THE CHEMISTRY OF FARMING.

New Zealand Mail, Issue 1191, 28 December 1894, Page 4

THE CHEMISTRY OF FARMING.

For the successful cultivation of fruit trees we know that they require , potash, phosphoric r.cid, lime, nitrogen, and iron, and that these constituents must all be present in the soil at the same time. The plant requires to find them all at its disposal, and if one or more be absent the action of the others finds itself parjlysed. This is what is called the " law of the collective powers." In nearly all crops the plant requires to find more of one particular kind of plant food than of the remaining four, and this is part of the " law of dominants." Now the dominant of fruit trees is potash, and if we suppress the potash when applying manure to the orchard we find an enormous falling off in the fruit crop, but if we suppress any of the others the decrease is much smaller in proportion. Lime plays a most important part in the manuring of orchards, more especially when bonedusfc has been applied. The action of lime I explained in my letter on the cultivation of sugarcane, and I would recommend that one ton of quicklime per acre be applied once in three years, i or once in two years if the orchard is badly drained. Lime should not be ploughed in, but simply raked over the ground, as it will find its way down to the roots, ventilating the soil as it percolates through the earth, an} at ! the same time liberating from insoluble or dormant ingredients in the soil the alkalies (potash and soda), which are of I primary importance. Successful farming lies in obtaining ! the largest crops with the least expen- . diture of time and money, and we must , admit that it would be ridiculous as a

commercial investment to put on to any given crop in either manure or labour more money than it will return at the harvest to show a profit; In a recent Visit to some splendid orchards 1 was informed that the owners had been putting on tons of bonedust per year per acre, and the result was disease and general decay ] whereas had ' they applied half-a-ton per acre fairresults would have been obtained, although, as there is very little potash in bones, we cannot hope for good fruit crops by the use of this manure.alone. I give the analysis of bdhedusfc, so that we call seSe the ingredients that are to be supplied by some other manure : Moisture '... 9"90 Organic matter (4*57 ammonia) ... 33-70 Lime phosphate ... .... ... ... 49*12 Alklaline salts, magnesia, &c. ... ... $"18 Insoluble silioiotis matter ..-. .-.i l'lO 100-0 Iron in a soluble form is most necessary for healthy trees, and should be supplied in some mixed manure in winter or early spring. There is no doubt that our present system of working our orchards requires improvement, and it frequently happens that the most expensive manures aie used, perhaps because a friend recommends them or is the agent, and we like to give him a turn. To use these expen* sive manures without knowing, first of all, the ingredients of the soil on your farm is to be like the old woman who found a box of pills and insisted on taking them, as they might do good for some of her ailmentf. The soil is a grateful ar.d willing servant, but is governed by undeniable laws, the disregard of whioh can but result in failure. The farmer who bases his arrangements on a sound foundation will have a far better prospect of success than the farmer who endeavours to grow crops without considering the requirements of nature.—By Herbert Worsley in the Queenslander. , -,.. ~: .