FARMING NOTES.

Pukekohe & Waiuku Times, Volume 4, Issue 14, 19 February 1915, Page 4

FARMING NOTES.

Soil Inoculation. A few years ago there was a boom in soil cultures and soil inoculation. Scientific professors possessed of more enthusiasm than knowledge of practical agriculture started a crusade in which a new era was promised to agriculture. By tbe uee of soil cultures crops were to be grown on land hitherto cousidered half barren, and tbe application of extensive fertilisers was t) ba rendered unnecessary. Experience has shown tnat these expectations were a great illusion, and in consequence the theory of sj:l cultures ft. 11 into disrepute to an extent which p.rhaps is not justified. At least that ia the idea that one gathers fr.m a perusal of "A Review of Work on Soil Inoculation," by Messrs J. Golding and H. B. Hutchinson, who may be accepted as ajthortiies on the subject. In this revi»« it is poiuteJ out tfat since tne int:oluction of pure cultures of nodule bacteria for soil injculation by Nobbe and Hiltner in 1895, a vast ruraber of field experiments has bJeti carried out in different countries anl with a great vaiety ot inoculating material. ihe resuKs of euch experimental work were m the first instance most disc uragiag and it is only within the last few years that the corditicns determining success or failure have been adeq lately recognised. During this time the relations existing between tte host flh't and the nodule organism and letween the organism and artificial media used for cultivation in the laboratory have been studied in detail, and in th; light of these investigations it is not surprising that failure attended much of the preliminary and often haphazard fi.ld work. Exptrience has shown that it is not sufficient to fave a pure end active culture in o dtr to attain tuccess in soil inoculation, hut that tbe si il it°elf shall be suitable forth; gro th and continued existence of the introduced organism, and that the supply of mineral nutrients shall nut be the limiting factor in tie growth of the plant. Liming has been requried in many cases, and with a proper recognition of tbe now known essential condit ons, the number of successful cases of inoculation trials has tteadily increased during recent years.

Comparative woik with pure cultures and inoculati n by mtans of soil which has previously carried a specified leguminous crop have shown in the majority of cases the euperiority of the latter, and cultivation in tbe laboratory has latterly included the use nf eoil media or soil itself, since the organism appears to retain its power of infection to a greater extent in this than in other media.

'lhe use of pure culture po'sesses advantages on the score of cheapness and convenience, which are sometimes of distinct value, and recent woik especially has shown the danger attending transference of plant diseases in soil used for legume inoculaiton. The relations attending infection of the plant and subsequent mutual existence Bre very complex, and future experimental work in preparing cultures must aim at reproducing these conditions in order to permit of the production of cultures in active growth and possessing great virulence.

Such work, however, involves accurate scientific control if it is to b3 of permanent benefit to science ard agriculture, and in itself would tend to check the production of commercial cultures of doubtful origin and hypothetical value.

The Soil. SUPERPHOSPHATE v SLA'j. The latest bulletin of the Aberdeen and Nnrtb of Scotland College of Agriculture reports the result of some experiments carried on in connection with the college by Mr Bruce, of Inschfield, to test the relative effect, as manures, to superphosphates and basic elag on the feedirg value of turnips. In many, if not must, of the experiments which have hitherto been made with these manures, the results have bten measured merely by the increase in the weight of the crop, though there have been experiments in the feeding cf sheep. But in the Aberdeen experiments cattle have been employed, and another point of differentiation from previous tests is that equal coney valuep, not equal weights, of the two manures were applied to the experimental plots. There is a widespread opinion that slag-raanur.d turnips are r.ot of such good feeding as those manured with other fertilisers. It has been stated that they cause souring and that animals fed on ttnm do net thrive well, The Aberdeen experiments do not ccnfirm that view. In no casi during the two years did any of the cattle fed with slag-nwnured turnips scour or exhibit any digestive or other trouble which could be ascribed to the food, and tbe increases in weight of the two lots were practically equal. la the first year the animals fed with the slag turnips made an average increase of 81b more than those fed with the superphosphate turnips, while in the second year those fed with the superphosphate turnips made the g.eater average increase by 1110. With the exception of certain accidental hurts which were met with by Eome of the slag-turnip-fed cattle, and which set them back somewhat, all tbe animals in both sets feJ well and throve. There were no notable differences in the quality of the turnips as shown by analysis, and although in regard to the weight of the crop, the yield of the slag-manured area was in the second year much greater than that from tbe superphosphate area, that is not relied upon as modifying or contradicting the general result of many experiments, which is that, for equal quantities of phosphate, superphosphate produces on the average a somewhat heavier crop than basic slag, but that for equal values of phosphate they produce approximately equal crops. The general conclusion drawn from the experiments in the report ia that turnips grown with ba9ic blag are of quite as good feeding quality aB those manured with Buperphoshate.—"Agricultural Gazette."