• Phenology and Stand Composition of Woody Riparian Plants in the Southwestern United States

      Brock, John H.; School of Agribusiness and Environmental Resources, Arizona State University (University of Arizona (Tucson, AZ), 1994-06)
      Knowledge of phenology is important for understanding the autecology of a species. Information concerning flowering dates, leaf development, seed/fruit dispersal, and aberrant weather effects on phenological status of a species should be well utilized by persons interested in the ecology, management and restoration of riparian communities. The phenology and stand composition of key woody species from selected riparian areas of the southwestern United States was studied. Eight riparian tree species were observed monthly (bimonthly in summer) at six sites in eastern Arizona and New Mexico. Phenological events were placed into eight categories for data collection. Stand composition data was collected from four randomly located macroplots at each site in the summer of 1983. Weather data for the period of study was summarized for the region. Four general phenology groups were identified: 1) spring flowering and fruit dispersal as characterized by Fremont cottonwood (Populus fremontii) and Goodding willow (Salix gooddingii), 2) Spring flowering/autumn-winter fruit dispersal characterized by box elder (Acer negundo var. interius), netleaf hackberry (Celtis reticulata), Arizona sycamore (Plantanus wrightii), and velvet ash (Fraxinuspennsylvanica ssp. velutina), 3) Spring flowering and late summer fruit dispersal demonstrated by Arizona walnut (Juglans major), and 4) Multidate flowering and fruit dispersal displayed by velvet mesquite (Prosopis velutina). Fremont cottonwood and Goodding willow dominated the sites, while netleaf hackberry, box elder, velvet ash and Arizona walnut were minor components of the stands. Variation in phenology of the tree species reflected individual species adaptations to the particular environment.