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The Identification, Distribution, Impacts, Biology And Management Of Noxious Rangeland Weeds, Roger L. Sheley Oct 1994

The Identification, Distribution, Impacts, Biology And Management Of Noxious Rangeland Weeds, Roger L. Sheley

All U.S. Government Documents (Utah Regional Depository)

This document provides a discussion of the biology and management of exotic rangeland weeds which are a threat to native ecosystems of the western United States. Chapter 1 describes a generalized approach for managing noxious weed infested rangeland, while Chapter 2 focuses on preventing noxious weed invasion. In some cases, noxious weeds readily invade riparian areas, and because of the sensitive nature of these ecosystems Chapter 3 is devoted to riparian weed management. The following 13 chapters describe the identification, origin, history, distribution, potential invasion, impacts, biology and ecology, and management of specific noxious rangeland weeds.


Nebline, October 1994 Oct 1994

Nebline, October 1994

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Horticulture

Rural $ense

Human Resources

4-H & Youth

Environmental Focus

Community & Leadership Development

Extension Calendar

Expanded Food and Nutrition Education Program (EFNEP)

Nebraska Association for Family and Community Education News

and other extension news and events


The Effect Of Nitrogen Fertilization On The Phenology Of Roots In A Barrier Island Sand Dune Community, Everett P. Weber Oct 1994

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 …


Aboveground Biomass And Net Primary Production Along A Virginia Barrier Island Dune Chronosequence, John Joseph Dilustro Oct 1994

Aboveground Biomass And Net Primary Production Along A Virginia Barrier Island Dune Chronosequence, John Joseph Dilustro

Biological Sciences Theses & Dissertations

Aboveground biomass was examined along a chronosequence of dune communities on Hog Island, a Virginia Coast Reserve LTER site. The dominant species were Ammophila breviligulata and Spartina patens. Aboveground biomass was harvested monthly from ten quadrats on dunes 6, 24, 36, and 120 years old. Sampling was conducted from April to November 1993. Biomass values were greater for younger dunes. Total aboveground biomass decreased with increasing site age and ranged from 152 g m-2 on the 120 year old dune to 205 g m-2 on the 6 year old dune in October 1993. Spartina patens biomass was …


The Prairie Naturalist Volume 26. No. 3. September 1994 Sep 1994

The Prairie Naturalist Volume 26. No. 3. September 1994

The Prairie Naturalist

BREEDING RANGE AND POPULATION STATUS OF LESSER PRAIRIE-CHICKENS IN COLORADO ▪ K. M. Giesen

LESSER PRAIRIE-CHICKEN MOVEMENTS AND HOME RANGES IN NEW MEXICO ▪ T. Z. Riley, C. A. Davis, M. A. Candelaria, and H. R. Suminski

WATERFOWL PRODUCTIVITY AND USE OF NESTING STRUCTURES IN THE PRAIRIE POTHOLE REGION ▪ R. R. Johnson, K. F. Higgins, I. J. Ball. and S. C. Kohn

A COMPARISON OF PERCH USE BY VOCALIZING EASTERN AND WESTERN MEADOWLARKS ▪ K. A. Kinstler and T. A. Sordahl

FARM OPERATOR ATTITUDES TOWARD WHITE-TAILED DEER AT SAND LAKE NATIONAL WILDLIFE REFUGE, SOUTH DAKOTA ▪ D. E. Naugle. …


Nebline, August 1994 Aug 1994

Nebline, August 1994

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Horticulture

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4-H & Youth

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1994 Lancaster County Fair Edition


Patterns Of Isozyme Variation In Relation To Population Size, Isolation, And Phytogeographic History In Royal Catchfly, Rebecca W. Dolan Aug 1994

Patterns Of Isozyme Variation In Relation To Population Size, Isolation, And Phytogeographic History In Royal Catchfly, Rebecca W. Dolan

