• Famine Foods of Rajasthan Desert

      Bhansali, R. Raj; Central Arid Zone Research Institute (University of Arizona (Tucson, AZ), 2011-12)
    • Famous Arizona Botanists

      Miller, Victor (University of Arizona (Tucson, AZ), 1999-06)
    • Ferns and Fern Allies of the Garden Canyon Area of the Huachuca Mountains, Cochise County, Arizona

      Yatskievych, George; Department of Plant Sciences, University of Arizona (University of Arizona (Tucson, AZ), 1981)
    • Field Evaluations of Agave in Arizona

      McDaniel, Robert G.; Department of Plant Sciences, University of Arizona (University of Arizona (Tucson, AZ), 1985)
      Four agave species (Agave americana L., A. murpheyi E Gibson, A. palmeri Engelm., and A. parryi Engelm.) have been evaluated in a four-year study conducted at four Arizona field locations. Survival data, growth rates, approximate water requirements, and insect predation have been analyzed under Arizona field conditions. All species showed good survival at the Marana location, with Agave americana exhibiting the most rapid growth increment, averaging fresh weight gains of 70 to 110 kg per plant in the four-year period, with minimal supplemental irrigation. Analysis of carbohydrates in these plants showed an average 50% sugars on a dry weight basis. Projected growth parameters and biomass accumulation data are presented.
    • Flora of the Pinaleno Mountains, Graham County, Arizona

      Johnson, William Theodore; Arizona State University (University of Arizona (Tucson, AZ), 1988)
      The Pinaleno Mountains lie between the San Simon and Sulphur Springs Valleys in southeastern Arizona. The Pinalenos are one of three mountain ranges in Graham County managed by the Coronado National Forest. Forest Service management of this range is currently at a crossroads. Either a strict preservation policy will prevail or the development of an astrophysical observatory will be allowed. The most notable features of the Pinalenos, the third highest range in Arizona, are the abundance of perennial streams and the significant elevational range of 2050 m (6,720 ft.) on the northeast slope. Recognized in the study area of this northwest-southeast oriented range are six habitats: Aquatic/Semi-aquatic, Isolated Rock Outcrops, Mixed Conifer Forest, Mountain Meadows, Ponderosa Pine Forest, and Woodland. Documented vascular plant resources consist of 449 taxa including 4 taxa of subspecific rank and 438 species in 306 genera and 95 families.
    • Flora of the South Mountains of South-central Arizona

      Daniel, Thomas F.; Butterwick, Mary L.; California Academy of Sciences (University of Arizona (Tucson, AZ), 1992)
    • Floral Biology of Jojoba (Simmondsia chinensis), an Anemophilous Plant

      Buchmann, Stephen L.; USDA Agricultural Research Service; Department of Ecology and Evolutionary Biology, University of Arizona (University of Arizona (Tucson, AZ), 1987)
      Simmondsia chinensis is a widespread perennial plant native to the Sonoran Desert of the United States and northern Mexico. Individuals are dioecious with small unisexual flowers borne on separate plants. The plants are strictly wind-pollinated (anemophilous). Honey bees (Apis mellifera) and native bees often collect large amounts of pollen from male plants but are never found visiting female plants, as there are no floral attractants or rewards in the form of volatiles or nectar, in the green apetalous female flowers. Male plants produce copious amounts of pollen, up to an estimated 523 g/plant, [0.5-2.4 mg/flower, or 8.3-48.9 mg/inflorescence]. Per anther there are from 11,000 to 18,000 pollen grains. The pollen is small, smooth with little exine sculpturing and averages 34μ in equatorial diameter. There is almost no surface oily pollenkitt on the grains. Anthers dehisce and pollen is shed during the entire day, but with an early afternoon peak from 1300 to 1500 MST. This corresponds to peak atmospheric concentrations of 60-63 grains/cubic meter during this period. Seasonal data for Jojoba aerial pollen concentrations and selected hourly values for certain days are also presented for 1982 and 1983 in a native stand. Data on floral number, floral ontogeny, stigmatic receptivity, and seeds per fruit, are also presented for Jojoba.
    • Floral Survey of Central and Northern Namibia

      Butler, Gregory J.; Liang, Irene; Sussman, Spencer; Wilson, Tom; The University of Arizona, School of Natural Resource and the Environment; The University of Arizona, Department of Soil, Water, and Environmental Sciences (University of Arizona (Tucson, AZ), 2010-12)
      The Boyce Thompson Arboretum, an Arizona State Park located in Superior, Arizona, selected a three member team of researchers to study unique plants found in central and northern Namibia. The results of this study will be used to select plants for cultivation in a new southern African flora exhibit at Boyce Thompson Arboretum representing the floral diversity of the Kalahari, Karoo and Namib deserts. This botanic survey was conducted during a University of Arizona study abroad class which took place May 24-July 4, 2010. As part of the survey, the related soil, ecologic, climatic, geographical, and ethnobotanic characteristics were recorded. Size, distribution, and location for each species were noted and land formations were documented. The land formations and soils of Namibia were superficially similar to those of southeastern Arizona. To contribute to Boyce Thompson Arboretum's educational public outreach objectives, we recorded the varied uses of plants based on personal observations, data found in published materials, and interviews conducted with the Himba people. Based on our results, we recommended 21 species suitable for cultivation and interpretation in the new exhibit.
    • Flowering Phenology and Outcrossing in Tetraploid Grindelia camporum Green

