• Sub-surface Watering of Tree Seedlings in Arid Regions Using Discarded Plastic Infusion Sets

      Koarkar, A. S.; Muthana, K. D.; Central Arid Zone Research Institute (University of Arizona (Tucson, AZ), 1984)
      The difficulty of establishing tree plantations in arid regions, particularly on sandy and droughty soils, is a widely faced problem. Insufficient water is freely available in such regions for effective watering of tree plantations with conventional methods. Under such conditions, discarded plastic infusion sets from a hospital were tried for watering and establishing Anjan (Hardwickia binata). This allowed use of a limited quantity of water, in a regulated way as in the drip system, and watering directly in the sub -soil to reduce evaporation loss. Either one litre or half a litre of water was applied per plant this way every alternate day for the whole year, with total consumption of 173 litres and 91 litres of water respectively per plant in the entire year. Growth of these plants was compared with growth of ones subjected to conventional watering with 9 litres applied fortnightly to make 216 litres of water per plant for the period of the experiment. Plant growth even with a half litre treatment on alternate days was far superior to that with conventional watering.
    • Formation and Destruction of a Gila River Mesquite Bosque Community

      Minckley, W. L.; Clark, Thomas O.; Department of Zoology, Arizona State University; Center for Environmental Studies, Arizona State University (University of Arizona (Tucson, AZ), 1984)
      Evidence is presented for repeated formation and destruction of a Mesquite (Prosopis spp.) bosque community on a Gila River terrace, eastern Arizona. Terrace formation was induced by a coarse alluvial cone produced by flooding in an ephemeral tributary, followed by vegetative colonization culminating in Mesquite. Destruction was accomplished by sustained flooding in the mainstream Gila River.
    • Observations on Seeds and Seedlings of Fremont Cottonwood

      Fenner, Pattie; Brady, Ward W.; Patton, David R.; Arizona State University; Rocky Mountain Forest and Range Experiment Station, USDA Forest Service (University of Arizona (Tucson, AZ), 1984)
    • Desert Plants, Volume 6, Number 1 (Summer 1984)

      University of Arizona (Tucson, AZ), 1984
    • Plant Geography of Southwestern Sand Dunes

      Bowers, Janice E. (University of Arizona (Tucson, AZ), 1984)
      Patterns of plant distribution among eight dune fields in the southwestern USA and northwestern Mexico are analyzed and discussed. Each dune flora is characterized by three to five geographic components; the regional flora in which each dune field occurs is the dominant component. Endemic species, that is, species restricted to sand dunes, comprise ten percent or more of five of the eight floras. All possible combinations of the eight dune floras taken two at a time (28 pairs) were analyzed using Sorensen's similarity index. Only seven have a similarity value of 0.200 or greater. The lack of similarity among dune floras is due in part to their distribution among four floristically distinct biogeographic provinces and in part to localized recruitment of species from adjacent, non -dune plant communities. Geographic, edaphic and temporal barriers to dispersal and establishment also promote high dissimilarity among the eight floras. Eighty -three of the 533 species composing the eight dune floras are either endemic to sand dunes or occur at three or more of the dune fields studied. These 83 species fall into two subgroups: a group of 36 species characteristic of southwestern sand dunes east of 113° Longitude, and a group of 57 species characteristic of sand dunes west of 113° Longitude. Ten species are common to both groups. In the Southwest, dune fields are habitat islands, but dune floras do not behave in all respects as predicted by the MacArthur and Wilson theory of island biogeography. Southwestern sand dunes are not now floristic islands, but additional insular characteristics may develop over time.
    • John C. Fremont: Explorer, Plant Collector and Politician

      Crosswhite, Frank S.; Boyce Thompson Southwestern Arboretum (University of Arizona (Tucson, AZ), 1984)
    • Aloe vera, Plant Symbolism and the Threshing Floor

      Crosswhite, Frank S.; Crosswhite, Carol D.; Boyce Thompson Southwestern Arboretum (University of Arizona (Tucson, AZ), 1984)
    • Wild Cochineal of Prickly Pear (Opuntia sp.) as a Dye Source in Arizona

      Crosswhite, C. D. (University of Arizona (Tucson, AZ), 1984)
    • The Significance of Cacti in the Diet of the Javelina (Tayassu tajacu)

      Crosswhite, Carol D.; Boyce Thompson Southwestern Arboretum (University of Arizona (Tucson, AZ), 1984)
    • Editorial - The Goodness of Plants

      University of Arizona (Tucson, AZ), 1984
    • Water Conservation Strategies for the Urban Arid Landscape

      Rodiek, Jon; Texas Tech University (University of Arizona (Tucson, AZ), 1984)
    • Ecology and Evolution of Southwestern Riparian Plant Communities

      Reichenbacher, Frank W.; Arizona Game and Fish Department (University of Arizona (Tucson, AZ), 1984)