Scholarship and Professional Work - LAS

The distribution of genetic variation within and among plant populations is influenced by both contemporary and historical factors. I used isozyme analysis of band phenotypes to examine genetic structure in the rare prairie forb Silene regia. Relationships between current-day population size, isolation, and phenotypic variation were assessed for 18 populations in two regions with differing postglacial history. Western populations from unglaciated southern Missouri and Arkansas were more genetically diverse based on the Shannon-Weaver index (H) and a polymorphic index than were more eastern populations. These differences may be due to loss of variation with repeated founding of new populations in …


Proceedings Of A Symposium On Sustaining Rangeland Ecosystems, W. Daniel Edge, Sally L. Olson-Edge Aug 1994

Proceedings Of A Symposium On Sustaining Rangeland Ecosystems, W. Daniel Edge, Sally L. Olson-Edge

Aspen Bibliography

No abstract provided.


Living Mulches Suppress Aphids In Broccoli, Michael J. Costello, Miguel A. Altieri Jul 1994

Living Mulches Suppress Aphids In Broccoli, Michael J. Costello, Miguel A. Altieri

Horticulture and Crop Science

A living mulch combines an annual crop with a cover crop to provide pest control and soil protection. Results of a study in the Salinas Valley show cabbage aphid infestation can be lowered on broccoli grown in living mulches compared to clean cultivation, possible because light reflectance patterns are less attractive to incoming aphids. Early and intense mowing of the cover crop and adequate irrigation maintained broccoli yield in living mulches relative to clean cultivation. Lack of specialized equipment is the main limitation to the commercial application of living mulches at this time.


Nebline, July 1994 Jul 1994

Nebline, July 1994

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Horticulture

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Human Resources

4-H & Youth

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Community & Leadership Development

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Nitrous Oxide Flux From Poultry-Manured Erosion Plots And Grass Filters After Simulated Rain, Mark S. Coyne, R. A. Gilfillen, Robert L. Blevins Jul 1994

Nitrous Oxide Flux From Poultry-Manured Erosion Plots And Grass Filters After Simulated Rain, Mark S. Coyne, R. A. Gilfillen, Robert L. Blevins

Plant and Soil Sciences Faculty Publications

Adding carbon-rich materials to fields, like manure, may enhance denitrification. Grass filters, which are used to trap surface runoff from these fields, may also provide a carbon-rich environment that favors water infiltration and denitrification. Nitrous oxide (N2O) may be evolved these settings. It is a radiatively important trace gas and intermediate in the denitrification pathway and several other microbial processes. We measured N2O flux, after simulated rain, using a soil cover technique in poultry-manured plots and grass filters receiving their runoff. Intact soil cores were used to relate the N2O flux to the denitrification …


Evaluation And Utilization Of Biodiversity In Triticeae For Wheat Lmprovement, A. B. Damania, J. Valkoun Jun 1994

Evaluation And Utilization Of Biodiversity In Triticeae For Wheat Lmprovement, A. B. Damania, J. Valkoun

Herbarium Publications

To adapt new varieties to a wide spectrum of environments breeders and farmers have emphasized the need for broadening the current narrow genetic base of modern varieties of important cereal crops such as wheat and barley. In response to this need, several thousand samples of indigenously cultivated Triticeae species and their wild relatives have been collected from the centers of diversity. However, gene bank collections are of little use if they are not evaluated and the information disseminated widely. Evaluation is essentially the link between conservation and use. Some of the collected material has been evaluated at the International Center …


Attempts To Produce Alien Addition Lines In Triticum Durum, Domenico Pignone Jun 1994

Attempts To Produce Alien Addition Lines In Triticum Durum, Domenico Pignone

Herbarium Publications

Aneuploid stocks in durum wheat are few, and alien additions are particularly rare. The present contribution describes the results of a program aimed at the addition of alien chromosomes to tetraploid wheat. Aegilops caudata, Ae. longissima and Dasypyrum villosum were used as chromosome donors. The crossing program involved the production of amphidiploids with the wheat cytoplasm and the recurrent crossing with durum wheat pollen. IS monosomic addition (2n= 29) plants were obtained and partly selfed and/or backcrossed to wheat. Two disomic addition (2n = 30) plants, possessing two different Ae. caudata chromosomes, were obtained; unfortunately they were very weak and …


