ON THE LAND.

New Zealand Herald, Volume LI, Issue 15520, 30 January 1914, Page 10

ON THE LAND.

PRUNING THE APPLE.

_ . , i . The vigorous winter pruning found necessary in forming a stout-limbed apple tree causes a great many strong shoots to start which are not required as leaders. To remove these entirely when fully 'grown appeals to one as being wasteful. To cut them back a little in winter only aggravates the evil by causing an increased number to appear during,the following summer. There are three methods of dealing with these growths (laterals), ■ which cannot possibly be retained as leaders, and which, at the same time, are likely to extend to such a length as to cause overcrowding. The first consists of pinching out the growing tip after it has developed half-a-dozen good leaves. This is done in the spring or early summer, and must, in most instances, be repeated again upon the subsequent which invariably arise from the shoot when it recovers from the temporary stopping. This is a timeconsuming work, but excellent results in the direction of forming short spurs have been obtained by its application to varieties which produce long, thin laterals, such as Jonathan and Rome Beauty. The second method is to wait until the lateral has reached almost full length (say, at midsummer), then cut it' off from 4in to 6in above its base. The guiding factor in this operation is the moistures in the soil, because, if sufficient still remains, or a fresh supply is given immediately after by rain showers or irrigation, the pruned shoot will break into renewed growth. This may not prove the work to be altogethertougatory, because while one or two buds may extend into uselessly long growths, one or more of the others near to the base of _ the stump often progress into that short-wood spur stage which is the object sought by the operator. The third method consists of partially breaking the lateral through at about the same distance from its base as described above. The portion beyond the fracture is allowed to hang down, with its leaves attached, for the remainder of the summer, but is pruned away in the following winter. To cause the development of the short-leaf spurs from buds upon the basal segment this operation must be dona when the sap has almost, but not quite, ceased to flow. The chief disadvantage attached to this method is the overshadowing of the lower portions of the tree by the dense foliage of the hanging, partially-damaged laterals. At the best the starting of the buds upon the basal portion of the lateral into a very restricted form of activity, so as to cause them to develop sooner into fruit spurs, which shall be close up to the stiff parent limb, is all that can he hoped for from these two operations as far as the laterals under treatment are conoerned. There are so' many influences operating against the accomplishment of this object that, with the exception of those laterals for which there is no room—those arising between the framework, limbs, or intruding into the centre too far, or growing from the high, slender portions of the leaders — changing of the nature of the shoots by such artifices presents a problem of considerable uncertainty. One thing, however, is sure : the removal of trashy, crowding twigs admits abundant sunlight and air to the spurs, which form naturally from buds whose; vigour has been, restrained by the growth of new shoots more advantageously situated. The light and air keeps these natural spurs sufficiently healthy to enable them to develop their terminal "buds up to the flower-forming stage at an earlier portion than ,if they had to wait for the crowded laterals to open' out by means of their own weighty and extended development. When the summer's growth has just about reached ' completion, the best wood shoot, or at most two, upon each leader of last year, should be selected to continue the framework, and any others, if; not previously manipulated as described, may be absolutely suppressed:

(THE CULTIVATION OF OATS. Oats are cultivated ,011 a wider acreage than either wheat or barley. - \ It is very v important that the seed should be entrusted to the soil at an early date. If the grower should have been fortunate in this respect 'and has selected a variety suitable to the locality; if ihe has also cultivated the : land well and taken care that the plants have a sufficiency of • suitable nourishment at their disposal, he can then anticipate with some confidence that he will harvest a satisfactory crop. A sufficiency of suitable nourishment. That is most important. How can it be best supplied? It must be remembered that the crop from start to finish is only about five months in the ground, and therefore the fertilisers should be furnished ; in a quickly-acting form, otherwise the crop will not be able to utilise them. If the crop be grown after roots fed on the land, or .any other heavilymanured crop, it should require the application of nothing except a little nitrogen, and this can be suitably given by a top-dressing of lewfc to l£cwt of nitrate of soda.

