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A Flora Of The Higher Ranges And The Kelso Dunes Of The Eastern Mojave Desert In California, Robert P. Thorne, Barry A. Prigge, James Henrickson

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Simulating The Water Requirements And Economic Feasibility Of Corn In The Midwest, Wendi L. Palmer, B. J. Barfield, M. E. Bitzer, C. T. Haan

KWRRI Research Reports

An evaluation of the economics of supplemental irrigation when using a surface water supply must be site specific in order to account for variations in soil moisture holding capacity, watershed area supplying the runoff, climatic conditions, and proposed irrigation management procedures.

With the use of farm specific simulation models to determine grain yields, availability of irrigation water, and economic expenditures involved in irrigation, an economic evaluation of supplemental irrigation can be performed, In the model presented in this report, the Duncan SIMAIZ model is used to predict grain yields using long-term daily weather information. SIMAIZ also determines irrigation water demand …

Soil Chemistry Relationships Of The Tecate Cypress In The Santa Ana Mountains, California, David E. Sottlemeyer, Earl W. Lathrop

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.

Physiological Research On Adventitious Shoot Development In Aspen, George A. Schier

Aspen Bibliography

No abstract provided.

Ecology And Regeneration Of Aspen In Relation To Managment, R.K. Tew

Aspen Bibliography

No abstract provided.

Tree Biomass Estimates For Minnesota's Aspen-Birch Forest Survey Unit, Gerhard K. Raile, Pamela J. Jakes

Aspen Bibliography

No abstract provided.

Effects Of Reduced Tillage And Multiple Cropping On Plant Diseases, Donald R. Sumner, Ben Doupnik Jr., M. G. Boosalis

Department of Plant Pathology: Faculty Publications

In the past, tillage research on plant diseases was concerned primarily with practices that buried plant residues in single-crop production systems. The burial of plant debris to destroy pathogens is an ancient agricultural prac­ tice (34). Each crop was tested as a single entity, and most crop rotations were based on one crop per year. Interest in notill and conservation tillage systems and mUltiple cropping has increased in the past two decades be­ cause of the scarcity and increased cost of fossil fuels, periodic world food shortages, and the concern over soil erosion (73,110). These concerns are of such paramount …

Minnesota's Aspen Resource, Pamela J. Jakes

Aspen Bibliography

No abstract provided.

Proceedings Of The 8th Annual Meeting, Southern Soybean Disease Workers (March 11-12, 1981, Memphis, Tennessee): Soybeans, The Crop Of The Future

Southern Soybean Disease Workers: Conference Proceedings

General Session

Presidential Address - Glen Whitney

The Influence of Plant Diseases on American Agriculture - Wiley Garrett

Integrated Pest Management: A National Prospective - B. Blair

Development in Brazil, the Future World Supplier of Food: Industry Overview - Ray Smith

Soybean Disease Loss Estimate - R. V. Sturgeon

Soybeans, Seed, Seedling, and Soil-Borne Disease, James Kantzes presiding

Standardized Seed Treatment Research Report - M. C. McDaniel

Soybean Seedling Disease Control and Plant Populations - Norman Horn

Metalaxyl: A New Seed Dressing and Soil Treatment Fungicide - H. V. Morton and D. Houseworth

Soybean Seed Treatment: U. S. Status …

Field Maps 1981, Grace K. Attea, Ryan W. Mcewan, John L. Vankat

Data Files for Old-Growth Deciduous Forest Dynamics Archive: Hueston Woods

Historical field map scans (1981) for the permanent 100m x 105m research plot in Hueston Woods State Nature Preserve.

Maps were digitized in 2022.

Classification And Protection Status Of Remnant Natural Plant Communities In Arkansas, William F. Pell

Journal of the Arkansas Academy of Science

A classification and inventory of Arkansas's remaining tracts of relatively undisturbed vegetation was initiated in 1979. Based on extensive literature surveys and field work, the classification includes five physiognomic classes, 17 cover classes, and 46 cover types, arranged hierarchically. High quality examples of ten of the cover types have been located in designated wilderness or state natural areas, where they are protected by law, while an additional three occur in research natural areas or Forest Service special interest areas. The remaining 33 cover types have no known long-term protection. Lands having wilderness, state natural area, research natural area, or special …

Lichens Of Arkansas Ii. Additional State Records Through Computer Search, Jewel E. Moore

Journal of the Arkansas Academy of Science

No abstract provided.

