FERN AND BLACKBERRY.

New Zealand Herald, Volume LXVIII, Issue 20761, 2 January 1931, Page 14

FERN AND BLACKBERRY.

EFFECTIVE CONTROL. MARLBOROUGH EXPERIMENTS. BUSH LAND FARMING. Mr. A. G. Elliott, Instructor in Agriculture, Fields Division. Blenheim, gives the following account of the system developed hy Messrs. Harvey Brothers, at Mannroa, Pelorus Sound, for the control of fern and blackberry on hill country. The system may bo held to apply to the Marlborough Sounds generally and to many othei districts. The laud held bv the Harvey Brothers is roughly 3500 acres in area and of this 1500 acres are still in standing bush, consisting of rimu, matai, tawa. hinau, and pukatea, with typical undergrowth, and carrying red beech ("brown birch ) on the harder ridges. Of the 2000 acres which wero burned and surface-sown about 20 years ago roughly 100 acres are ploughable, and comprise a fan-shaped area fronting Pelorus Sound and into which the two main valleys open The hill country rises to an elevation of about 2000 ft., and is made up of approximately oqual areas of sunny, and shady faces.

It, is on blocks of this country that the invasion of bracken hard-fern and waterfern with, blackberry forced the farmers into the present method of control of this secondary growth. On two blocks, ono of approximately 100 acres and another of 150 acres, both of sunny aspect, the bracken was a solid mass 4ft. in height with large scattered clumps of blackberry through it, and with hard-fern and water-fern well established in shaded places around stumps and beside logs. The average annual rainfall rate of the locality is approximately 63in. Method of Farming.

At last shearing 27C0 sheep were shorn on the property, and the average weight of fleece from these Roniney crossbreds was 81b., while the average lambing percentage for the year was 90. All sheep wcro in good condition, and the prices for lambs were equal to the best in this part of the Sounds. A few head of cattle were run, but these are not important factors in secondary-growth control in this district, as will be shown. In 1910 an area of approximately 1800 acres, of which 500 acres were in sur-face-sown grass, was taken up and was then carrying 700 sheep. Bracken became established in the small valleys and gradually invaded the open areas, and to cope with this the old method of burning the fern and grazing it. with sheep and cattle was tried, but without success. In order to carry the sheep the flats were ploughed and sown in permanent pasture, and more bush was felled. It was soon realised that control of secondary growth on the fiats presented no great difficulty, but that some better method for dealing with the hi'.l country had to be evolved, as by this time the fern and blackberry had secured a good hold on those areas. An Effective Clearance. In 1914 a further block of 900 acres, of which 700 were felled and surface-sown and carrying 600 sheep, was taken up, with a result that that year the farmers had 1300 slice.p averaging a 61b. fleece uitli a lambing percentage of 87. During the next ten years burning-off of fern and blackberry, accompanied by a small amount of surface-sowing, was continued with but. little success. Whole blocks which formerly carried one sheep per acre were at the cud of ten years producing nothing but secondary growth. In 1924 a reverted block of 35 acres of shady face was tackled; the heaviest blackberry clumps were chopped down,, and the whole burned off during the first week in March. The area was then sur-face-sown with a mixture of perennial ryegrass, crested dogstail, brown-top, and white clover. During tho winter it was lightly stocked with one sheep per acre, but during the summer carried three sheep per acre, and now does this regularly from October until the f.ncl of February. At present the constituents of the pasture are brown-top, crested dogstail, white clover, suckling-cloyer and Yorkshire fog, with winged thistle and hydrocotylo in patches. The only traces of fern are in places inaccessible to sheep under the edges of logs, and there has been quite an effective clearance of blackberry. On all these areas tho actual control of the young fern on the nurn is done by hoggets, which are bought in when required and sold forward. For the last three years they have been disposed of at a profit of 2s per head, but it is obvious that their real value lies in secondarygrowth control. The cattle merely have access to tho blocks during the winter, but are not shut in on any of the areas as a definite factor in dealing with fern and blackberry. Main Points Summarised.

The iniiin points in the system practised bv the Harvey Brothers are as follows: — (1) Allow secondary growth to get away for ::t least three or four years, so that a good burn may bo secured. By this time the soil is opened up by the fern-roots, and with the ash secured from Ihe burn a good seed-bed results. At Manaroa burning is done during the first two weeks in March.

(2) Cut all largo bushes of blackberry to allow sheep to get among the burnt sticks to graze on young shoots and sur-face-sown grass. The cost of blackberry cutting is approximately £2 10s pel* acre. (3) Sow up to 121b. per acre of a grass mixture consisting of cocksfoot, danthonia, Chewings fescue, perennial ryegrass, crested dogstail, and white clover. (4) Depending on tho season, graze lightly with hoggets about two months after sowing, and increase the stocking until the.growth is held. Grasses are not allowed to seed and tho young fern and blackberry is nipped off early. The average spring and summer stocking at Manaroa is three and a-half sheep per aero up to tho end of February. Bought-in hoggets are held on tho new'blocks and remain there through tho winter. (5) The cheapness of the method is obvious, as country originally carrying one sheep per aero and Inter reverting to fern can in two years, with an expenditure of 8s per aero for seed, to which should bo added 2s per acre for sowing, bo brought back so that it can do two sheep per acre well. Tho bought-in hoggets, used solely for secondarygrowth control, are sold at a profit. z (6) The method has proved successful for handling fern and blackberry on both sunny and shady faces. Sheep will not eat either tho hard-fern or water-fern, but at Mannroa so far such good burns have been secured that the recurrence of these growths has not proved a problem. The water-fern disappears when its shelter is burned off, and if the hard-fern reappears'it can be dealt with by piling rubbish on it and burning it off with a, hot fire. Such areas will again be surface-sown with the mixture "already specified,'