Distribution of corticolous noncrustose lichens on trunks of Rocky Mountain junipers in Boulder County, Colorado.

Nineteen species of noncrustose lichens were found on Juniperus scopulorum bark; 3 species had relatively high cover and frequency values and were characterized as typical lichens of Rocky Mountain junipers: Xanthoria fallax, Phaeophyscia hirsuta and Physcia caesia. Total cover per tree was low (4%) and most species preferred the N and E sides of trunk bases. These distributional trends may reflect gradients of exposure to wind, insolation, and rate of bark exfoliation. -Author Juniperus scopulorum Phaeophyscia hirsuta Physcia caesia Xanthoria fallax.