Relationship between form, function, and distribution of two Arctostaphylos species ( Ericaceae) and their putative hybrids.

Plants of Arctostaphylos viscida occur in xeric, low elevation habitats in the Sierra Nevada. A. patula occurs in more mesic, high elevation sites. Where the distribution of these 2 species overlap, putative hybrids are formed. At a site of co-occurrence of these species vegetative characters, reproductive characters, water relations, energy balances, and microhabitat quality were analysed for each of 81 Arctostaphylos plants which were randomly selected across a local environmental gradient. These plants represented not only an apparent genetic cline but also a cline of xerophytism. Plants with mesic charactristics were excluded from xeric habitats but those with xeric features were relatively insensitive to microhabitat aridity.-Authors

Duke Scholars

Author William E. Winner DKU Faculty