The pollination ecology and reproductive biology of Gentiana newberryi (Gentianaceae) in the eastern Sierra Nevada

Gentiana newberryi Gray flowers at Little Valley (2000 m) and Forestdale Divide (2580 m) were significantly larger and produced more ovules than flowers at Frog Lakes (3120 m). Predation significantly reduced seed set at the higher elevation sites. Herbivores removed 37.9% of the flowers at Frog Lakes and predispersal seed predators consumed all of the seeds in 64.3% of seed capsules at Forestdale Divide and 3.0% at Frog Lakes.; There was a significant relationship between the number of bees present and the number of seeds produced at Little Valley. Self fertilized seeds (autogamy) germinated at the same rate as cross pollinated seeds (allogamy). The number of seeds produced by self pollination is probably limited anatomically since flowers that were hand pollinated with pollen from a flower on the same plant (geitonogamy) did not produce significantly fewer seeds than cross pollinated flowers.