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Getting The Lay Of The Land: Introducing North American Native Grasslands, Anthony Joern, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

The expected catastrophic extinction of species (already under way in many places) will alter the planet’s biological diversity so profoundly that, at the known rate of extinction, it will take millions of years to recover. Yet few ecologists study extinction. Indeed, very little ecology deals with any processes that last more than a few years, involve more than a handful of species, and cover an area of more than a few hectares. The temporal, spatial and organizational scales of most ecological studies are such that one can read entire issues of major journals and see no hint of impending catastrophe. …

Introduction From The Changing Prairie: North American Grasslands, Anthony Joern, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Preserving remaining North American grasslands requires a multiability approach. In this book, we investigate three aspects of an admittedly larger problem: (1) how we as humans perceive grasslands; (2) the ecology of grasslands, in order to define the framework within which conservation and preservation efforts must operate; and (3) conservation issues. Additional sociological, economic, philosophical, and cultural considerations will provide important additional insights to preserving and managing grasslands, but are not included here. By restricting our focus to only three issues, we feel that we can provide a basic, but appropriate, understanding of grassland ecosystems for the prairie enthusiast. This …

Population Processes, Kathleen H. Keeler, Anthony Joern

School of Biological Sciences: Faculty Publications

Within the prairies, myriad populations of plants, insects, small mammals, and other organisms form distinct levels of organization. The physical forces of weather and fire and the complex networks of species interactions control each species’s structure and dynamics and determine its abundance or rarity. Variation in population dynamics and interactions over time and space determine the distribution and abundance of species, and ultimately the composition and dynamics of entire prairie communities.

To the casual observer, plant populations on prairies may seem quite static, like museums containing a diverse collection of specimens that can be seen again and again on repeated …

Preface From The Changing Prairie: North American Grasslands, Kathleen H. Keeler, Anthony Joern

School of Biological Sciences: Faculty Publications

North American grasslands have figured prominently in our North American heritage. Prairies first provided significant barriers to westward expansion, and then offered both economic and sociological opportunity, as well as heartache, for settlers. Many artists have gained significant inspiration from the beauty as well as the harshness of this region and its biota. And because of ideal climate and soil conditions, these grasslands have provided the agricultural foundation of which much of the economic growth and stability of the United States has historically depended.

Yet many see North American prairies as beautiful only when manipulated or exploited: Green croplands or …

Adaptation Of Lentil In Western Australia: Germplasm Evaluation In 1994, A. Sarker, K. H.M. Siddique, S P. Loss, Co-Operative Research Centre For Legumes In Mediterranean Agriculture, Department Of Agriculture Western Australia

Grain and other field crops published reports

Lentil is one of the grain legumes with potential for inclusion into Australian farming systems on fine textured, neutral to alkaline soils. It is an important protein source for the large populations of the Indian sub-continent and elsewhere, and the export market potential is excellent. Old Canadian varieties grown on a small scale in Victoria (Laird and Callisto) are poorly adapted to short season WA environments, A number of varieties have recently been selected from ICARDA material and released in Victoria and SA (Digger, Cobber, Matilda and Aldinga), and these have adequate adaptation to commence a lentil industry in WA. …

Grain Legume And Canola Autumn Updates 1995, David Williams

Grain and other field crops published reports

Grain legumes

- Chickpea

- Field pea

- Lentil

- Faba beans

Canola essentials:

Site selection -Paddock selection is critical for a successful canola crop. Avoid paddocks with waterlogging, wind erosion and broadleaf weeds - particularly wild radish, turnip, mustard and doublegees.

Soil type - Canela grows well on most soil types, however it prefers well drained gravel soils, red loams, sandy _loams and deeper duplex soils. Soil pH levels (in CaCl_²) of 4.5 to 8.0 are suitable. Soil test paddock for pH, phosphorus, and potassium levels.