If, however, the crop is grown -after wheat or barley or a previous crop of oats, then it should have a liberal supply of suitable fertilisers, and the following dressing can be recommended:3ctwt of superphosphate mixed with lewt sulphate of ammonia at time of sowing, followed up when the plant appears above the ground by iewt to lewt of nitrate of soda. To top-dress evenly such a small quantity of nitrate of soda, it should be first mixed with some dry earth. If the soil in which the crop is grown is of a light kind, it will he wise to add to the superphosphate, and sulphate of ammonia a small quantity of sulphate or muriate of potash, £cwt of either should suffice, or 2cwt of kainit. ACID SOILS. As every farmer knows, the presence of acidity in a soil is injurious to vegetation. It gives rise to some well-known plant diseases, such as " finger-and-toe" in turnips, it prevents the growth of sweet rich herbage, and there are some plants, for instance, lucerne, that refuse to grow in acid soils. What are the principal causes of soil acidity ? 1. The decomposition of organic mattor accompanied by the formation of various organic compounds. > 2. The action of soil bacteria acting upon certain portions of the vegetable matter in the soil.

3. The breaking up of mineral fertilisers. Thus, when sulphate of ammonia is decomposed in the soil there is a formation of free acid in the soil solution, which is injurious unless counteracted by the presence of a sufficient supply of lime in the soil. It is possible that to the acidity so produced in the absence of adequate lime may be attributed the unsatisfactory results which have sometimes been noticed from the use of sulphate of ammonia in sandy, acid soils. 4. The fermentation of green materials. When a heavy crop of green material is ploughed under, fermentation will set in if . the conditions of temperature and moisture are favourable, and as a result the soil, may become sour unless it is well supplied with baseS such as lime, magnesia, etc. Experiments have shown that an acid solution exercises a toxic effect on plant life, which is injurious to the growth of nearly all the cultivated crops. Acid soils are infertile because soil bacteria, wliich are elaborators of plant food, cannot grow in them. A soil may be rich in nitrogen and contain sufficient minerals, but if it is waterlogged it is acid and sour, and will not produce good crops. If, however, this condition is corrected by drainage and aeration, it becomes a fit habitation for soil bacteria, and becomes productive. It is specially important that the soil conditions should be made ,as favourable as possible to the development of the nitrifying bacteria. The acids in the soil may also have the effect of bringing into solution minerals that have a bad effect on plants, as, for example, compounds of iron and alumina.

| Drainage is essential if the land is I waterlogged,,and the application of lime to neutralise • the . acids. Lime In one form or other - is, the remedy. It neutralises .sourness and prevents the formation of poisonous compounds in the soil. It, prevents fungoid diseases, and in pasture land promotes the growth of the more nutritive herbage. Basic slag owes much of its value to the lime in it, which produces a wholesome and sweet condition of the soil.

It would appear from the results of experiments that for practical farm purposes the neutralising effect of applied lime is not exerted below the depth to which it is incorporated with the soil during" the various processes of preparation and cultivation. Consequently, the more thorough and the deeper these operations are, the better the distribution and the more effective the action of the lime. The knowledge thus obtained on these points enables us to say that the incorporation of lime with 3in or 4in of surface soil is sufficient to produce marked effects on acid soils, and also that at any one time it is needless and possibly occasionally harmful, so far as the immediately succeeding crops are concerned, to apply more lime than will neutralise the soil to a depth to which it is to be cultivatedIt is the better farm practice, therefore, to apply only this amount of lime, and immediately after the next ploughing to repeat the application and work it in. These results indicate that alkaline soils are more fertile than acid soils, and produce crops more economically than acid soils do; that in applying lime the soil should finally be made alkaline to the full ploughed depth; that in ordinary farm practice the acids of the subsoil are. not neutralised by applied lime. ■ - * FERTILISER TERMS. In the minds of farmers who have little time to study the technicalities of nomenclature. confusion may easily, arise as to the precise meaning of . the different names under which phosphate of lime is offered for agricultural purposes. There are four forms of phosphate of lime:— Soluble in water, as in superphosphate. It is "mono-calcic," namely, one equivalent of phosphoric acid is combined with one equivalent of lime, and when phosphate of lime is described as "soluble," it is understood by long custom and usance in the trade to mean "soluble in water." This is recognised by tho Fertilisers and Feeding Stuffs Act, because in section 10 (1) we find the words, "The expressions soluble and insoluble shall respectively mean soluble and insoluble in water." and if the phosphate of lime is not soluble in water, but in citric acid, it should be so specified. 2. Soluble in weak acid, as in basic superphosphate, reverted or retrograde phosphate. This form is "di-calcic," that is, one equivalent phosphoric acid combined with two of lime. On the Continent and in America reverted ' phosphate,, holds a well-recognised place in the trade, : and value is attached to it. In this country at present it is practically ignored, which ;we think is a mistake, because it is a valuable 1 form, and a manufacturer is entitled to be paid for it. 3. Insoluble in water, as in. raw mineral phosphate, " tricalcic"—namely, one equivalent, of phosphoric acid combined with three of lime,' and' held so tightly as to be very slowly available; In raw mineral phosphate the phosphoric acid cannot be given any value except ■ for sdils • full of humic • acid, and' even then it is not worth using, ~ because, basic slag is better. The phosphate of lime in phosphatic Peruvian guano, bonemeal and bone-flour ,is partly tri-calcic, but, being organic in structure, is more useful. _ , 4. Soluble in 2 per cent, solution of citric acid, as in basic slag, known as citric soluble " tetra-calcic," namely,' one equivalent, of phosphoric acid • combined with four of lime, but combined so loosely that the phosphoric acid is very easily and quickly available as plant food. . The best basic slags contain 80 to 90 per "cent, of total • phosphate of lime thus soluble, and represent a highly efficacious.form of' phosphate. ' Such phosphate is "known in the trade as "citric soluble," to distinguish it from the soluble, phosphate, the term applied to water-soluble phosphate in superphosphate, bone manure, etc. , ;

