LIFE-HISTORY VARIATION IN BLUE FLAX (LINUM PERENNE, LINACEAE) - SEED-GERMINATION PHENOLOGY

Linum perenne L. is a nonclonal perennial herb widely distributed acro ss a range of habitats. Variation in seed germination patterns was exa mined for 21 Intermountain collections and for the commercial cultivar 'Appar'. Collections from sites with long, snowy winters were largely dormant at harvest and responded positively to chilling. Collections from middle elevation sagebrush-grassland sites were generally nondorm ant and contained a fraction induced into secondary dormancy by chilli ng. Collections from palouse prairie and pinyon-juniper sites were gen erally nondormant and unaffected by chilling, as was 'Appar'. When see ds of contrasting populations were planted in seed retrieval experimen ts at low, middle, and high elevation sites, their Geld germination ph enology was predictable from laboratory experiments. In common garden experiments, there were significant among-sibship differences in germi nation for each garden-grown wild accession but not for 'Appar', sugge sting that differences both among and within populations may be geneti cally based. Garden-grown seeds were generally less dormant than wild- collected seeds, possibly because of selection during propagation. Res ults demonstrated the existence of ecologically relevant among-populat ion and within-population variation in germination phenology for blue flax. Seeds of high-montane populations are spring-emerging and have l ittle provision for between-year carryover. Populations from lower ele vation habitats with less predictable weather have seeds with contrast ing germination patterns, allowing for emergence in both fall and spri ng as well as for seed bank carryover. 'Appar' seeds lack these predic tive and carryover mechanisms.