Rotation - Grow canola after manipulated pasture, lupins or other grain …

The Effect Of Nitrogen Fertilization On The Phenology Of Roots In A Barrier Island Sand Dune Community, Everett P. Weber

Biological Sciences Theses & Dissertations

Little work has been done on the phenology of root growth and senescence largely due to methodological difficulties. The application of minirhizotron technology has enabled the tracking of individual roots through an entire growing season. As a result, direct measures of turnover, root growth, and an analysis of cohorts were made. Small plots on a 36 year old dune on Hog Island, a barrier island in the Virginia Coast Reserve Long Term Ecological Research Site, were fertilized with nitrogen. Minirhizotron tubes were installed in each fertilized and control plot. Each tube was sampled monthly for nine months, March through October …

Proposal For Center For Grassland Studies, Ron Case, Dick Clark, Charles A. Francis, Tony Joern, Terry J. Klopfenstein, Lowell E. Moser, Bob Shearman, Ken Vogel, Steven S. Waller

Center for Grassland Studies: Newsletters

Its my pleasure, on behalf of the Grassland Studies Task Force, to forward a proposal for a Center for Grassland Studies for your consideration. The Task Force is extremely pleased with the overwhelming support from a broad base of input. The Task Force has made a major effort through internal and external listening sessions to insure that there was support and in doing so develop a coalition of partners across the University of Nebraska System, state colleges, community colleges, industry, state and federal agencies, public groups, private non-profit organizations and other educational institutions in the region.

Nebraska has a rich …

Bulletin 4283 - Nitrogen Fertilisers For Cereal Production, M. G. Mason

Bulletins 4000 -

Because fertiliser prices are high, it is important to understand what affects the response to fertilisers by crops.

Among the many factors influencing crop response to nitrogen applications, the most important are the season, soil type, paddock history, time of application and source of nitrogen. Before deciding whether to use nitrogen on a cereal crop, which source to use and at what rate, you need some understanding of how these factors work.

Greatest responses to nitrogen fertilisers can be expected in areas with a relatively long growing season. In such areas light soils with a low nitrogen status give the …

Growing Lettuce, Margaret Graham

Horticulture published reports

The commonly cultivated lettuce, Lactuca sativa, is an annual belonging to the sunflower family. It has been cultivated for over 2500 years, and is a popular salad vegetable.

There are three main subspecies commonly grown.

• IL. sativa ssp capitata - Head type - Crisphead is a lettuce with a firm head and brittle leaves. It is the major lettuce type grown in Australia and is also known as iceberg lettuce. - Butterhead (buttercrunch, mignonette) lettuce has soft, pale leaves and a delicate buttery flavour. It is of major importance in Europe, where it is grown as a greenhouse crop.
• L. …

Identification And Characterization Of Aspergillus Nidulans Mutants Defective In Cytokinesis, Steven D. Harris, Jennifer L. Morrell, John E. Hamer

Department of Plant Pathology: Faculty Publications

Filamentous fungi undergo cytokinesis by forming crosswalls termed septa. Here, we describe the genetic and physiological controls governing septation in Aspergillus nidulans. Germinating conidia do not form septa until the completion of their third nuclear division. The first septum is invariantly positioned at the basal end of the germ tube. Block-and-release experiments of nuclear division with benomyl or hydroxyurea, and analysis of various nuclear division mutants demonstrated that septum formation is dependent upon the third mitotic division. Block-and-releasee xperiments with cytochalasin A and the localization of actin in germlings by indirect immunofluorescence showed that actin participated in septum formation. In …

Gascoyne Research Station Field Day, Department Of Agriculture, Western Australia

Horticulture research reports

Gascoyne Research Station Centenary Open Day Thursday 13 October 1994

100 years (1894-1994) Advancing Agriculture

Welcome to the 1994 Field Day at Gascoyne Research Station. At this day you'll have the opportunity to view and hear discussions of some of the latest Research and Development initiatives in horticulture in the region. We will commence activities at the Packing Shed at 3:00 p.m. with introductions and short discussions of new work which is currently in progress. This will be followed by field talks at the trial sites, as listed in this brochure. We are also pleased to include presentations by leaders …

Bryophyte And Pteridophyte Distribution Records Of Southern Arkansas, James R. Bray, Greg A. Whitehead, Daniel L. Marsh, Dennis W. Mcmasters

Journal of the Arkansas Academy of Science

No abstract provided.

