• Gene Transfer Between Tepary and Common Beans

      Pratt, Richard C.; Department of Horticulture, Purdue University (University of Arizona (Tucson, AZ), 1983)
    • Genotype-Environment Interactions in Two Cultivars of Spring Wheat

      Day, A. D.; Swingle, R. S.; Dewey, W. G.; Department of Plant Sciences, University of Arizona; Department of Animal Sciences, University of Arizona; Department of Plant Sciences, Utah State University (University of Arizona (Tucson, AZ), 1981)
    • The Genus Bursera (Burseraceae) in Sonora, Mexico and Arizona, U.S.A.

      Johnson, Matthew B.; University of Arizona (University of Arizona (Tucson, AZ), 1992)
      Bursera is a conspicuous component of the vegetation of Sonora, Mexico. This paper delineates the species of Bursera in the states of Sonora and Arizona and provides identification and descriptions including information on their distribution, habitat, morphology, phenology, and cultivation. There are 10 species of Bursera in Sonora: B. arborea, B. fagaroides, B. grandifolia, B. hindsiana, B. lancifolia, B. laxiflora, B. microphylla, B. penicillata, B. simaruba and B. stenophylla. Two species, B. fagaroides and B. micro - phylla, extend into Arizona. The ten species in Sonora and Arizona occur in desertscrub, thornscrub, tropical deciduous forest and lower oak woodland. Plant stature, leaf size and number of species decrease from southeast to northwest across Sonora. Several species of Bursera are suitable for horticulture. Further study is required to determine the taxonomic relationships of several species.
    • A Genus Treatment for Acacia from Legumes of Arizona: An Illustrated Flora and Reference

      Ebinger, John E.; Seigler, David S. (University of Arizona (Tucson, AZ), 2014)
    • Geomorphology and the Distributional Ecology of Fremont Cottonwood (Populus fremontii) in a Desert Riparian Canyon

      Asplund, Kenneth K.; Gooch, Michael T.; Prescott College (University of Arizona (Tucson, AZ), 1988)
      DBH data were taken from Fremont Cottonwood (Populus fremontii) in a desert riparian canyon in west -central Arizona. Recruitment was found to depend on geomorphologic features and flood "refugia" rather than on the absence of grazing. Populus fremontii is specifically a "strandline," streamside species, particularly of braided aggradations and their associated secondary channels, a microhabitat that ultimately depends on upstream and upslope erosion. The concept of flood -subclimax succession explains virtually nothing of the ecology of obligate riparian trees. Riparian classification based upon geomorphology and hydrology are apt to have significant meaning for biogeography and management.
    • Germination Requirements of Key Southwestern Woody Riparian Species

      Siegel, Richard S.; Brock, John H.; Department of Water Resources, State of Arizona; Arizona State University (University of Arizona (Tucson, AZ), 1990)
      Germination requirements of selected Southwestern woody riparian species were studied in the laboratory. Four common tree species selected for study were Fremont Cottonwood (Populus fremontii), Goodding Willow (Salix gooddingii), Arizona Sycamore (Platanus wrightii) and Velvet Mesquite (Prosopis velutina). Seeds were collected from two major riparian habitats in the southwest. The species tested required a temperature range of 16° C to 27° C for germination. Fremont Cottonwood, Goodding Willow and Velvet Mesquite showed good germination at moisture stress levels of -4 bars or less, whereas Arizona Sycamore only germinated well at 0 bars. For all species tested, germination was better at salinity levels lower than 50 meq /liter NaCl. All species displayed successful germination responses between pH 5 to 7. Velvet Mesquite germinated at all pH levels (5 -10). Longevity of seeds of riparian species is reported to be of short duration. This was confirmed in these studies with southwestern woody riparian species.
    • Great Basin Conifer Woodland

      Brown, David E.; Arizona Game and Fish Department (University of Arizona (Tucson, AZ), 1982)
    • Great Basin Desertscrub

      Turner, Raymond M.; Geological Survey, U.S. Department of the Interior (University of Arizona (Tucson, AZ), 1982)
    • Great Basin Montane Scrubland

      Brown, David E.; Arizona Game and Fish Department (University of Arizona (Tucson, AZ), 1982)
    • Greenhouse Establishment of Alfalfa in Three Soil Materials Associated with Arizona Coal Mining

      Day. A. D.; Department of Plant Sciences, University of Arizona (University of Arizona (Tucson, AZ), 1983)
      The effects of three soil materials, three mulching treatments, and two moisture treatments on the growth and forage production of Vernal' alfalfa (Medicago sativa L.) for use in coal mine waste reclamation were studied in a 3 -year experiment in the greenhouse at Tucson, Arizona. The three soil materials were: (1) Gila loam, (2) Unmined soil, and (3) Coal mine soil. The three mulching treatments were: (1) No mulch, (2) Barley (Hordeum vulgare L.) straw, and (3) Russian thistle (Salsola kali L.). The two soil moisture treatments were: (1) Optimum (60 cm total) and (2) Stressed j30 cm total). Significant differences were observed in number of stems per pot, plant height, and forage yield between soil materials, mulching treatments, and soil moisture treatments. The greatest number of stems per pot, the tallest plants, and the highest forage yield were produced in the Gila loam, barley straw mulch, and optimum soil moisture treatment. Use of a soil mulch (incorporated organic matter mulch) produced better plant growth and more forage than when soils were not mulched. Barley straw was a more effective mulching material than was Russian thistle. Within soil materials and within mulching treatments forage yields were significantly higher with optimum soil moisture than they were when moisture was limited.
    • Growing Teparies in the Desert

