California’s Sierra Nevada mountains are dotted with populations of checkerspot butterflies that belong to the same species but lead separate lives. The populations are differentiated by the host plants where females lay their eggs, with one type favoring Collinsis torreyi (blue-eyed Mary) and the other favoring Pedicularis semibarbata (pine lousewort). Other than that, the checkerspots are muc...

Presented here are new combinations made in advance of publication an Annotated Checklist for the Flora Nevada. New Aliciella latifolia var. imperialis, Androsace elongata acuta, Arceuthobium abietinum grandae, magnificae, mathiasenii, wiensii, Artemisia cana bolanderi, Askellia pygmaea ramosa, Boechera fernaldiana vivariensis, Calystegia sepium limnophila, Camissoniopsis pallida hallii, Cassio...

Rocky Mountain bristlecone pine (Pinus aristata) and limber pine (Pinus flexilis) are important highelevation pines of the southern Rockies that are forecast to decline due to the recent spread of white pine blister rust (Cronartium ribicola) into this region. Proactive management strategies to promote the evolution of rust resistance and maintain ecosystem function require an improved understa...