Growing Linseed

New Zealand Journal of Agriculture, Volume 81, Issue 5, 15 November 1950, Page 441

Growing Linseed

By

J. D. WRAIGHT,

Fields

Instructor, Department of Agriculture, Timaru. f T"*HE growing of considerable -®- acreages of linseed, mainly in the arable areas of the South Island, has been an important feature in the cropping programme of New Zealand for many years. The area of linseed grown has fluctuated considerably in the past. Over 10,000 acres were grown in the 1922-23 season, under 1000 acres in several years between 1936 and 1943, arid the acreage is now in the vicinity of 20,000. THIS variation was brought about, by an unstable market which was governed mainly by the overseas price and demand for linseed and linseed oil, which had the effect of making the growing of linseed attractive to the farmer only in years when world prices for the product were high. At one time. a linseed oil extraction plant operated at Auckland, but because of lack of assured supplies of linseed for processing, the project was abandoned. However, during the Second World War seed from the linen flax industry began to accumulate and in 1943 a factory for expressing oil from this seed and treating by-products was established in Dunedin. As this factory has definite annual requirements of seed in excess of that available from the linen flax industry,, the linseed crop is now contracted for on a fixed basis, with certain premiums payable to the grower for varying qualities of seed. This price is stable and the crop can now be regarded as financially as secure as any other of the ■ spring-sown crops such as spring wheat, oats, barley, or linen flax. As the seed contains on an average approximately 36 per cent, of oil, each ton of seed produces 75 to 80 gallons of oil. The types of oil produced in New Zealand from locally grown and imported linseed are raw, acid-refined, alkali-refined, boiled oil, double-boiled oil, pale boiled oil, stand oil, and blown oil. i The effect of the recommencement of linseed oil extraction and the consequent demand for supplies of raw material can be seen in the table below.

Extent of the Crop As better cropping conditions prevail in Canterbury and the linseed crop fits in very well with a fully arable programme, the greatest acreage of linseed , is grown in that province. Of the Otago acreage about 500 acres are grown annually in North Otago and 200 to 300 acres in South Otago. In Southland the main linseed areas are eastern and western Southland, each area growing about 500 acres annually. In the 1947-48 season 54 per cent, of the total linseed acreage in the Canterbury Land District (16,087 acres) was grown in North Canterbury, 34 per cent, in Mid-Canterbury, and 12 per cent, in South Canterbury. Soil Types As linseed is primarily a springsown crop, the growing of it fits in very well in those areas where it is not always possible to get land ready for wheat or other cereal crops in autumn and winter because of wet conditions or because lea land requires longer cultivation. For these reasons

it is an excellent pilot crop on the browntop lands of the foothills. Where the crop is used for this purpose it leaves the soil in excellent mechanical condition for the growing of a cereal crop after the linseed. In North Canterbury about 500 acres per year are grown by contractors on a share basis on this type of land and to the farmer it is a means of getting his land cultivated with a minimum amount of work on his part, as the contractor attends to the cultivation and harvesting. In other areas in Canterbury the linseed crop is not confined to the foothills, but is grown mainly on clay downs, with some areas on the bettertype stony soils. The heavy, rich soils are not suitable for linseed growing, as growth is usually excessive under these conditions, ripening tends to be uneven, and the crop presents many harvesting difficulties. On the poorer stony plains soils growth conditions are not good, yields are low, and the crop is uncertain. In Otago and Southland the crop is grown under a variety of conditions: On land suitable for wheat in North Otago, on the clay loams of South Otago, and on the better-drained clay loams ■ and ’ gravel subsoils in Southland. Cultivation In most districts linseed is grown on land which is cultivated out of old run-out grass and this calls for some preliminary preparation such as grubbing or hustling the lea paddock or skim ploughing before the main

