Improvement of Inferior Swards on Wellington Hill Country

New Zealand Journal of Agriculture, Volume 87, Issue 2, 15 August 1953, Page 161

Improvement of Inferior Swards on Wellington Hill Country

IN the Wellington hill country on both sides of the Pukerua Bay-Plimmerton main highway, on many areas adjoining both basins of the Porirua Harbour, in the lower Horokiwi Valley-Pauatahanui-Judgford area, and on portions of the hill lands of the Moonshine Road from Judgford to Upper Hutt there are considerable areas of terrace, rolling, and semi-steep hill lands which are carrying inferior pasture swards and which are capable of considerable improvement. This article by J. M. Hopkins, instructor in Agriculture, Department of Agriculture, Levin, refers in particular .to methods adopted to improve those inferior • swards on farms in the Horokiwi Valley-Pauatahanui-Judgford area and on the Moonshine Road between Judgford and Upper Hutt.

THE practice of cultivating hill lands and bringing them into better pasture is in no way unique. It is. however, of such outstanding success in these districts in changing the low-producing, inferior swards to high-producing types capable of fattening stock that this recording, of the methods adopted is considered to be well worth while. Pasture Renewal Methods On the inferior hill swards of this area pasture improvement may take place through oversowing or after a planned cropping programme. In the former. method considerable improvement can be effected by combining an oversowing of subterranean clover or white clover with phosphatic topdressing. The method, however, is much slower than the cropping method. Consequently it should be restricted to steeper areas where cultivation would be too difficult or dangerous.

Under the cropping method the first job is to disc the area with giant discs as soon after winter as the country can be worked, usually early in August. After 6 to 8 weeks, during which weathering action will have broken down much of the rough, disced turf, a further double cut by heavy discs will break down the soil, so that, after harrowing and rolling, a fairly good seed-bed will be ready by late October. If desired, heavy levelling irons may be used to crush clods and assist in levelling the surface before harrowing and rolling. The initial crop on such country is usually swedes or turnips sown for early to later winter feed.

Superlative swedes or Hardy Green Globe turnips are the most popular varieties and are usually sown at lib. per acre with 3 to 4cwt. of superphosphate, serpentine superphosphate, or a proprietary mixture. After these crops are fed off, the land is occasionally returned to grass in spring. . This entails a further double discing with tandem discs in August, followed by harrowing and rolling to have the land ready for grass seed sowing by mid-September. More frequently, however, the areas are cropped again before being sown to pasture in autumn. In such cases the same spring cultivation is given, with the final working down taking place in time to allow the areas to be sown in rape during October. For this purpose Broad Leaf Essex is generally favoured at 31b. per acre with 3cwt. of equal parts of superphosphate and blood and bone. When this crop is fed off, the land is again double disced in February, harrowed, and rolled, to be ready for grassing by late February or early March. Farmers appreciate the value of good seedings with high-quality seed, and consequently there is a demand for Certified seed in all grass mixtures. One that is commonly sown is as follows: lb. per acre Certified perennial ryegrass 25 Certified short-rotation or Italian ryegrass . . .5 Certified white clover . 3 Certified Montgomery red clover .. 2 Certified Mt. Barker subterranean clover 2 Certified cocksfoot . . . 5 Certified crested dogstail . . 2 44

With this seeds mixture it is customary to sow 3cwt. of superphosphate or serpentine superphosphate. In addition it is found that a further 2 to 2jcwt. per acre, sown in the first spring after establishment, strengthens the clover growth and ensures that the pasture will be a success. The cropping programme as outlined provides a useful supplementary feed supply.

The hard turnips and swedes are particularly valuable in the early stages of transition from poor swards to good pastures, as they supply a much-needed addition to the inadequate winter growth from grass. Consequently the main flock sheep and breeding cattle can be carried over in better condition. Likewise, the second crop, rape, provides a valuable addition to the available summer feed and assists with the fattening of lambs and dry sheep. In addition to these advantages from cropping, mechanical cultivation of the soil improves its tilth and permits uneven surfaces to be levelled before permanent grassing is done. Furthermore, the feeding off of all crops raises fertility through the concentration of stock droppings. This is of considerable benefit in the early stages of establishing pasture. Management of Improved Areas Under a system of improvement which involves cropping on relatively small areas the essential fencing into suitably sized fields is often done to provide protection for crops. Consequently further subdivision is not always necessary. However, the value of reducing the sizes of large fields to enable better grazing management to be practised should never be, overlooked. At present fencing on hill country is costly both for material and labour, and further subdivision may not appear warranted. The point to remember, however, is that highproducing pastures will remain so only if well managed, and good management is difficult on large fields. Hence subdivision should be provided for in any scheme for pasture renewal and improvement. There is a tendency to punish improved pastures by overgrazing, especially where the areas are limited in