Field Maps 1994, Grace K. Attea, Ryan W. Mcewan, John L. Vankat

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

Historical field map scans (1994) for the permanent 100m x 105m research plot in Hueston Woods State Nature Preserve.

Maps were digitized in 2022.

Vegetation Of Maple-Leaved Oak Sites On Sugarloaf And Magazine Mountains, Arkansas, David W. Rouw, George P. Johnson

Journal of the Arkansas Academy of Science

We conducted an analysis of the vegetation of the maple-leaved oak sites on Sugarloaf and Magazine Mountains, Arkansas, during September and October of 1993. The woody vegetation was sampled using the point-quarter method; on Sugarloaf Mountain five transects were sampled (950 m) and on Magazine Mountain four transects were sampled (710 m). Soil samples from each site were collected and analyzed for 15 factors. In total 27 species were recorded and measured for both sites, 18 for Sugarloaf and 19 for Magazine. The Sugarloaf site can be described as a Quercus-Juniperus community and the Magazine site can be described as …

Sex Ratio And Success, An Assessment Of Lindera Melissifolia In Arkansas, Robert D. Wright

Journal of the Arkansas Academy of Science

Lindera melissifolia pondberry, is a federally endangered dioecious shrub found in Arkansas and four other southeastern states. Although by far the greatest area exists in Arkansas, it is broken into numerous small single-sex clones concentrated in two locations. Several stands have been lost during the 1980's according to records of the Arkansas Natural Heritage Commission. Even casual observation reveals that there are more males than females. This suggests dependence on vegetative reproduction, with possible bias against females. This paper reports on work investigating this suggestion. It was found that a 7:1 bias in area covered favors males. Poor survival of …

First Record Of Leptodora Kindti In Dardanelle Reservoir And Status Of Other Recent Additions To Dardanelle Fauna, John D. Rickett, Robert L. Watson

Journal of the Arkansas Academy of Science

No abstract provided.

Purification Of The Major Soybean Leaf Acid Phosphatase That 1s Increased By Seed-Pod Removal, Paul E. Staswick, Chuck Papa, Jing-Feng Huang, Yoon Rhee

Department of Agronomy and Horticulture: Faculty Publications

Fruit removal for 5 weeks after flowering increased acid phosphatase activity 10-fold in soybean (Glycine max 1. Merr. vai Hobbit) leaves compared with normal seed-pod-bearing plants. The major acid phosphatase activity in leaves was purified over 2700-fold, yielding a single polypeptide of 51 kD with a specific activity of 1353 units/mg protein using p-nitrophenylphosphate as the substrate. lsoelectric focusing demonstrated that the purified protein co-migrated with a majority of the activity that increased in leaves following seed-pod removal. lmmunoblot analysis demonstrated that at least part of the increased activity was dueto an increased abundance of the phosphatase protein. In situ …

Fast Tracking Barley Varieties Using Anther Culture, Sue Broughton, Penny Priest

Journal of the Department of Agriculture, Western Australia, Series 4

Breeding new varieties of barley or other cereal crops usually takes between 12 and 15 years. five years of that time may be needed to stabalise the new varieties so that they breed trueto type, but anther culture can reduce this delay to only eight months. This technology will allow the Department of Agriculture's barley breeding programme to respond more rapidly to changes in goals set by industry and to meet market demands.