ploughing. It is essential to avoid hollows under the furrows, and such preliminary work is the one way in which this can be achieved. Recently the digger plough has become -popular for this work, as the skimmer places the edge of the furrow down at the base of the turned furrow and so achieves the same object in one operation. Also the quick-turn board of the digger plough fractures the furrow and so reduces the amount of subsequent cultivation required by discs or other implements. The cultivation of linseed calls for only a medium depth of ploughing (4 or sin.) and it is most important to get a good crumbly tilth, not a fine floury tilth, which sets badly with heavy rains and hinders the growth of the crop. To obtain a crumbly tilth early preparation is necessary, as late ploughing usually means hurried final preparation and consequent fineness of tilth. In some southern districts, notably western Southland and South Otago, the crop is more likely to follow turnips, and preparation of such land for the linseed crop starts immediately after the turnips nave been fed off. Fertilisers Although many manorial trials have been laid down by the Extension Division to determine the manurial requirements of the linseed crop, no definite information has been secured on manurial recommendations. In districts where the sowing of superphosphate is general with cereal and other crops this fertiliser is sown with linseed, as it is considered that it helps in the initial establishment of the crop. Applications vary from lewt. per acre in the Canterbury district to

2 to 3cwt. per acre in Otago and Southland. It is generally found that linseed does not respond to lime sown with the crop, but does better on soils which have been limed well during their period in pasture. Like other crops, linseed gives better returns on land which has been improved through the growing of good , pastures, and it is felt that the residual effect of phosphates and lime applied to those pastures and the general rise

in fertility of the land are responsible for the increased yields now being obtained. Varieties Of the seven harvested spring-sown trials in the 1948-49 season, good results were secured, which enable the following comments on the behaviour of the varieties of linseed to be made. Golden Viking and Victory have been outstanding in yield preformance and desirable agronomic features. The former matures earlier and has somewhat shorter straw; both are rust resistant, have large bolls, and are attractive in appearance. Koto was the most impressive variety, but has not yielded as well as Golden Viking or Victory except in the trials in Southland and Willowby (Mid-Canterbury). It matured early and was of moderate height, but it had small seed bolls and this may have been the cause of its relatively lower yield. Walsh has yielded relatively poorly and appears to be of uneven type; it would seem that this variety could with advantage be replaced by Golden Viking and Victory. Punjab has been low yielding and its extremely short straw and tough seed bolls make it difficult to harvest. It appears to be unsuitable for New Zealand conditions. In one trial in South Canterbury Cheyenne yielded poorly, although it was most attractive in early growth. Bison yielded well in one trial in Southland. Other varieties such as Rio, which showed promise of rust resistance, N.Z. Commercial Register, Royal, and Red Wing have been dropped from the trial because of low yield or other disadvantages. In practice Golden Viking has proved to be a very suitable variety for the Canterbury and North Otago

districts and the bulk of the area contracted in these districts was sown with this variety. In Southland Bison is preferred, owing to its early maturity. At present the choice of variety is to some extent limited by the availability of seed, but every endeavour is being made to have available supplies of seed of the varieties proving most suitable to local conditions. Rates of Seeding During the 1946-47 season trials were laid down to get information on rates of seeding. The trial was conducted in three widely separated districts, Swannanoa, Winchmore, and Kakapui, and included the varieties Bisori, Walsh, Rio, and Golden Viking, sown at rates as low as 411 b. per acre to as high as 1701 b. per acre. ■ Yields from the low rates of seeding averaged 12cwt. per acre and from the high rates of seeding 12.1 cwt. per acre, there being no significant difference in yields brought about by high or low seeding rates. In practice 301 b. to 401 b. of seed per acre (varying according to germination capacity and seed size) are sown on the lighter land; on heavy soils 551 b. to 701 b. of seed are sown per acre. Sowing The crop is usually drilled through 7in. coulters and care must be taken that the seed-bed is firm to ensure even depth of sowing, as the seed is fairly small and a quick strike is desirable. To achieve this drilling should be carried out on a rolled surface and it is necessary for the soil to have been well consolidated throughout the earlier cultivations. If possible the coulters of the drill should be set in line and turnip coulters or well-worn coulter tips should be used to ensure that the seed is not placed