Forage Species In Xinjiang Northern Natural Grasslands: Grasses, Li Bao-Jun Jun 1994

Forage Species In Xinjiang Northern Natural Grasslands: Grasses, Li Bao-Jun

Herbarium Publications

Forage germplasm resources, their distributions, potential agronomic characteristics and genetic aspects of the perennial grasses originating in Xinjiang northern regions are discussed. Grass diversity in the natural grasslands is immense for the range of environments to which it is endogenously adapted. Among the perennial species in the mountain area are summer growing and winter-dormant ecotypes, whereas in the plain outland summer-fast-growing, summer-dormant and winter dormant ecotypes occur. Flowering uniformity within the grass tribe provides the chance for gene exchange. The genetic variation for growth rate, tiller development, regrowth and yield between species and within a species has provided plant breeder …


Proceedings Of The 2nd International Triticeae Symposium, Richard R.-C. Wang, Kevin B. Jensen, Carolyn Jaussi Jun 1994

Proceedings Of The 2nd International Triticeae Symposium, Richard R.-C. Wang, Kevin B. Jensen, Carolyn Jaussi

Herbarium Publications

At the First International Triticeae Symposium, Helsingborg, Sweden, July 29-August 2, 1991, the participants decided that subsequent meetings will be held every three years. Thus, the Second International Triticeae Symposium was held in Logan, Utah, U.S.A, June 20-24, 1994, with USDA Agricultural Research Service's Forage and Range Research Laboratory and Utah State University as hosts.

The purposes of the second symposium were: (I) to exchange the latest scientific information and advancements related to annual and perennial Triticeae species; (2) to promote the exchange of ideas for developing coordinated collaborative research; and (3) to provide an opportunity to see the biodiversity …


Triticeae: A Tribe For Food, Feed And Fun, Roland Von Bothmer, Björn Salomon Jun 1994

Triticeae: A Tribe For Food, Feed And Fun, Roland Von Bothmer, Björn Salomon

Herbarium Publications

Triticeae is an important tribe in the grass family, Poaceae. It contains the cereals wheat, rye, triticale, and barley as well as a large number of wild species, some of which are utilized as forage grasses. The tribe combines all kind of biological mechanisms and genetic systems: diploids and polyploids; annuals and perennials, inbreeders and outbreeders, and even apomicts. Due to this large variation Triticeae is an excellent model group for research in genetics, plant breeding, genetic diversity, taxonomy, and speciation in plants.

Triticeae is distributed in almost all temperate areas of the world and consists of some 350-450 species …


Plant Germplasm Resources, S. A. Eberhart, H. E. Bockelman Jun 1994

Plant Germplasm Resources, S. A. Eberhart, H. E. Bockelman

Herbarium Publications

Landraces and wild relatives of crops from centers of diversity have been rich sources of resistance to new pathogens, insect pests, and other stresses as well as for traits to improve food and fiber quality, animal feed, and industrial products. Because very few crops grown in the U.S. are native, plant introductions are vital to our agriculture. The National Plant Germplasm System (NPGS) was established to acquire, preserve, and distribute plant genetic resources from around the world so that scientists have immediate access to these source materials. The active collection is maintained and distributed by 19 national germplasm repositories. The …


The Prairie Naturalist Volume 26, No. 2. June 1994 Jun 1994

The Prairie Naturalist Volume 26, No. 2. June 1994

The Prairie Naturalist

EARLY HISTORY OF THE NORTH DAKOTA NATURAL SCIENCE SOCIETY ▪ J. T. Lokemoen

TEMPORAL VARIATION IN COYOTE PREY IN TALLGRASS PRAIRIE OF EASTERN KANSAS ▪ D. E. Brillhart and D. W. Kaufman

DIFFERENCES IN USE OF INTERSPERSED WOODLAND AND GRASSLAND BY SMALL MAMMALS IN NORTHEASTERN KANSAS ▪ B. R. McMillan and D. W. Kaufman

THE CIRCANNUAL MASS CYCLE IN THREE POPULATIONS OF THIRTEEN-LINED GROUND SQUIRREL ▪ G. Y. Walker, O. A. Schwartz, and J. E. Joy

SUMMER ELK TRAPPING IN SOUTH DAKOTA ▪ J. J. Millspaugh, G. C. Brundige, and J. J. Jenks

OUT-OF-SEASON BIRTHS OF ELK CALVES IN WYOMING …


Symbiotic Seed Germination Of Platanthera Integrilabia (Correll) Luer, An Endangered Terrestrial Orchid, Lawrence William Zettler May 1994

Symbiotic Seed Germination Of Platanthera Integrilabia (Correll) Luer, An Endangered Terrestrial Orchid, Lawrence William Zettler

All Dissertations

No abstract provided.