Insecticides And Pheromones Used In The Midwest. A Short Review, Evelyn Osbourne, Paul Schwartz

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

The Midwest produces most of the food and feed grains and oilseeds grown in the US. as well as a substantial proportion of a variety of other crops, but corn accounts for at least 75% of insecticide use in the region. The total amount of insecticides used on crops could be greatly reduced if economic losses from insects could be predicted accurately. We will examine the current status of chemical controls for insects of economic importance to this region, indicating some areas where new developments are needed or are likely to occur.

Determination Of Selenium In Biological Materials By Stable Isotope Dilution Gas Chromatography-Mass Spectrometry, Donald C. Reamer, Claude Veillon

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Selenium can be determined quantitatively in biological samples after digestion using nitric acid, orthophosphoric acid, and hydrogen peroxide and the formation of 5-nitropiazselenol. Samples are spiked with enriched ⁸²Se and lsotoplc ratio of ⁸⁰Se to ⁸²Se is measured by combined gas chromatographymass spectrometry using dual ion monitoring. Precise determination at the parts-per-billion level is possible. The accuracy of the method Is verlfied by using standard reference materials.

Housing And Management To Reduce Climactic Impacts On Livestock, G. Leroy Hahn

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Weather is a constraint on efficient livestock production systems. Evaluation of the degree of constraint is a difficult, but necessary task before selection of appropriate modifications in management or environments can be made. The basis for rational selection from available alternatives for the limitation of climatic stress in livestock has continued to improve, particularly with the development of rudimentary functional relationships between animal performance and weather parameters. Such relationships, when combined with probabilistic knowledge of the weather parameters, permit prediction of the reduction in animal performance under natural conditions, or of the benefits to be derived from proposed housing or …

Grain Legume Agronomy Programme, G Walton

Experimental Summaries - Plant Research

Lupin agronomy, series 1 - growth factor interactions. To evaluate the relative influence that various growth factors exert on crop yield. Lupin agronomy, series 2 - harvest index response to density. To establish whether the harvest index of the plants at maximum crop yield density remains constant over a range of environmental conditions and whether differences exist between cultivars. Lupin agronomy - nutrition. To compare the grain yield response to potash rates. Grain legumes for wheatbelt rotations. To compare the soil fertility after one year growth of different legume species. In the 1981 experiments, Derrimut field pea yielded well, outyielding …

Comparative Water Relations And Photosynthesis Of Mycorrhizal And Non-Mycorrhizal Bouteloua Gracilis H.B.K. Lag Ex Steud., Michael F. Allen, William K. Smith, Thomas S. Moore Jr., Martha Christensen

Department of Plant Pathology: Faculty Publications

The rangeland grass, Bouteloua gracilis was inoculated with its mycorrhizal symbiont, Glomus fasciculatus, to determine the influence of vesicular-arhuscular mycorrhizae on water status, stomatal behaviour and photosynthesis as well as gross plant morphology, biomass and phosphorus content. Mycorrhizal infection increased transpiration rates by over 100% with 50 to 70% lower leaf resistances to water vapour diffusion. Leaf xylem pressure was not different between mycorrhizal and non-mycorrhizal plants indicating that whole-plant resistance to water transport was reduced by more than 50%. Photosynthetic rates under saturating light conditions increased 68% with infection as a consequence of a 33% reduction in stomatal …

Cover Of Plants With Extrafloral Nectaries At Four Northern California Sites, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Percent cover of plants with extrafloral nectaries was investigated in three California habitats with the same physiognomy as habitats previously studied in Nebraska (perennial native grassland, riparian forest, deciduous forest). In contrast to Nebraska where cover of plants with extrafloral nectaries reached 14 percent, no plants with extrafloral nectaries were found in any California transect. Chaparral was also studied; no plants with extrafloral nectaries were found.

