Filters: Tags: {"scheme":"USGS Publications Warehouse"} (X) > Contacts: V. Thomas Parker (X)
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Ecological factors favoring either postfire resprouting or postfire obligate seeding in plants have received considerable attention recently. Three ecological models have been proposed to explain patterns of these two life history types. In this study, we test these three models using data from California chaparral. We take an innovative approach to testing these models by not testing community or landscape patterns, but instead, investigating vegetation structure characteristic of four pairs of resprouting and (non-resprouting) obligate seeding subspecies of Arctostaphylos (Ericaceae), a dominant and diverse shrub genus in California chaparral. Data were analyzed for percentage bare ground, elevation, annual precipitation,...
There is value in understanding the past and how it has affected the present. Science focuses on empirical findings, and we know that our prior experiences and those of our predecessors play important roles in determining how we interpret the present. We learn from accomplishments and foibles of predecessors and appreciate the real life experiences we have gone through. In our studies of the genus Arctostaphylos Adans. we have been struck by the fascinating stories surrounding taxonomists who have played roles in the development of our current understanding of the group. In addition to providing insights, they sometimes provide humor and lessons on the value of competition versus collaboration. We offer this history...
Changes are made in the nomenclature of species and subspecies in the genus Arctostaphylos(Ericaceae). In this study, the focus is on species found in the coast ranges of California. Changes are made in A. nortensis from the area around the Oregon border with California, in the A. nevadensiscomplex in the North Coast Ranges, in the A. nummularia complex of the north to central coast, in the A. tomentosa complex of the central coast to the Channel Islands, and in the A. hookeri and A. pilosula complex of the central coast. Also discussed are other changes presented elsewhere that will affect the Arctostaphylos treatment in the next edition of the Jepson Manual.
The genus Arctostaphylos consists mostly of chaparral shrubs known by the common name manzanita, and one of the widest ranging of these is A. glandulosa Eastw., distributed from Baja California to Oregon. Particularly in the southern half of its range it exhibits complex patterns of morphological variation that have long presented taxonomic challenges. Phenetic analysis of morphological traits from over 1400 individuals from throughout the range were used to examine intra- and inter-population patterns of variation. Multivariate ordination and hierarchical cluster analysis were used to determine phenetic patterns linked with ecological and geographical distributions. These analyses suggest the hypothesis that this...
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