Life history biology and soil characteristics of two species of Arctomecon (Papaveraceae)

Two rare plant species of the Mojave Desert were investigated in this study. Life history and reproductive data as well as vegetative associates and soil characteristics for Arctomecon californica Torr. and Frem. and Arctomecon merriamii Cov. were collected. Results for the life history and reproductive data show that the highest mortality in both species occurs at the seedling stage. Loss of potential seed, for both species, was highest at the bud and capsule stage. Arctomecon californica was found to be reproductively self-incompatible, while A. merriamii was able to self-pollinate. Results from the vegetative and soil data show that the vegetation where both species were present was very different from sites where Arctomecon did not occur, and that the vegetative associates were not the same as the surrounding Mojave Desert vegetation. Soil results show differences in many components, most notably sulfur and calcium content. Due to habitat specificity, especially for Arctomecon californica, intact gypsum outcrops must be preserved in order to preserve the species