Blood Flow To The Corpus Luteum-Bearing Ovary And Ipsilateral Uterine Horn Of Cows During The Oestrous Cycle And Early Pregnancy, S. P. Ford, J. R. Chenault

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

Total ovarian blood flow of cows (sum of flows through the ovarian artery and uterine branch of the ovarian artery), measured by electromagnetic flow probes, followed a consistent cyclic pattern, being highest from Day 10 of the oestrous cycle (oestrus = Day 0) until 4 days before the subsequent oestrus. During this period of high ovarian blood flow, blood of uterine origin flowed to the ovary through the uterine branch of the ovarian artery and was found to comprise 20-40% of the ovarian blood flow. Between Days -4 and -3, ovarian blood flow dropped (P < 0·01)from 3·2 ± 0·5 to 1·0 ± 0·4 ml/min, coincident with a reversal of flow through this anastomosis. Uterine arterial blood flow was highest (P < 0·05)from 1 day before oestrus to the day of oestrus when compared to the remaining days of the oestrous cycle. Throughout the oestrous cycle, ovarian blood flow was positively correlated with systemic concentrations of progesterone (r = 0·55, P < 0·01)and negatively correlated with systemic concentrations of oestradiol-17β (r = -0·42, P < 0·01). In contrast, uterine arterial blood flow was negatively correlated with systemic progesterone (r =-0·25, P < 0·05) and positively correlated with systemic oestradiol (r = 0·45, P < 0·05). These data provide direct evidence in the cow that a portion of the blood flowing to the ovary containing a fully functional corpus luteum is contributed by the ipsilateral uterine artery.

Moss Sensitivity To Sulfur Dioxide, John W. Wilcut

Masters Theses

Extensive research regarding the effects of sulfur dioxide (SO₂) on vascular and nonvascular plants has been reported. Sulfur dioxide has been shown to interrupt normal metabolism, to interrupt normal reproduction, and to alter the plant's morphology.

One hypothesis regarding the lack of bryophytes in urban areas is that the life cycle is being interrupted. It has been shown that moss protonemata are sensitive to SO₂ concentrations in urban areas. Several authors noted that sexual reproduction is blocked among many species which do occur in urban environments. Observations on protonemal sensitivity are probably more important than the observations …

The Terrestrial Flora Of South Padre Island, Texas, Robert I. Lonard, Frank W. Judd

School of Integrative Biological & Chemical Sciences (Formerly Dept. of Biology)

The primary aim of this work is to enable the user to identify the flowering plants of South Padre Island; however, it should be useful for identification of plants on other Texas barrier islands and on the Mexican barrier islands. We hope that the keys will aid teachers, students, coastal zone managers, and individuals conducting environmental impact assessments.

Variation In Branch Growth Characteristics Of Pinus Contorta Infected With Arceuthobium Americanum, Lynn Anne Larsen

Dissertations and Theses

Arceuthobium americanum is a flowering plant which parasitizes Pinus contorta (Lodgepole pine). This study examined branch performance of P. contorta infected to varying degrees with A. americanum.

Ratoon Stunting Disease Of Sugarcane: Isolation Of The Causal Bacterium, Michael J. Davis, A. Graves Gillaspie, Russell W. Harris, Roger H. Lawson

United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications

A small coryneform bacterium was consistently isolated from sugarcane with ratoon stunting disease and shown to be the causal agent. A similar bacterium was isolated from Bermuda grass. Both strains multiplied in sugarcane and Bermuda grass, but the Bermuda grass strain did not incite the symptoms of ratoon stunting disease in sugarcane. Shoot growth in Bermuda grass was retarded by both strains.

An Analysis Of Cadmium And Lead Uptake In Hydroponically Grown Corn Seedlings, Julie Jones Medlin

Dissertations

The purpose of this study was to analyze selected growth parameters of hydroponically grown corn seedlings (Zea mays) in relation to the uptake of the heavy metals, lead and cadmium. The corn seedlings were treated with various concentrations of lead and cadmium at different levels of pH, and phosphate and ferric ion concentrations. Root and shoot lengths were measured before and after heavy metal treatment to determine the relative growth in the different treatment solutions. Wet and dry weights were also obtained. The plant material was digested with nitric and perchloric acids in preparation for analysis for heavy metal content …

Effect Of Nitrogen Levels On Metribuzin Tolerance In Tomatoes, Esther H. Nelson, Richard A. Ashley

Storrs Agricultural Experiment Station

No abstract provided.

