NEW ZEALAND FLAX (PHORMIUM) REFUSE.

New Zealand Journal of Agriculture, Volume VI, Issue 1, 15 January 1913, Page 16

NEW ZEALAND FLAX (PHORMIUM) REFUSE.

ITS MANURIAL VALUE.

B. C. Aston,

F.1.C., F.C.S.

New Zealand flax-refuse is the fleshy portion of the leaf of Phormium tenax, with some short fibre. The refuse accumulates as a waste product in the process of producing the fibre variously known as New Zealand flax, New Zealand phormium, or New Zealand hemp.

Dr. Purchas, of Auckland, .in 1868 (Trans. N.Z. Inst., Vol. i, p. 69) stated that the refuse made “ most excellent food for cattle.” Certainly the well-chewed ends of flax-plants are evidence' that stock to some extent find the leaf palatable, but I am unaware that any exact experiments have been carried out to show its food-value. A farmer who is grazing cattle on large areas of drained flax swamp in the Auckland Province informs me that he is positive that cattle eat the growing flax even when there is abundance of good grass available. Sir James Hector (“ Phormium Tenax as a Fibrous Plant,” 1889) mentions that if cattle have access to a field of flax which has been cut they will destroy the plants altogether by drawing, out the young’ leaves to chew the butts, of which they- are very fond. The same writer suggests that if the sodium-sulphite process be used to obtain the fibre the rejected portions of the leaves could easily be converted into papermaker’s pulp. Professor A. H. Church (now Sir Arthur) some forty 'years ago (Trans. N.Z. Inst.', Vol. vi, 1873) conducted a research of the chemical composition of the phormium-leaf, and suggested that the ash of the refuse would make a lye to be used for the partial cleansing of the fibre;

Seeking for a substitute for stable manure, a difficult substance to obtain in this country, where there is so little stall-feeding of stock, some years ago I suggested to Mr. J. D. Ritchie the advisability of experimenting with New Zealand ' flax-refuse, a complete analysis’, of which is. given in my Annual Report for 1900 (see pp. 135-6, N.Z. Dept. Agric. Annual Report, 1900), and a partial one in my 1904 report (p. 137). Experiments were accordingly carried out at the Weraroa (Levin), Ruakura (Hamilton), and Moumahaki

Experimental Farms. On a clay soil' resting on gravel, at Levin, potatoes were planted on the sth October, and on the 6th November 2-19 in. of rain fell in fourteen hours. In these trials 5 tons of Upto-Date sets, sown with no other fertilizer than flax-waste at .the rate of 30 and 20 tons per acre, came away fully a week in advance of crops fertilized with artificials only, the former maintaining their growth right through the season. The 20 - ton - dressed plot gave a crop of good quality, but not equal to that given by 2 cwt. superphosphate ; the 30-ton-dressed plot was very much better, being • quite’ equal to the best of the artificially dressed plots (1907 report, p. 320). The Overseer, Mr. Drysdale, remarked that thousands of tons of this valuable refuse which could be made profitable use of were lying about unutilized at the various mills.

At Ruakura, on a sandy soil, 20 tons of flax-waste, without any other fertilizer, gave an increase of 2 tons 7 cwt. of potatoes over the unmanured plot—a profit of £6 19s. per acre due to the waste, after allowing 2s. 6d. per ton for cartage. The. waste was valued at 2s. 6d. per ton (see Journ. Dept. Agric., Vol. i, No. 4, pp. 275-6), this being the actual cost of carting and distributing. . The following are the actual results :

In order that it might be certain that no mistake had been made with reference to cost of carting and distribution of the waste, the matter was referred to Mr. Primrose McConnell, the farm manager at Ruakura, who replied that, in his opinion, 2s. 6d. per ton would in that instance cover the cost of carting and spreading, the charge being quite a fair one (the paddocks were comparatively near the flax-mil]). Probably the profit would have been much greater had 30 tons instead of 20 tons been used. .

As was to be expected, the flax-refuse by itself did not show up very favourably with this crop, but when combined with superphosphate, 2| cwt. per acre, the treatment produced 70 tons of mangels at a cost of 4|d. per ton for fertilizer, and took second place in a trial with twenty-two ' different mixtures of artificial fertilizers, 5 cwt. of basic slag per acre taking first place and producing a crop at a cost of 4d. per ton.

Comparing flax-refuse with stable manure, it may be said that while containing similar amounts of water and phosphoric acid the refuse contains larger amounts of potash and nitrogen. It has,, moreover, one very great advantage over stable manure inasmuch as it does not contain any weed-seeds, a fact which ~ will appeal to the farmer.

Unfortunately, experiments on State farms do not always carry the weight with the average farmer that they should. There is perhaps the suspicion that the State' farmer is able to employ means which are not within the reach of the ordinary farmer to ensure favourable results. One. experiment in the Waikato by a flax-miller may therefore be quoted as showing the practicability, of using the refuse as a manure. This gentleman used a heavy dressing of the refuse, ploughed in, and had a very heavy crop of pumpkins* as the result, no other fertilizer being used. He was quite satisfied with his experiment. Following the pumpkins a crop of oats was grown, with 2 cwt. bonedust and superphosphate ; the crop was very good. Grass with 3 cwt. bonedust followed, and the pasture was all that could be desired. This gentleman made use of all the refuse, most of it being just spread on the. grass paddock as a top-dressing, the results being highly satisfactory.

“ J. W.,” Waimea West, writing to the Journal of the Department in January, 1911 (p. 52, Vo], ii, No. 1), says, “On my farm a few years ago a flax-mill was working, and where the pulp was scattered over the ground the corn grows and yields better than elsewhere.' 5

It seems desirable that experiments should be made with highpriced crops like potatoes on land near flax-mills to ascertain if the waste could be profitably utilized.

* When potatoes are selling, as at present, for £8 per ton the actual gain from the manuring would be increased twofold.

* The efficacy of flax-waste as a manure for pumpkins is also vouched for by a well-known Manawatu farmer.

— 20 tons Refuse. 10 tons Refuse, 2 cwt. Bonedust, 2 cwt. Basic Slag. Cost of manure ., £2 10s. . £2 Os. 6d. Yield per plot .. 1 ton 19 cwt. Yield per acre .. 10 tons • . 9 tons 10 cwt. Increase over unmanured, per acre 2 tons 7 J cwt. 1 ton 17 J cwt. Value of increase at £4 per ton* .. £9 9s. ' £7 9s. Profit per acre, due to manure .. £6 19s. £5 8s. 6d.

■ — • 2J cwt. Superphosphate, 28 cwt. Flaxwaste. 56 cwt. Waste. Cost per acre .. £1 6s. 6d. £1 8s. Yield per acre (roots) 79 tons cwt. . 15 tons 8| cwt. Yield per acre (tops) .. .. 9 tons 7J cwt. • 4 tons 10 cwt. Increase over unmanured, per acre 70 tons 11| cwt. 7 tons 6 cwt. Cost per ton of increase 4-id. 3s. lOd.

An experiment was also made at the Moumahaki Farm by Mr. Gillanders, on a crop of mangels, with the following results (see 1907 report, p. 309).