too deeply. The depth of sowing should not be greater than lin. It is not usual to harrow after sowing, as heavy grain harrows tend to put the seed in too deeply. Sowing should be completed in October to avoid late harvesting. Diseases and Weeds Rust is the most serious disease of linseed. The rusts found in cereals and ryegrass, though related to those of linseed, are different strains of the fungus and cannot be transferred. The existence of various rust strains complicates the problem of obtaining varieties of linseed resistant to rust. In testing for rust susceptibility it has been necessary to collect samples of rust from all parts of New Zealand,' as it has been noticeable that though some varieties of linseed are practically free from rust in Southland, they may be severely affected in North Canterbury. This may be due to different strains being , active in different districts. The spread of rust in a crop is favoured by damp weather and in cases of severe infection yields may be reduced by as much as 75 per cent. It has been found that autumn-sown crops are more severely attacked by rust than spring-sown crops, and when there are autumn-sown crops in a district they provide a means of overwintering the fungus and allowing early infection of spring-sown linseed. Browning or stem-break causes damage in some seasons, but it is not considered a serious disease of linseed. A disease called pasmo has appeared in some linseed crops, affecting large areas of the crop and hastening the maturity of the affected areas. In spite of fairly bad infestation, seed yields were not appreciably lowered by this disease. Weeds: Most of the linseed is grown on clay downs country where the

most serious weed affecting the crops in the young stages is spurry. This weed tends to choke the young seedlings and even when cultivation is properly carried out it may be serious, causing greatly reduced vigour in the crop and lowering yields.

Fat-hen may affect the crop at a later stage and can cause reduced yields. In most cases, however, it is not regarded as being as important as spurry.

Redshank is a troublesome weed in some areas, as the seed of this plant is very difficult to dress out of linseed.

Harvesting

The old method of cutting the crop with the binder, stocking, and threshing out of stock or stack is not used to any extent with the linseed crop, except in Southland and Otago, where bad weather may hold up other methods of harvesting. In the lowerrainfall areas of Waimea, North Otago, and Canterbury direct heading of the crop is largely practised, provided there is no excessive weed growth or second growth of the linseed itself.

For direct heading weather conditions must be good, as hot, dry days are necessary; any slight increase in humidity makes the crop very tough and difficult to thresh and harvesting under such conditions may cause the seed to be severely damaged.

Many growers prefer to cut the crop with the mower or to windrow it by a binder and some days later to pick it up and thresh it through a header.

The last method gives better results under, difficult conditions than does direct heading.

Yields

Yields vary considerably with conditions, for it must be remembered that all the linseed crop is not grown under ideal soil and climatic conditions, and whereas yields of up to 1 ton per acre are secured from suitable land, yields of as low as 3cwt. per acre are obtained from poorly cultivated soils under unfavourable conditions. The average yield in Canterbury is about Bcwt. per acre, in North Otago 6 to Bcwt. per acre, and in Southland 10 to 12cwt. per acre.

Position Today

. The linseed crop fills an important place in the cropping programme in the drier arable districts of the. South Island, both as a cash crop to the farmer and also as a pilot crop preparatory to wheat or other cereals or for the establishment of pasture. Investigational work on varieties, rates of seeding, fertiliser applications, and weed control is proceeding in cooperation with farmers in an effort to solve some of the problems of growing the crop and attention is being given to diseases which affect it.

The growing of linseed is now established in the cropping districts and every effort is being made to supply the farmer with all the information which will enable him to make the growing of the crop a success financially. and agriculturally.

BEHAVIOUR OF VARIETIES OF LINSEED

HARVESTING OF LINSEED

1947-48 Canterbury Otago Southland Other districts N.Z. total .. 16,087 1,266 1,178 197 (Marlborough) 18,728 1946-47 10,74! 625 926 — 12,292 1945-46 8,927 926 505 3 (Wellington) 10,361 1944-45 3,640 336 348 2 (Marlborough) 4,326 1943-44 702 123 404 J 1 (Marlborough) 1 33 (Nelson) 1,263 942-43 81 78 195 __ 354 354 1941-42 387 185 269 18 (Wellington) 859 1940-41 1,194 90 — — 1,284

LINSEED ACREAGE GROWN IN VARIOUS DISTRICTS