LIME PLUS SUPERPHOSPHATE

Hokitika Guardian, 8 December 1930, Page 2

LIME PLUS SUPERPHOSPHATE

The effect of the combination of lime and super lias been an outsanding feature of the trials. Alinwst without exception the combination lias proved superior to either material alone. In about 10 per cent, of the trials no visible response 'from one or other of ;he individual treatments was discerlible, but when combined a distinct espouse lias been noted.

In only 2 oer cent, of cases is “no

isible response’’ recorded. In 76 per cent, of the trials the lime plus super plots are fair’y evenly distributed over the “Good,” “Very good,” and “Excellent’ response classes ,slightly more being recorded under “Excellent’ than in either of the other two classes mentioned. The importance of the lime plus super combination in connection with the establishment, and maintenance of pasture of short or long duration cannot be stressed too strongly. Experience indicates that rye-grass responds almost as well as clover, if not quite as well, to the addition of lime to soils deficient m it. The duration of effect df lime was discussed above, and the argument that liming is expensive cannot be admitted when it is remembered that the effect of a dressing of about a ton will continue for’live or six years. It is obvious that the best results cannot be got from super if lime is deficient.

POTASH, Tile results obtained indicate that in the main potash is not a serious limiting factor to pasture production in Canterbury ; 83 percent .of the experiments showed no visible response to potash in 7 per cent, the response was “doubtful,” in 4 per cent, “slight,” and in 2 per cent, “good.” Where responses did occur they were most marked as a rule where the potash plot crossed limed ground. The claim that potasn, though ineffective in improving yield, has a marked effect on the quality and feeding-value o'f grass herbage has not been substantiated so far as the writers are aware. NITROGEN. Responses to nitrogen were particularly consistent, over 80 per cent of the experiments falling in the “Fair” to “Good” classes so far as this factor was concerned. Generally speaking, the better the? rye-grass and cocksfoot content of the sward the better the response. to' nitrogen. The best results too, were obtained where the nitrogen plot crossed lime plus super although very often the super plus nitrogen plot were good.

In practically all experiments the best lot of the series was that receiving lime plus super plus nitrogen. It must be remembered, however, that 'from the commencement of the trials until May, 1930—just under two years—most of the experiments had received 5 ewt of nitrogenous fertiliser per acre, at a cost of about £3 5s per acre, In addition to the period of two to three months after application, when the nitrogen exercised a. direct influence, there has been a general improvement in the gras sward, The growth of clover has been reduced in a good many cases, but as a rule the reduction in clovers did not appear to be serious on the lime plus vsupet p|lus nitrogen plots. We do not. venture an opinion as to whether or not the use of nitrogen at its present price is paying. This must depend on a number of 'factors; hut one thing is certain—namely, that nitrogen will not pay on pastures which are lacking in the major specie*! of grasses—rye-grass and cocksfoot.

To those farmers who desire to try nitrogen, our advice is: (1) Use it on pasture which has been limed and phosphated; (2) use it only for the production of early spring grass by applying it in late July or early August, and possibly for production of early winter feed by applying in March or April; (3) use it on good pastures only, (4) feed off the resultant growth while it is still young and palatable. These remarks apply only to pastures used for grazing purposes.