Cdna Sequence For The Ribulose 1,5 Bisphosphate Carboxylase/Oxygenase Complex Protein A Protein That Accumulates In Soybean Leaves In Response To Fruit Removal, Paul E. Staswick, Steven J. Crafts-Brandner

Department of Agronomy and Horticulture: Faculty Publications

Soybean (Glycine max L.) transiently accumulates two abundant vegetative storage proteins, VSP A and VSP B, in vacuoles of above-ground vegetative tissues (Wittenbach, 1983; Staswick, 1990). As older leaves and stems become a source of exported metabolites for developing sinks, the VSPs are preferentially degraded and the resulting metabolites are presumably mobilized in the xylem and phloem stream. A striking feature of these proteins is that VSP gene expression is dramatically increased in mature leaves following the remova1 of reproductive sinks (seed pods) and the amount of these proteins increases accordingly (for review, see Staswick, 1994). Other changes …

Models To Predict Yield Loss Due To Weeds In Rice Ecosystems, John L. Lindquist

Department of Agronomy and Horticulture: Faculty Publications

Yield loss models have been developed and evaluated for irrigated rice ecosystems with respect to effects of Echinochloa crusgalli. Simple regression models that give the relation between yield loss and weed density or relative leaf area are discussed with respect to their practical value in weed management in rice. More complex eco-physiological process models have been developed and used for rice ecosystems as well. Such models can be useful as a tool in research, whereas more simple approaches are needed for practical application in weed management.

Systematic Anatomy Of Euphorbiaceae Subfamily Oldfieldioideae I. Overview, W. John Hayden

Biology Faculty Publications

The biovulate subfamily Oldfieldioideae of Euphorbiaceae, characterized by spiny pollen, is an otherwise apparently diverse assemblage of mostly Southern Hemisphere trees and shrubs that traditionally have been allied with genera of Phyllanthoideae and Porantheroideae sensu Pax and Hoffmann. Although fairly diverse anatomically, the following structures characterize the subfamily with only a few exceptions: pinnate brochidodromous venation with generally randomly organized tertiary and higher order venation; foliar and petiolar glands absent; unicellular or unbranched uniseriate trichomes; latex absent; mucilaginous epidermis or hypodermis; brachyparacytic stomata; vessel elements with simple perforation plates and alternate, often very small, intervascular pits; thick-walled nonseptate imperforate tracheary …

Stem Development, Medullary Bundles, And Wood Anatomy Of Croton Glandulosus Var. Septentrionalis (Euphorbiaceae), Sheila M. Hayden, W. John Hayden

Biology Faculty Publications

Anatomy and development of vascular tissues in the annual stems of Croton glandulosus var. septentrionalis are described. In primary stages of growth the stem possesses a eustele of bicollateral bundles; international phloem is notably more extensive than the external. In addition to a vascular cambium and secondary xylem that form in the usual fashion, additional cambia add cells to the internal phloem portion of the bicollateral bundles, forming well-marked medullary bundles at the perimeter of the pith. At first, the perimedullary cambial strands produce only internal secondary phloem; later, internal secondary xylem is present, the medullary bundles have an inverted …

Miscellaneous Publication 42/93 - Development And Dissemination Of Design Methods For Rangeland Paddocks Which Maximise Animal Production And Minimise Land Degradation, Shane Cridland, Mark Stafford Smith

Animal production and livestock published reports

Surveys of rangeland resources in Western Australia to date have shown that 23% of the area surveyed is in poor range condition. Poor condition is characterised by the loss of perennial vegetation allowing wind and water erosion. Approximately another 37% is in only fair range condition (Curry and Hacker 1990).

The loss of range condition is partly due to uneven use of paddocks by sheep and cattle. The areas close to water and the preferred pasture types are often over-utilised, while areas well away from water and less preferred pasture types are under-utilised. The result is that rangeland in good, …

Effect Of Organic Matter Decomposition Level On Bacterial Species Diversity And Composition In Relationship To Pythium Damping-Off Severity, Michael J. Boehm, L.V. Mdden, H.A.J. Hoitink

