Seed germination is poor in species of the nut-fruited Restionaceae. Investigations of seed morphology and development, seed collection and sorting, and seed viability were conducted in species of Cannomois Desv., Hypodiscus Nees and Willdenowia Thunb. to supplement existing knowledge, and to determine whether poor seed quality resulted in the poor seed germination identified in previous studies. Suitability of collection methods and the effectiveness of sorting techniques were evaluated using

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... -radiography. Shaking and ground collection methods yielded consistently higher proportions of full seed than extracting seed from cut shoots. However in species with bony bracts and few seeds per plant, the cutting method was more suitable. Floating was a better seed sorting technique than weighing for separating full from incompletely filled seeds. Seed viability in seed collections that had been sorted to contain only fully developed seeds was assessed using tetrazolium salts. Viability was generally high (mostly >80%), suggesting that poor germination in studies with well-sorted seeds is likely to be due to seed dormancy.