Phosphatic Manures and Turnips.

Te Aroha News, Volume IV, Issue 205, 28 May 1887, Page 3 (Supplement)

Phosphatic Manures and Turnips.

' With reference to the best phosphatic manure for turnips a Norfolk farmer gives some interesting results of experiments carried out by him which strikingly exemplify the importance of considering the nature of the soil to •which different chemical fertilizers are applied. The object of the experiments was to use ground coprolite against superphosphate in order to test the merits of soluble v. insoluble phosphates. The experiments with Swede turnips gave the following results :—: — No manure .. 15 tons 4 cwt roots 1 cwt. best Cambridge coprolitcs ground to impalpable powder .. .. It „ 5 „ „ 4 owt. superphosphate .. 13 „ 9 „ „ 4 cwt. superphosphate mixed with J cwt. bone flour 20 „ 1 „ „ Manures and yields of turnips given at per acre. With reference to the above results the cv penmen ter remarks :—: — " Now, it will not do, of course, to dogmatise from one series of experiment*, but if these are corroborated by those of another year, we may take it as pretty certain "Ist. That on this land, deficient in lime, a very acid supei phosphate used alone, is an unsuitable manure, or even an injurious one. '•2nd Thatground coprolite, whilst harmJess enough, no doubt, is also of very little, if any, service here as a manure. "3rd, That a very small quantity of boneflour (coprolite might have done as well) mixed witht he superphosphate some time before use makes a very efficient and economical manure, and one which is as harmless upon any soil as superphosphate alone would be upon soils containing much chalk or lime to neutralise the free acid. "Now, I have had very inferior results from bone flour alone, though certainly superior to coprolite, from which I have never had any benefit, and I therefore feel warranted by our experiments in suggesting that on limeless soils, a mixture of this bone flour with superphosphate should be tried against bone-llour and. coprolites, the former being so much the cheaper. Our oxperimenta upon chalky soil this year in Norfolk gave :—: —

JLUItn ■>. <3i manure.. i round. CoproHte Superphosphate IS, 12 14 17 1 9 Roots n ti