      Schuck, Susan M.; McLaughlin, Steven P.; University of Arizona (University of Arizona (Tucson, AZ), 1988)
      Several reproductive processes of tetraploid Grindelia camporum were investigated. This plant is a potential resin crop for the southwestern United States. Field observations of 100 flower heads from unopened buds through 100% achene dispersal were made. It was found that individual flower heads are available for pollination for approximately 5 days but all disc florets are open for only 1 day. On average, achenes mature in 22 days and are dispersed 53 days after flowering. Fourteen-hundred hand-pollinations were also made on plants from 6 wild populations of G. camporum grown in a greenhouse and shade house. Estimates of fertility and crossability of populations were made based on achene number and achene weight data from these crosses. All populations studied were interfertile and no evidence of outbreeding depression in between -population crosses was found. It is shown that tetraploid G. camporum is self-incompatible and requires manipulation for achene set.
    • Forest Litter as a Seed Source in Coal Mine Reclamation in the Southwest

      Day, A. D.; Ludeke, K. L.; University of Arizona; Ludeke Corporation (University of Arizona (Tucson, AZ), 1990)
      Forest litter, a good source of organic matter and seeds, was applied on undisturbed soil and on coal mine soil (spoils) in experiments conducted on the Black Mesa Coal Mine near Kayenta, Arizona over a 2 -year period (1977 - 1978). Germination, seedling establishment, plant height, and ground cover were evaluated for two seeding treatments (forest litter and no forest litter) and two soil- moisture treatments (natural rainfall and natural rainfall plus irrigation). The forest litter was obtained at random from the Coconino National Forest, broadcast over the surface of the soil materials, and incorporated into the surface 5 cm of each soil material. Germination, seedling establishment, plant height, and ground cover on undisturbed soil and coal mine soil were higher when forest litter was applied than when it was not applied and when natural rainfall was supplemented with sprinkler irrigation than when rainfall was not supplemented with irrigation. Applications of forest litter and supplemental irrigation may insure successful establishment of vegetation on areas disturbed by open -pit coal mining.
    • Foreward

      University of Arizona (Tucson, AZ), 1982
    • 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.
    • Freshwater Islands in a Desert Sand Sea: The Hydrology, Flora, and Phytogeography of the Gran Desierto Oases of Northwestern Mexico

      Ezcurra, Exequiel; Felger, Richard S.; Russell, Ann D.; Equihua, Miguel; Universidad Nacional Autónoma de México; University of Arizona; University of Washington; Instituto de Ecología (University of Arizona (Tucson, AZ), 1988)
      The Adair Bay pozos (water holes) are small artesian springs scattered along the saltflats of the Gran Desierto near the coast of the Gulf of California in northwestern Sonora. The pozos provide essential fresh water for the rich bird fauna and some of the mammals, and were also utilized earlier by native people. The Gran Desierto aquifer appears to consist of sand and gravel deposited in ancient river beds which were subsequently overlain by dunes. Toward the coast, the alluvial aquifer becomes confined, or buried, beneath the relatively impermeable clays of the saltflats. These clays act as a barrier which causes artesian pressure to develop within the underlying aquifer. Pozos appear to develop at locations in which the permeability of the clay is increased, possibly by desiccation cracking or by flocculation due to ion exchange. The hypothesized existence of a buried fluvial system may explain the occurrence of clusters of pozos in some saltflats and their absence in many others, i.e., pozos only occur in saltflats with an underlying waterway. Alkali Weed (Nitrophila occidentalis) is the first plant to colonize places where the aquifer has broken through the overlying clays and reaches the surface or near the surface. This plant is a good indicator of fresh water. Coyotes seek fresh water in these places. Such action of coyotes and perhaps other animals seems to be related to the formation of smaller pozos. Saltgrass (Distichlis spicata) is the second plant to colonize a pozo and larger oases are colonized by a more diverse flora. The flora of the pozos is markedly different from that of the rest of the Sonoran Desert, both in life -form spectrum and geographic origin. The pozos support 26 species of vascular plants, many of which show temperate affinities. Several members of this flora are new geographic records: Indian Hemp (Apocynum cannabinum in the Apocynaceae), new for Sonora and the Sonoran Desert; Lythrum californicum in the Lythraceae, new for Sonora; Greasewood (Sarcobatus vermiculatus in the Chenopodiaceae), a new generic record for Mexico. The pozos are island -like relicts of the delta of the Colorado River. With the delta ecosystem now virtually destroyed, the local extinction of any wetland species in the pozo flora will most probably not be followed by new immigrants of the same flora, but by introduced weed species such as Salt Cedar (Tamarix ramosissima). The species -area relationship of the pozo flora is similar in value to that for other island ecosystems, although the exponential parameter (z = 0.263) is significantly higher than Preston's "canonical" value and the scale coefficient is significantly higher (k = 0.75) than those for other small island ecosystems. The species richness of a pozo is nearly four times higher than that of dry terrestrial islands of comparable size. Based on a projection of a biogeographical model fitted to the floristic richness of the pozos, we estimate that the original flora of the Colorado River delta supported 200 to 400 species of wetland vascular plants. Most of these populations have met local extinction with the destruction of the delta ecosystem of the Colorado River earlier in this century.
    • 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)