthusiasm.