SCIENCE WITH PRACTICE, AND THE CLOVER CROP.

Daily Southern Cross, Volume XXIII, Issue 3043, 27 April 1867, Page 6

SCIENCE WITH PRACTICE, AND THE CLOVER CROP.

To the Editor of the Wkkly Niws. __ Sib, — The following remarks on certain agricultural subjects from which benefit would be derived by the co-operation of scientific men with practical farmers, I think will not be without their utility, from the conviction that there are many matters which if the attention of scientific men were specially directed to, they would devote their knowledge and time to the elucidation and' discovery of the objects required of them. I believe few farmers will now call in question the propriety of enlisting the aid of science in many of the departments of agriculture ; indeed, I consider there is scarcely a science from which agriculture may not derive benefit : but it is only practical men who can apply, carry out, and make use of those discoveries with profit and advantage to the public and themselves. I will now direct your attention to a subject which, if it were thoroughly investigated, might lead to the discovery of the cause, and also of the cure, of the total failure of the clover plant on almost all Boils after a few repetitions of the four or five course rotation of cropping. There may be a, few soils which seem peculiarly adapted for its growth, and on which it flourishes still, though repeated every four or five years, but they are few and far between. We must take into consideration the cause of this failure, for generally spiking the readiest mode of curing any evil is first to endeavour to ascertain the cause of it. First— is it caused by any insect, the increase of which is promoted by the repetition of the crop too frequently, and which may be engendered or find an asylum in the decaying and deep-seated roots of the clover ? I think, -where insects have been found on the dying plants, it is far more probable that they have not been the cause of their dying, but are there in conaequsnpe of their being in a dying state. Secondly : Is the failure caused by the exudation of some feculent matter from the roots? — which has been averted by some aoieatific men to be the cavie,

and which being taken up by the roots of the young clover plants causes their disease and death ; which, cxuiation or poisonous matter requires several years before it is dissipated or becomes harmless. That this is the cause seems scarcely probable, because the same exudation must take place from the roots in those fields where it has grown or flourished longer without showing and symptoms of failure or udhealthiness in the plant, than it does in those fields which fail sooner growing it. Thirdly, and to my mind by far the most probable cause of the failure of the clover and other plants of the like kind when repeated often is, that there is some element or elements which enter into the composition of the clover and other plants of the leguminous tribe, which has hitherto ticaped the analyses of all our chemists, and which requires some years before it is replaced on the soil in sufficient quantity, either by the addition of manure, or from natural causes, if it be already in the soil, becomes in a fit or available state to be taken up by the roots, without which the plant cannot reach maturity or perfection. When it is cousidered that chemists have ascertained that the number of elementary or simple bodies in nature amounts to between 50 and 60, of which the analysis of plants has detected only about 14, in the composition of which the inorganic or earthy elements are about 10 in number, and that they severally vary in quantity in different species, and also in the different varieties of the same kind of plant, and that two or three of these elements cannot be detected at all in some plants, which are to be found in others of a different species, it is by no means unlikely that the failure of the clover is occasioned either by the abstracting from the soil of fone or more of those elements not hitherto recognised by chemists as entering into its composition ; or it may be caused by a deficiency of an element, already kuown to enter into its composition, not being in a tit state to be taken up by the roots, but oombiued perhaps with some other element, and which requires time for the slow solving process of natural causes, which are always in action, before it cau be produced in sufficient quantity for the next crop of clover to come to perfection. But, whatever the cause may be, I think it will be admitted that the assistance of scientific men in this matter is much wanted. It may be considered presumptuous for practical farmers to point out the way in which any experiments should be conducted ; but we may be allowed to offer any ideas that strike us, for their consideration, and make known any observations that we have made in connection with the object in view. Perhaps the most satisfactory and readiest way of solving the difficulty would be by following the method so successfully adopted by that most talented practical agricultural chemist Mr. Lawes, in those so admirably conceived experiments on the growth of turnips and wheat, carried on in the field, by which be demonstrates to conviction the condition of the soil and the several manures requisite to produce profitable crops of each, aud their mutual relation to each other in the course of rotation, which may be found in the journal of the R..E.A. Society, vol. xii , part 1st — a paper from the perusal of which no farmer, however experienced he may be, can rise without feeling that he has increased his knowledge of the economical application of the special manures most required by any crop he may wish to cultivate. But although few New Zealand farmers can effect an experiment on so large a scale as Mr. Lawes, still each, though ignorant of chemistry, may perform an experiment on the subject at a trifling expense of either time or trouble ; and Nature would furnish the answer whether our application of the remedy sought ( in the state or form we applied it) was luccesstul or not. The plan I would suggebt is this : In any field in which we purposely omitted sowing clover, on account of its being " clover-sick," we could sow a small patch of it with clover iv addition to the other grass-seeds sown over the rest of the field, and then if it failed there would be no loss or inconvenience arise. That portion sown with clover might be sown in two, three, or four parts, one of which should receive no application whatever ; the other portions theu might be dressed with any mineral or other manure which aright suggest itself to the mind of the person trying the experiment ; and here the scientific man might come to our assistance, and aid us by the information of what minerals, and in what form, it would most probably be useful to apply them. He would be guided in the information afforded by his knowledge of the composition of the soils on which clover flourished the longest without failure, and he could analyse the roots of those plants that were dying away in the spring, aud ascertain if there was any deficiency of the known elements, as compared with the roots of healthy and flourishing plants at the same period of the year. Apologising for so far trespassing upon your valuable space, — I am, &c, Matthew H. Fbost. Ararimu, April 24, 1867.