The Response Of Five Tropical Plant Species To Natural Solar Ultraviolet-B Radiation, Peter S. Searles May 1994

The Response Of Five Tropical Plant Species To Natural Solar Ultraviolet-B Radiation, Peter S. Searles

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Tropical regions currently receive the highest global levels of solar ultraviolet-B radiation (UV-B, 280-320 nm) even without ozone depletion. Thus, the influence of natural, present-day UV-B irradiance in the tropics was examined for five tropical species, including three native rainforest tree species and two economically important species. Solar UV-B radiation conditions were obtained vi using either a UV-B excluding plastic film or a near-ambient UV-B transmitting film in a small clearing on Barro Colorado Island (BCI), Panama (9 ° N). Significant differences were often exhibited as increased foliar UV-B absorbing compounds, increased leaf mass per area, and reduced leaf blade …


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 Apr 1994

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 …


Predicting Evolutionary Consequences Of Greater Reproductive Effort In Tripsacum Dactyloides, A Perennial Grass, Laura L. Jackson, Chester L. Dewald Apr 1994

Predicting Evolutionary Consequences Of Greater Reproductive Effort In Tripsacum Dactyloides, A Perennial Grass, Laura L. Jackson, Chester L. Dewald

Faculty Work

To test the prediction that a mutation causing greater reproductive effort will result in reduced vegetative vigor, we compared the seed production, growth, and carbohydrate status of normal and pistillate genotypes of the grass Tripsacum dactyloides differing in seed production by up to fourfold. We evaluated the costs of reproduction by two methods: experimental manipulation of reproductive effort and comparison of high and low-yielding genotypes. Despite the large difference in seed production, normal and pistillate (high-yielding) genotypes did not differ in growth rate over a 1-yr period. Contrary to predictions, carbohydrate reserves in the high-yielding genotype were significantly higher at …


Biosystematics And Diversification In The Genus Striga Lour. (Scrophulariaceae) In Africa, Kamal-Eldin Ibrahim Mohamed Apr 1994

Biosystematics And Diversification In The Genus Striga Lour. (Scrophulariaceae) In Africa, Kamal-Eldin Ibrahim Mohamed

Biological Sciences Theses & Dissertations

Of the 34 taxa of Striga (29 species) that occur in Africa, 25 are endemic. Species diversity differs from region to region. The subtropical zone has 74% of the taxa including 41% endemics. Within this region, the West African part (from Senegal to eastern Nigeria) has 62% of the total taxa including 24% endemics. South of the equator the number of taxa is 56% of the total with 21% endemics, a proportion slightly less than that for West Africa. I recognize 29 species based on extensive herbarium and field studies. A new species from Angola is described. Striga yemenica previously …


Nebline, March 1994 Mar 1994

Nebline, March 1994

NEBLINE Newsletter Archive from Nebraska Extension in Lancaster County

Horticulture

Rural $ense

Human Resources

4-H & Youth

Environmental Focus

Community & Leadership Development

Extension Calendar

Expanded Food and Nutrition Education Program (EFNEP)

