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taxa subjected to four treatments: fresh (F), dried then frozen (D), cold stratified (C), warm <br /> then cold (WC). They found the following for H. congesta: seeds germinated gradually, <br /> mean time to germinate (time in days from when seeds were moistened to when half of the <br /> maximum number of seeds to germinate had germinated) = 80.4 days for D treatment; <br /> maximum mean proportion of germinated seeds (mean ± SD) = 0.230 ± 0.175 for D <br /> treatment; no seeds germinated for WC treatment. Seed bank persistence is not known. <br /> Phenology: Under some conditions, leaf rosettes can be green all year, even in the winter. <br /> Flowering shoots emerge in mid - spring, with flowering occurring from mid -June to early <br /> July. Fruits mature in mid -late summer. <br /> Reproductive Biology and Breeding System: Breeding system is not known; plants appear <br /> to reproduce by seed, produce one or more flowering stems and probably require insects for <br /> pollination (Kaye and Gisler 1993). Vegetative reproduction does not occur except when the <br /> center of a plant crow dies and the surviving crowns around the edge of the plant gradually <br /> grow apart. <br /> Pollinators: Field observations suggest that insects, such as solitary bees and syrphid flies, <br /> are responsible for cross - pollination (Kaye and Gisler 1993). <br /> Seed/Fruit Dispersal and Establishment Mechanisms: Seed dispersal mechanisms are not <br /> known, but there appear to be no special dispersal mechanisms. At Willow Creek, seedling <br /> establishment appears to be more frequent in the year following a prescribed burn, which <br /> removes the vegetative litter and increased the availability of bare microsites for seedling <br /> establishment. <br /> Potential habitat modifications: Woody plant invasion seems to decrease the suitability of <br /> habitat for this species. Prescribed burns and manual tree removal have been done in H. <br /> congesta habitat at Willow Creek, and populations have increased greatly in some of the <br /> areas where this work has been done. In a monitoring area that was cleared in 1992 and <br /> burned in 1991 and 1994, the population has increased by 30%, from 396 plants in 1993 to <br /> 516 plants in 1995. <br /> Herbivory, Seed Predation and Disease: Not known <br /> Impacts of Exotic Plants: Like the other rare native prairie species, competition with <br /> invasive non - native plant species is a threat at many sites. Agrostis tenuis, Anthoxanthum <br /> odoratum, Festuca arundinacea, Phalaris arundinacea, Chrysanthemum leucanthemum, <br /> Daucus carota, Hypochaeris radicata, and Plantago lanceolata are among the invasive non- <br /> native plant species that commonly occur in the native prairie habitat of H. congesta. <br /> 4) Scientific Name: Lomatium bradshawii (Rose) Mathias & Constance <br /> 9 <br />