Structural Differences among Fibers from Six Cultivars of Harakeke (Phormium tenax, New Zealand flax)

Abstract

The microscopic structure of muka (fiber aggregate extracted from harakeke) (observed using light microscopy and scanning electron microscopy) from six selected cultivars of harakeke varied, and this may explain the differences perceived by weavers, and that different end uses are preferred for various cultivars. The dimensions of ultimate fibers ranged from 10.1 μm (Takaiapu) to 12.8 μm (Paretaniwha) in average-transverse-width and 3735 μm (Takirikau) to 4751 μm (Makaweroa) in length. The cultivars prized for muka (e.g. Arawa, Makaweroa) had the longest and finest ultimate fibers. The transverse-section shapes of fiber aggregate bundles varied among the cultivars. Tapamangu and Takaiapu had fiber bundles that were more uniformly shaped than the other cultivars studied, and Takirikau had a high yield of fiber aggregate bundles. Paretaniwha differed from the other five cultivars studied having an average number of narrow, non-uniformly shaped fiber aggregate bundles per unit width.