ON THE LAND

Taranaki Daily News, 10 June 1930, Page 15

ON THE LAND

SUPER AND SOIL ACIDITY. SIR JOHN RUSSELL’S VIEWS. Sir John Russell, director of the famous Rothamsted Experimental Station, dealing with the subject of superphosphate as a manure, supports the arguments put forward by K.P. in an Auckland paper lately against tho idea that this fertiliser increases the acidity of the soil. He says in his report on agricultural research: —“There is an idea current among some farmers that superphosphate makes the soil acid. The modern scientific worker pays great attention to the observations of farmers, knowing from experience that they are often well founded, though the explanations given may be incorrect. But in this case the chemists have been unable to find any evidence of increased soil acidity. A considerable number of tests have been made by the Rothamsted staff in different parts of the country, but even the most delicate methods failed to reveal any increase in acidity that could possibly affect the crop. It is difficult to understand how the idea can have arisen as a farmer’s observation; it may have come from the American name for superphosphate—'acid phosphate’ —or from some assumed reaction in the soil. However the idea arose it appears to be inaccurate; but if any farmer thinks he has evidence that his soil has been made acid by superphosphate the writer would be glad to have information about it. Statements have been made that superphosphate increases the liability to finger and toe (Plasmodiophora brassicae) in swedes, turnips, etc., and this has been quoted as evidence of increased acidity. If this statement were correct (and there is difficulty in getting proof) it would not prove increased acidity. The nodule organism is known to move about more easily in the soil when some soluble phosphate is present; it is then more liable to infect plants than where there is no soluble phosphate.”

CASEOUS LYMPHADENITIS. NEW SOUTH WALES CAMPAIGN. The .Scientific Research Committee of the Graziers’ Association of New South Wales presented a report to a recent meeting of the general council on caseous lymphadenitis in sheep and lambs, which embodied a recommendation that a campaign of cleanliness should be undertaken.

Attention was directed to the necessity for the highest degree of cleanliness in shearing sheds and all places where sheep are handled, and to the proper use of disinfectants, also that combs, cutters and shears should be frequently cleaned and disinfected; that to prevent infection to lambs grassseed paddocks should be eaten out so that lambs may be placed there during the grass season, also that at shearing and crutching time sheep showing discharging abscesses should be culled out of the flock.

The committee recommended that special endeavours should bo made to insist upon better shearing so as to avoid cuts, which are considered to be the means of spreading caseous lymphadenitis. It further suggested that local committees be recommended to arrange for the district veterinary officer to address local meetings and to afford all available information as to desirable steps for prevention o-f caseous lymphadenitis and other - diseases, and that such meetings be held preferably before shearing time. Acting under the authority given by the General Council, November, 1928, the association has provided a refrigerating equipment in connection with the research which is being undertaken at the Sydney University by Mi*. Carne in connection with caseous lymphadenitis, the cost being £350. The equipment will subsequently be installed in the McMaster laboratory. An amount of £75 has also been, made available to Mr.. Carne for the purpose of experimental sheep and stock food.

vidcd for rotational grazing. Consisting of 50 acres, the area is sub-divided into 16 paddocks, all of which are in grass. The adoption of an improved method of pasture management and the further subdivision of the farm into sm«ll fields had -led to a considerable increase in the carrying capacity of the holding. The system. of rotational grazing followed on Mr. Ward’s farm consisted of treating tho grasses as a crop and allowing the pasture to reach a length of from 3in to sin. The pasture was grazed and then spelled until the next crop of grass was ready for feeding off. The farm was sub-divided in a way that provides a central raes upon which all the paddocks open. Referring to the experiments carried out on Mr. Ward’s farm, Mr. J. W. Woodcock, agricultural instructor at Hamilton, said that it was unwise to enter upon an extensive scheme of rotational grazing until experience had been gained in the proper management of grassland under an intensive system of grass farming in which regulated harrowing and mowing of rank growth and systematic top-dressing had all played their parts Figures quoted in connection with the exhibit show that during the 1929-30 season Mr. Ward grazed 36 cows on the 50 acres. They yielded ll,llolbs of but-ter-fat, or ah average of 2221 b butterfat per acre and 3'oBlb butter-fat per cow. Manure consisting of superphosphate and sulphate of ammonia at the rate of 6cwt per annum had been applied. The farm was top-dressed' with 2cwt of fertiliser in Mai'ch, July and December, and in addition lOcwt of lime per acre was distributed. Potash had also been used.

There was considerable diversity in the response of the pasture to the application of sulphate of ammonia, said Mr. Woodcock, those paddocks in which ryegrass predominated giving the best yield in feed. From 22 to 25 cows could bo comfortably grazed in fields of" two acres, while for herds of from 35 to 38 cows threeacre paddocks had proved satisfactory. -Adequate control of tho pasture and the provision of a good supply of water were among tho factors that required consideration.-. In commencing a system of rotational grazing, it was stated that tho scheme should bo developed gradually, and that four or five fields were sufficient to start with. The pastures in these fields should be treated as liberally as possible. Farmers were advised to make provision for a reserve of hay and ensilage before commencing more intensive methods of grazing. It would be necessary for the pastures to bo supplemented by grass ensilage, hay or concentrates should a shortage of green feed occur.