the early stages of improvement. This must be avoided at all costs,. and a well-ordered system of . alternating grazing and spelling should be developed in conjunction with the general grazing of the whole farm. This ensures that adequate spells for recovery after grazing will be provided. In addition, all new areas should be. topdressed annually. Generally 2 to 3cwt. per acre of phosphate applied in autumn will be adequate, and in practice superphosphate, serpentine superphosphate, and occasionally a proprietary mixture are applied at this rate. ■ Provided some attention has. been paid to levelling and adequate tracking has been provided, a considerable proportion of this annual topdressing can be done by ordinary manure distributors. Where this .is impracticable the fertiliser can at least be hauled by tractor to suitable points for hand application. Recently there has been much more attention given to aerial topdressing, and it is expected that much of this country will be topdressed by plane in the near future. Effects on Production Improvement of hill swards is usually reflected in improved quantity and quality of farm products and in a higher carrying, capacity. The first noticeable effects come fromgreater wool and meat production, even

though the total number of stock carried does not rise immediately. In a relatively short period, however, it is found possible to increase stocK numbers as well and still maintain the higher level of production. To illustrate these points the following information concerning farms at Pauatahanui is given. The first example is a farm of 500 acres of semi-steep hill country, which was acquired in 1946. The country was grossly overstocked, consisted mainly of chewings fescue-browntop-danthonia pasture, and had never been topdressed. The earlier carrying capacity is unknown, but the owner could not carry more than 368 ewes with 325 lambs in 1947. At this time the wool production was 11 bales. By the end of 1952, 169 acres had been cultivated, cropped, and sown to new pasture and the carrying capacity was then 310 2-tooth ewes, 865 breeding ewes with 869 lambs, and wool production was 30 bales. New grass areas on this farm now carry 3 ewes per acre, whereas the original sward would not do better than one ewe. Expressed in terms of money the value of one acre’s production in 1947. represented by the - lamb and wool from one ewe, was £3 Bs., but an acre of new grass in 1952 carrying 3 ewes returned £l5. . On another area of 280 acres the stock carried before pasture improvement were 330 ewes, 50 ewe hoggets, and no cattle. Today, after regrassing of the area, the winter carrying capacity is 700 ewes, 200 ewe hoggets, and 70 young cattle. Apart from increased numbers, the health and vigour of stock have improved, wool weights are up, and all surplus lambs are fattened off their mothers. On a third farm, recently acquired, one field has been cropped and regrassed, and the carrying capacity has risen from 1 ewe to 4 ewes per acre. Many similar instances could be cited, but these will serve to confirm the striking influence such pasture improvement can have on farm production. Considerable Improvement Possible Tn Hutt and Makar a Counties rhe extent of country which could be improved by these methods is considerable. In the past most of such work has taken place on the easier terraces and rolling country, but, with the provision of better tracks to the higher country, operations are now expanding on to this land. Aerial application of fertiliser and seed will play an increasingly important part in the further development and maintenance of such country—factors which will lead to greater increases in flocks and herds with resulting improvement in production of wool and meat, as well as breeding stock for the lowlands. Higher production from farmlands is an urgent requirement, and this can be accomplished in a big way by concentration on the development of hill country. . - . In the Wellington district alone the application of approved methods of development to hill country could have a striking effect on production, an effect that could be multiplied many times if extended generally to the hill country of all districts in the North Island.

Bulletins for the Hillcountry Farmer HILL-COUNTRY farmers will find interesting and useful the Department of Agriculture bulletins listed below. Except. where otherwise stated, all the bulletins are free and are available 'at offices of the Department. The chargeable bulletins are available at main offices only. No. 189 Control of Internal Parasites by Phenothiazine. 192 Blowfly Strike in Sheep. 234 Shearing Machines. 240 Lime Requirements of Soils/ 246 Shearing, 6d., post free. 249 Killing Your Own Meat, 6d., post free. 308 Rearing and Training a Sheep Dog. 316 Weed Seeds in Agricultural Seed. 325 Foot-rot in Sheep Can Be Eradicated. 328 Foot Troubles in Farm Animals. 329 Chemical ■ Methods of Weed Control. 339- Developing Marginal Lands, 10s., post free. 348 Lambing Troubles. 353 Design and Construction of Sheep-drafting Yards.