Agronomic studies of flax (Linum usitatissimum L.) in south-eastern Australia

This paper reports on field agronomy studies into flax (Linum usitatissimum L.) conducted in Tasmania, Australia from 1994 to 1997. These studies inve stigated the performance of selected cultivars, and responses to sowing dat e, plant density and irrigation. The work formed part of a feasibility stud y assessing the potential of fibre hemp (Cannabis sativa L.) and flax as so urces of fibre for the Australian newsprint industry. Two cultivar evaluation trials were conducted at the University of Tasmania Farm, Cambridge, in Tasmania's south-east. One of these included 7 Europea n and Australian flax cultivars, and the other, 4 mucilage linseed cultivar s. The European flax cultivars yielded significantly more stem and bark fib re than the Australian flax cultivars. Of the former group, Ariane (841 g/m (2)) and Marina (883 g/m(2)) performed the best in terms of stem yield prod uction, while Viking had comparable bark yields to these 2 cultivars. With the exception of cv. Kreola (543 g/m(2)), which produced comparable stem yi elds to the Australian flax cultivars, the linseed cultivars were short and produced relatively low stem yields. Interestingly, seed yields (149-194 g /m(2)) were not superior to those for the flax cultivars (156-218 g/m(2)). While offering little dual-purpose seed/fibre potential, they may supply a future niche market for seed production. Three other trials were conducted to investigate the response of flax to se eding rate and sowing date, and the interactions between seeding rate, sowi ng date and irrigation availability. Autumn sowings of flax gave higher yie lds of both stem and seed compared with winter and spring sowings. Reasonab le stem and seed yields were achieved from dryland cropping of flax. Howeve r, good results from such rainfed crops in Tasmania will depend on autumn s owing and good rainfall during winter and spring seasons. There were clear yield benefits from irrigation between early November and January, when the amount and distribution of rainfall was poor. The selection of an optimum seeding rate will depend on the sowing date and involve a compromise betwee n maximising yield and minimising potential losses from lodging. The decrea sed occurrence of lodging with winter and spring sowings in this study, sug gests that later sowings can accommodate higher seeding rates.