Department of Plant Pathology: Faculty Publications

Rhizosphere bacteria were isolated from root tip segments of cucumber seedlings grown in a suppressive, slightly decomposed light-colored peat mix, a conducive, more decomposed dark-colored peat mix, and a suppressive dark peat mix amended with composted hardwood bark. The bacteria were identified by a gas chromatographic fatty acid methyl ester analysis. The total number of taxa recovered from a single root tip segment ranged from 9 to 18. No single taxon predominated on all root tip segments harvested from any of the mixes. The highest relative population density reached by a given taxon on any root tip segment was 45%. …

The Role Of The Seed Coat In The After-Ripening Process Of American Pokeweed (Phytolacca Americana L.), Jason E. Cox

Honors Theses

As plants evolve into new forms and shapes, the reproductive structures are often the last to change because of the importance of successful reproductive organs to the survival of the plant's hereditary information. Because of this particular feature, one very common method of determining how advanced a species is evolutionarily is the study of its reproductive cycle (Gifford and Foster, 1989). A few advanced classes, most notably the general class groupings of the Gymnosperms and Angiosperms, have developed seeds as a part of their reproductive cycle. Normally, there are several stages through which the seed must go in order for …

Establishment Of Lupin Seedlings, Miles Dracup

Journal of the Department of Agriculture, Western Australia, Series 4

Good seedbed conditions lead to high and rapid seedling emergence and vigorous seedlings best equipped to avoid disease, weed competition and sand-blasting. Good establishment is needed for a high yielding crop.

In Western Australia, seedbed moisture and temperature are most likely to limit successful emergence of lupins, especially with the trend toward early sowing.

Research by the Department of Agriculture is helping to define seedbed temperature and moisture requirements for successful lupin establishment that will help future research for improving seedbed conditions.

Production Of High-Value Wheats : One Sustainable Answer To The Cost:Price Squeeze, Wal Anderson, Alan Peggs, Doug Sawkins

Journal of the Department of Agriculture, Western Australia, Series 4

Farmers and scientists alike over the past decade have sought to address the declining terms of farm trade (the cost.price squeeze) by increasing wheat yields in ways that will ensure both their economic and ecological survival. Nevertheless, costs have continued to increase as a proportion of the value of the product.

Many farmers have increased their wheat yields substantially and the industry as a whole is more conscious of the quality of its product.

Over the past 10 years or more there has been intense interest in, and considerable adoption of. conservation farming techniques such as minimum tillage, residue retention, …

Vascular Flora Of Three Watersheds In The Fernow Experimental Forest And Factors Influencing Species Composition Of The Herbaceous Layer, Staci Dudash Smith Aulick

Theses, Dissertations and Capstones

Herbaceous layer communities respond to a number of environmental variables in forests: thus, study of the herb layer is essential for a more complete understanding of the forest ecosystem. The objectives of this study were to (1) describe the flora of the watersheds. (2) describe the species richness and diversity of watersheds 3, 4 , and 7 of the Fernow Experimental Forest, Parsons, West Virginia, and (3) examine stand and soil variables and their influence on the herbaceous communities or the forest. Watersheds were selected on the basis of stand age/history (WS3 "20yr, clearcut; WS7 "20 yr. clearcut and herbicide: …

Effect Of Light, Nitrogen, And Water Management On Rice (Oryza Sativa) Tolerance To Fenoxaprop, Roy J. Smith Jr., Aurora M. Baltazar, Paolo Nastasi

Journal of the Arkansas Academy of Science

The effect of light intensity, nitrogen (N), and water management on rice (Oryza sativa cv. 'Newbonnet' and 'Lemont') tolerance to fenoxaprop {(+)-2-[4[(6-chloro-2-benzoxazolyl)oxy]phenoxy]propanoic acid} was determined in two field studies at the Rice Research and Extension Center, Stuttgart, AR, in 1988 and 1989. In one study, 'Newbonnet' rice was treated with 0.22 kgai ha-1fenoxaprop at 0, 1, 3, 5, 7, 10, 14, and 28 days after N application and flooding. Moderate to severe foliar chlorosis, stunting, and stand and yield reductions occurred when fenoxaprop was applied within 7 days after N application and flooding. None to slight injury or yield reduction …