Show PHOSPHATE ROCK IS USED AS FERTILIZER If Finely Ground and Well Distributed Distributed Distributed Gives Good Results This Source of Phosphorus Being More Extensively Used Than Formerly Formerly For For- merly on Account o of Shortage of Sulphuric Acid I Prepared by the United States Department Department Department Depart Depart- ment of ot Agriculture Acid phosphate which Is used extensively extensively extensively ex ex- ex- ex as a commercial fertilizer has doubled In price during the last few years Farmers of this country are arc now facing a serious shortage of ot this material because the munitions Industry industry In in- Is consuming much sulphuric acid which would ordinarily rily be bc used In Inthe inthe I the Uw manufacture of ot acid phosphate The situation has hns led users of ot fertilizers fertilizers fertil fertil- to give ghe greater grenter consideration to the use of ot ground raw rock phosphate That this source of ot phosphorus Is beIn being belag be be- In lag ing used as fiS fertilizer more extensively ly IK lq shown h by the lire fact tact that during Juring IOta 1910 17 at nt least six large companies entered the tho raw ground phosphate business and the annual consumption of this material has hns Increased during the lust decade to over tons Involving an on expenditure to the farmer of at least Ground raw row rock phosphate Is furless fur far farless furless less soluble titan than acid phosphate Its effectiveness appears to be due largely to Its thorough distribution In the soil sull This Is brought about by liberal applications of very cry finely nel ground rock together to gether with good tillage When all these conditions are arc not fulfilled It may mn take several years Jars to obtain the distribution giving the maximum ef ef- ef feet The beneficial effects of a comparatively com corn heavy heny application of finely ground rock phosphate extend over several years cars as 08 a n portion of Qt the time phosphate phosphate phate becomes soluble each ench year To be most effective ground phosphate phosphate phate rock should be applied to soil that Is well supplied with organic mat ter tel Such soils are always ha s 's richer In carbonic acid than those of ot low organic or 01 organic ganic c content and this acid Is Important important tant in effecting the solubility and availability I of ot tho the phosphate rock I |