Mineral Compostition Of Atriplex Hymenelytra Growing In The Northern Mojave Desert, A. Wallace, E. M. Romney, R. B. Hunter, J. E. Kinnear, G. V. Alexander

Great Basin Naturalist Memoirs

Fifty samples of Atriplex hymenelytra (Torr.) S. Wats, were collected from several different locations in southern Nevada and California to test variability in mineral composition. Only Na, V, P. Ca, Mg, Mn, and Sr in the samples appeared to represent a uniform population resulting in normal curves for frequency distribution. Even so, about 40 percent of the variance for these elements was due to location. All elements differed enough with location so that no element really represented a uniform population. The coefficient of variation for most elements was over 40 percent and one was over 100 percent. The proportion of …

Parent Material Which Produces Saline Outcrops As A Factor In Differential Distribution Of Perennial Plants In The Northern Mojave Desert, A. Wallace, E. M. Romney, R. A. Wood, A. A. El-Ghonemy, S. A. Bamberg

Great Basin Naturalist Memoirs

An area of 0.46 km² divided into six zones in the northern Mojave Desert transitional with the Great Basin Desert has been studied. Diversity is high among the perennial plant species within the 0.46 km² area. Common species for the two deserts that are present in the area studied are Atriplex confertifolia (Torr. & Frem.) S.Wats., Ceratoides lanata (Pursh) J. T. Howell, Grayia spinosa (Hook.) Moq., Ephedra nevadensis S. Wats. Some other species present include Lycium andersonii A. Gray, Lycium pallidum Miers, Ambrosia dumosa (A. Gray) Payne., Larrea tridentata (Sesse & Moc. ex DC) Cov., Acamptopappus shockleyi A. …

The Prairie Naturalist Volume 12, Numbers 3 And 4. September–December 1980

The Prairie Naturalist

THE FLORA AND SANDHILLS PRAIRIE COMMUNITIES OF ARAPAHO PRAIRIE, ARTHUR COUNTY, NEBRASKA ▪ K. H. Keeler, A. T. Harrison and L. S. Vescio

USE OF ULTRASONIC SOUND TO ESTIMATE BODY FAT DEPOTS IN THE MALLARD ▪ G. A. Baldassarre, R. J. Whyte and E. G. Bolen

NORTHERN MOCKINGBIRD BREEDING IN NORTH DAKOTA ▪ D. Child, J. Fontaine, T. Gatz, M. Johnson and J. Oswald

SPRING ARRIVAL OF BIRDS AT WOODWORTH, NORTH DAKOTA ▪ K. F. Higgins, L. M. Kirsch, and J. M. Callow

HYBRIDIZATION AND TAXONOMIC STATUS OF GREATER PRAIRIE CHICKENS AND SHARP-TAILED GROUSE (HYBRIDIZATION IN GROUSE) ▪ D. W. …

Transpiration And Co2 Fixation Of Selected Desert Shrubs As Related To Soil-Water Potential, S. B. Clark, J. Letey Jr., O. R. Lunt, A. Wallace, G. E. Kleinkopf, E. M. Romney

Great Basin Naturalist Memoirs

In desert plants, transpiration rates decreased before photosynthetic rates when plants were entering a period of water stress. This may have adaptive consequences. A difference of -5 bars in the soil-moisture potential had considerable importance in reducing the rate of transpiration. In Helianthus annuus L. (sunflower) the photosynthetic rate decreased before the transpiration rate in contrast to Great Basin-Mojave Desert plants, and the changes occurred with a -1 bar difference in soil-moisture potential. Morphological changes in three desert plant species [Artemisia tridentata Nutt., Ambrosia dumosa (Gray) Payne, Larrea tridentata (Ses. Moc. ex DC) Cov.] as the soil-moisture potential decreased …

Litter Production And Nutrient Content Of Litter In The Seasonally Flooded Dismal Swamp, Marta M. Gomez

Biological Sciences Theses & Dissertations

Litter production was studied in four plant communities in the Great Dismal Swamp, Virginia, that differ primarily in species composition and flooding regime. Greatest leaf deposition occurred in the more flooded communities, maple-gum (Acer-Nyssa) with 536 g m^-2 yr^-1 and cypress (Taxodium distichum (L.) Richard) with 528 g m^-2 yr^-1, followed by the cedar (Chamaecyparis thyoides (L.) BSP) and mixed hardwood (Quercus-Acer-Nyssa-Liquidambar) communities with 506 g m^-2 yr^-1 and 455 g m^-2 yr^-1, respectively. Litter nutrient concentrations were generally higher in the cypress and maple-gum stands, indicating greater nutrient availability …