PLANTS AS . GUIDE TO . SOIL., Different species of plants have varying soil requirements or plant foods in different proportions,- hence different plants abound end luxuriate in different localities , and soils arid, therefore, knowing from observation what soils suit certain plants best, ! we are able to argue back, to a certain, extent/ at any rate, as to what the quality and condition of the soil is in which we find peat-loving," chalk-loving, clay, or sandloving plants growing , profusely. . Thus,, then, it "is more or less true 'of all plants growing in a natural'state that they are "soil indicators, and from the special weeds of a district the. farmer may .be guided in his methods of soil culture For instance, few land - plants ; can stand stagnant water at their roots, therefore'when we find any of those plants that can flourish in such circumstances, such as wild mint - cuckoo flower, horse-tails, fleabane, or colts' foot, growing in V health and plenty," we may conclude that drainage is then and there required. : \ " " Similarly, if we . find, such lime-loving plants as dogweed, maple, spindle : wild cherry chicory, burnetii arid kidney vetch flourishing, we may be stir© that lime or chalk ,is present in ? ample . and available quantity, although our eyes may not bo able to detect any signs, of its presence upon the surface of the soil. On the other hand, there are certain plants intolerant of lime, or lime haters, and the presence' of these—sweet vernal grass, sweet chestnut, parsley fern, and bog and peat iriosses—• indicates that lime is deficient and should be applied for cultivated crops. ' Seaside pines and sweet chestnut grow luxuriantly in poor soil in chalk, -but are | stunted and soon die, branch by branch, on chalk. Sheep sorrel, bilberry, whortlo- : berry andfoxglove are also indications that the soil is • poor in lime. . <•; As ; a general rule, where 1 nettles, ptimroses, clover, sow thistles, and goosefoot are found to flourish it is a good sign for the agriculturist; but where crab grass sorrel, horsetail, coltsfoot, may weed and marsh rot abound there is something for j the farmer to farm, against. A blind farmer [was. once driven ; pjh«. son to look at a derelict farm. , Having arrived at their destination, he told the lad to tie the m, up to the - tallest thistle in the first field they came to. "There's plenty of dock* and water-grass father, but I can't see no thistles, said the boy; and this fact alone decided the blind parent against becoming a tenant of the land. 8 SOIL BACTERIA. The European agricultural scientists continue to devote attention to the influence of bacteria in the soil, with the object of discovering the causes of greater or less activity, and the most effective way of encouraging these organisms to work for the benefit of the crops. Well-cultivated sou with a fine tilth possesses greater bac- i terial activity than a soil full of clods. A well-aerated soil containing organic substances encourages the development of beneficial bacterial activity. The • appli- 1 cation of sulphate of ammonia, sulphate of magnesia and superphosphate appear to be helpful to bacteria, and especially is this the case with ammonia salts. A sufficient amount of moisture in the soil combined with aeration and organic substances, are the most favourable conditions. The lower layers of the soil do not favour the existence of bacteria. In this respect deep stirring of the subsoil without bringing it to the surface is advantageous, by permitting air to percolate downward. The presence of lime, rendering the soil alkaline, is beneficial, indeed essential. The most favourable conditions for bacteria are simply those which all intelligent farmers try to obtain, viz., good tilth, deep stirring, admitting air, organic matter, and sufficient lime.