Nebraska Association for Family and Community Education News

and other extension news and events


Bulletin 4283 - Nitrogen Fertilisers For Cereal Production, M. G. Mason Mar 1994

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 …


The Prairie Naturalist Volume 26. No. 1. March 1994 Mar 1994

The Prairie Naturalist Volume 26. No. 1. March 1994

The Prairie Naturalist

FISH CATCHES WITH HOOP NETS OF TWO DESIGNS IN THE LARAMIE RIVER, WYOMING ▪ W. A. Hubert and T. M. Patton

LENGTH DISTRIBUTIONS OF NORTHERN PIKE CAUGHT IN FIVE GILL NET MESH SIZES ▪ R. M. Neumann and D. W. Willis

EVALUATION OF LARGEMOUTH BASS SLOT LENGTH LIMITS IN TWO SMALL SOUTH DAKOTA IMPOUNDMENTS ▪ R. M. Neumann, D. W. Willis, and D. D. Mann

POSSIBLE PREDATION OF A FORSTER'S TERN CHICK BY A SNAPPING TURTLE ▪ G. Fraser

SMALL MAMMAL DIVERSITY AND ABUNDANCES IN THREE CENTRAL IOWA GRASSLAND HABITAT TYPES ▪ L. A. Hayslett and B. J. Danielson

SMALL …


Fundamental Principles Of Plant Pathology For Agricultural Producers, Paul C. Vincelli Mar 1994

Fundamental Principles Of Plant Pathology For Agricultural Producers, Paul C. Vincelli

Agriculture and Natural Resources Publications

All crop plants produced in Kentucky have the potential to become diseased under certain conditions. Diseases of crops can affect yield and/or quality of the harvested commodity. This can impact profitability and increase the risks of farming.

A plant is diseased when it is affected by some agent that interferes with its normal development. Some disorders are caused by noninfectious factors, such as temperature extremes or nutrient deficiencies. However, this publication focuses on diseases caused by infectious microorganisms.

Diseased plants exhibit a variety of symptoms. These can include stunting, yellowing, wilting, twisting, reddening, browning, blighting, root rot, fruit rot, …


Delaying The Development Of Herbicide Resistant Ryegrass By Using Alternative Weed Control Strategies, A. J. Diggle, G. S. Gill, J. E. Holmes Mar 1994

Delaying The Development Of Herbicide Resistant Ryegrass By Using Alternative Weed Control Strategies, A. J. Diggle, G. S. Gill, J. E. Holmes

Biosecurity published reports

Alternative strategies to control ryegrass in wheat lupin rotations are worth approximately 15 dollars per hectare for each 50% reduction achieved in plant or seed numbers. This figure has been calculated for circumstances similar to those found at Wongan Hills, and it holds in all cases where ryegrass is still under control using standard herbicides.

Farmers should adopt any ryegrass strategy in addition to that normally practised, so long as the cost to control ratio is less than $15/ha/50% kill. This applies even where good control is being achieved using grass selective herbicides, regardless of the number of previous applications …


Wild Medicine: Review Of Medicinal Wild Plants Of The Prairie By Kelly Kindscher, Kathleen H. Keeler Mar 1994

Wild Medicine: Review Of Medicinal Wild Plants Of The Prairie By Kelly Kindscher, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

I am highly enthusiastic about this book as a reference work. It summarizes the literature on the medicinal uses for more than 103 prairie plants. For 43 species, Kindscher gives common, Indian, and scientific names; description; habitat; parts used; Indian uses; medical history; scientific research and cultivation; and information on about 100 of their relatives. Another 60 entries are condensed to 24 paragraphs. Full-page line drawings by William S. Whitney of the major species are generally excellent, and all 103 entries have distribution maps. The introduction discusses the region covered, with helpful maps. There's an index, a glossary and a …


Harvesting Hay For High Yield And Quality — More On Bale Ventilators And Other Harvest Aids, Michael Collins Feb 1994

Harvesting Hay For High Yield And Quality — More On Bale Ventilators And Other Harvest Aids, Michael Collins

Kentucky Alfalfa and Stored Forage Conference

In some areas of the country, producers store a substantial portion of their forage for winter feeding as silage or haylage. However, hay remains the most popular storage method for forage. Hay stores well for long periods and is better suited to cash sale and transportation than silage. Mechanical conditioning, which gained acceptance during the 1950's is probably still the greatest single change in hay harvesting and storage technology during this century. However, a number of other noteworthy changes and innovations have occurred in recent years which have helped to reduce the extent of losses during hay harvesting and storage. …