FARMING NOTES

Bay of Plenty Beacon, Volume 2, Issue 199, 14 August 1940, Page 3

FARMING NOTES

THE ADVANTAGES OF THOROUGH CULTIVATION IN ROOT CROP PRODUCTION By C. R. Taylor, Department of Agriculture, Whakatane. Very much mere could be said of the great colonies of organisms that inhabit the soil, but time Avill not permit a longer discussion of them. Sufficient has been said, I' think, to bring home the truth that adequate cultivation is indeed of fundamental importance, for it is only by this means that congenial conditions of life for the essential organisms can be provided. Before passing on, however, allow me to once again restate these conditions. They are (1) the admittance of ample atmospheric oxygen into the soil; (2) reasonable soil moisture; (3) a comparatively high soil temperature; and (4) adequate supplies of humus. Farm is! thorough .methods of cultivation will, general]}' speaking, give you all four of these requirements without further trouble. In exceptional cases, of cou"-S2, extra drainage would be required additional to good cultivation, and on some of the light, humus lacking soils it m-glit also be an advantage to plough in green crops from time to time. Another Aspect. The next aspect of a soil that Ave shall have to consider before properly understanding the significance of thorough cultivation is the chemical aspect. This also is very important to the -well-being of plant life for the minerals that enter into the nutrition of plants arc combined in the hard, rcckv, particles that comprise the bulk of most soils. Noav you all know that the roots of plants cannot take up or absorb food in a solid condition. Plant food must be in a state of solution in a soil before it can be made .use of. Hence the necessity arises for some soil processes to bring the plant food contained in the rocky particles into a state of solution, or availability as it is often called. This task falls to the lot of the soil moisture which is charged Avith carbonic acid and probably other acids ..formed from the decomposition of vegetable matter in the surface layer. These mild acids then attack the gritty! particles of mineral matter and bring them gradually into a state of solution. Such plant foods as phosphoric acid, calcium, potassium and ( iron etc. are made available in this ( manner—plants then taking up as much as they require or is available to them. Altogether the chemical process is a very involved one, but it is clear that without a sufficient supply of soil moisture, plants Avould stance. Therefore, to keep this supply at an adequate IcA r el (not to the point of waterlogging, of course) but also for measures to prevent evaporation as far as possible. Only three things will ensure this objective and they are (1) good initial cultivation, (2) a suitable degree of soil consolidation, and (3) subsequent cultivation wherever practicable to control weed growth, and at the same time leave a loose surface mulch to retard evaporation. Building Cropping Capacity. Linking up the biological and chemical processes that take place in soil is one that is described as mechanical or physical. This pro-i cess has for its main purpose the breaking down of the rocky 'soil particles into smaller particles, and thus exposing a larger surface to the attack of soil moisture. In this way greater amounts of mineral plant food become available and as a result the fertility of a soil increases. With this increase in fertility plant life of the higher ord--crs is better supported.—more humus accumulates—bacteria and other micro-organisms arc stimulated to greater activity and finally the soil emerges substantially enriched in all the essentials for healthy crops. Since in the temperate zones the rain and the frosts are the chief agents associated with the Aveathering or breaking down processes of mineral matter, it is apparent that good cultivation can do much to hasten the work of these agencies by constantly exposing fresh rock oarticlcs to their dcA'aslating attention.

From what has been said, I think that everyone will now have a fairly clear conception of how thorough cultivation,, done at the right time, builds up the cropping capacity of a soil. On the other hand if cultivation is slip shod or otherwise incompletely carried out biological processes are slowed up, and the chemical and mechanical reactions are considerably reduced. Hence soil fertility is lower than it should be —the incidence of disease rises as the result of poor plant nutrition, and in the ultimate the farmer has to carry the burden of his neglect. Importance of Ploughing. So much then for the theory attaching to cultivation. Now for a few practical hints. Ploughing is probably the most important feature of the work connected with cultivation. If this is not done really well than it is a most difficult thing to make a good job of working down the land to a good seed bed. Generally speaking, ploughing for the root crop requires to be done as carl j- as possible to allow the weathering process that T have spoken of the utmost scope. An exception to this rule, however, is to be found in the lighter soils where the winter rainfall is heavy. Under these - conditions much valuable plant food is frequently wash-* ed out of tlis top soil to the detriment of the crop. Later ploughing would better suit such situations. If time permits it is an excellent plan to shallow plough first and follow Avith a deeper ploughing hirer. This practice facilitates the thorough rotting of the turf, and the subsequent incorporation of the decayed A'egetation in the top nbil. Moreover it proAddes better soil aeration and so measuroblv increases fertility. Achieving Consolidation. Following the plough the land should, if dry enough, be rolled Avith the furrow to settle down the furrow slices in close contact AA'ith the subsoil. -Th's is necessary to bring about the more efficient rotting, of the vegetation ploughed under and also to c'ose up the air space where the -furrows overlap. A double cut Avith the discs should then be given and the land left to SAveeten and Aveather until required for final preparation. A Aveek or lavo before the soAving date of the crop, the falloAved land should again be taken in hand and given a thorough working with the discs and harrows. When this is completed and a fine seed bed obtained—this is very important—a final rolling Avill generally suffice to achievc the requisite consolidation. Noav consolidation is important, not only on account of its part in the performance of the essential soil processes, but also as a meajns of preventing seed from being too deeply. Many farmers do nbt consolidate their land nearly enough before sowing their crops with the frequent result that strikes are patchy or even Avorse. This advice applies particularly to root cro,ps such as turnips, swedes and carrots — all of which have very small seed and Avill not produce a crop if buried too deeply. Preventing Evaporation. Where practicable inter-row cultivation should always be provided for, for not only does it facilitate weed control which is* necessary to godo yields, but It also ensures to the groAving crop the maximum amount of moisture by the prevention of excessive evaporation. In the North Island it is not customary to grow swedes and turnips in this way but mangels nrul carrots should always be groAvn AA'ith sufficient space betAvecn the ioavs to permit of working a horse-drawn cultivator. Yields are by no means sacrificed by the adoption of this method but are actually very much enhanced. .And this is what the country wants at the present time. My time is just about up so I Avill briefly restate the main points concerning the value of thorough cultivation in root crop production. They are:—• 1 . Remember that vour soil is not iust a dead mass, but very much ■live —or should be. A soil's fertility is substantially ■dependent upon bacterial and otner Continued at foot of next column)

minute organisms—the re lore take care of them. 3. Encourage the activity of the desirable micro-organisms of the soil by providing humus, warmth, moisture and oxygen. 4. Mineral plant food can only V*c made available to crops by the .solvent action of the soil moisture on the rocky particles. Therefore, conserve soil moisture by efficient .cultivation. . ' 5. The action of the soil moisture is most effective Avhen it can attack large surfaces if mineral particles Rain and frosit oombins to break up large particles into smaller ones and thus increase their surface. Farlj' ploughing and yood subsequent cultivation greatly assist in this work. 6. A fine and consolidated seed bed ensures a good strike and encourages capillary attraction. 7. Inter-row cultivation controls Aveed growth and prevents excessive evaporation. 8. conclusion only thorough cultivation -can open to you tire soil's vast storehouse and allow you your rightful share of nature's bounty. The key to this store-house is, therefore, in your own keeping.