      University of Arizona (Tucson, AZ), 1983
    • Guayule, Jojoba, Buffalo Gourd and Russian Thistle: Plant Characteristics, Products and Commercialization Potential

      Foster, Kennith E.; Karpiscak, Martin M.; Taylor, Jonathan G.; Wright, N. Gene; Office of Arid Lands Studies, University of Arizona (University of Arizona (Tucson, AZ), 1983)
    • Habitat Preference of Three Parasitic Orchids Occurring Sympatrically in an Arizona Sky Island

      Verrier, James T.; Univ Arizona, Sch Plant Sci (University of Arizona (Tucson, AZ), 2017-10)
      Detailed habitat information for the holomycotrophic orchids, Corallorhiza maculata, C. striata, and C. wisteriana, was recorded from multiple sites in the Santa Catalina Mountains, southeastern Arizona. This study was initiated to see if there are predictable associations with host trees. Over 1,400 flowering stems were observed from 244 microsites at 10 localities across a 305 m elevational gradient, and within an area of 7 km2 (700 hectares). While C. maculata showed a preference for southwestern white pine (Pinus strobiformis), C. striata associated with white fir (Abies concolor) and bigtooth maple (Acer grandidentatum). White fir and Douglas-fir (Pseudotsuga menzesii var. glauca) were the preferred associates of C. wisteriana. Orchids were found at microsites along lower slopes at up to 45% inclinations and generally 3-24 m above the slope base. Nearly all sites were north facing with moderate to thick leaf litter. A third of all microsites had no forbs or graminoids associated with orchid clusters, confirming the obligate association with primarily conifers. The local distribution showed a pattern of niche partitioning, with the three species occurring in similar habitats but depending on different host trees. Although C. striata and C. wisteriana associated mainly with white fir, C. striata favored habitat with more nutrient-rich soils.
    • Habitat Relationships of Some Native Perennial Grasses in Southeastern Arizona

      Bock, Jane H.; Bock, Carl E.; University of Colorado, Boulder (University of Arizona (Tucson, AZ), 1986)
      Successful management and restoration of any ecosystem requires knowledge of the habitat requirements of its component species, as manifested under natural or near - natural conditions. We measured abundances of common grasses in relation to environmental variables on an undisturbed grassland and oak savannah preserve in southeastern Arizona. Major environmental gradients separating species were 1) slope angle and associated soil differences, 2) distance above wash bottoms or floodplains, and 3) slope compass orientation and amount of oak canopy. Blue Grama (Bouteloua gracilis) was the most widespread and abundant species overall, but it reached highest densities on level lowlands, where it was dominant along with Sacaton (Sporobolus wrightii) and Vine Mesquite (Panicum obtusum). Sideoats Grama (B. curtipendula) was the most abundant species on steep slopes above floodplains and washes, regardless of tree canopy or slope compass orientation. Level to gently rolling uplands were dominated by Blue Grama, Plains Lovegrass (Eragrostis intermedia ), and Wolftail (Lycurus phleoides). Plains Lovegrass in particular seems to be increasing on the study area compared to adjacent grazed sites. Steep and rocky uplands were dominated by Threeawns (Aristida spp.), Curly Mesquite (Hilaria belangeri ), and Sprucetop Grama (B. chondrosioides). These species generally are characteristic of poor sites, and they were more common on grazed lands than on our study area.
    • Herbaceous exotics in Arizona's Riparian Ecosystems

      Stromberg, Juliet C.; Chew, Matthew K.; Center for Environmental Studies, Arizona State University; Arizona State Parks (University of Arizona (Tucson, AZ), 1997-06)
    • High Biodiversity in Association with the Common Baobab Tree

      Hellekson, Lyndsay; The University of Arizona, School of Natural Resources (University of Arizona (Tucson, AZ), 2009-06)
    • Historical Background to Southwestern Ecological Studies

      Brown, David E.; Minckley, W. L.; Collins, James P.; Arizona Game and Fish Department; Department of Zoology, Arizona State University (University of Arizona (Tucson, AZ), 1982)
    • The History and Vegetation of Nombinnie and Round Hill Nature Reserve

      Milthorpe, Peter; NSW Agriculture (University of Arizona (Tucson, AZ), 1998-06)
    • History, Geology and Vegetation of Picketpost Mountain

      Crosswhite, Frank S.; Boyce Thompson Southwestern Arboretum (University of Arizona (Tucson, AZ), 1984)
    • History, Observations and Monitoring of Pediocactus peeblesianus var. fickeiseniae on the Arizona Strip

      Hughes, Lee; The Bureau of Land Management (University of Arizona (Tucson, AZ), 1996-06)