Weed Science Commons^™

Habitat-Related Differences In Necroph- Ilous Species Composition: Implications For Resource Competition, Adrienne L. Conley, Elisabeth K. Jorde, Rachel E. Jorde, Lauren K. Yares, Kenzie K. Lee, Carrie L. Hall, Daniel R. Howard

The Prairie Naturalist

Competition for resources is one of the most important selective factors influencing the expression of life history traits in both plants and animals (Darwin 1859). In grasslands, competition for resources such as nutrients, water, and space often is constrained by stochastic processes (Axelrod 1985). Disturbance factors such as fire, grazing by large herbivores, and fluctuating climatic conditions tend to alter the structure and magnitude of competition for limited resources among grassland communities more frequently than in other ecosystems (Snaydon 1987, van der Maarel 1993). Vertebrate carrion is one important resource used by both plants and animals in grasslands, providing a …

Comparison Of Two Trap Net Designs For Sampling Muskellunge, Brian G. Blackwell, Todd M. Kaufman, Tyrel S. Moos, David O. Lucchesi

The Prairie Naturalist

Sampling adequate numbers of muskellunge (Esox masquinongy) is necessary to evaluate stocking success and to collect information on various population metrics (e.g., growth, condition, relative abundance). However, muskellunge are often difficult to sample with standard fish sampling gears. We collected muskellunge in trap nets of two different designs (large trap nets [1.5-m × 1.8-m frames, 1.5-m diameter hoops, double throated, single 1.5-m × 30.5-m lead and 19-mm knotless mesh] and small trap nets [0.9-m × 1.5-m frames, 0.9-m diameter hoops, single throat, single 0.9-m × 15.2-m lead and 19-mm knotted mesh]. We also estimated abundance of muskellunge (>600 mm …

Using Otolith Microchemistry To Classify Yellow Perch As Stocked Or Naturally Produced, Andrew K. Carlson, Matthew J. Ward, Brian D.S Graeb

The Prairie Naturalist

Fisheries managers routinely use stocking to supplement fish populations (Schramm and Piper 1995, Fisher 1996). Stocking eyed-eggs offers substantial cost savings compared to stocking fry and fingerlings (PFBC 2011); however, traditional stocking evaluation using oxytetracycline (OTC) marking of otoliths is ineffective for eyed-eggs of some species (e.g., yellow perch, [Perca fla- vescens]). Thus, there is a need for additional approaches to be able to classify fish as stocked or naturally produced. Fish otoliths are paired calcified structures in the inner ear that permanently deposit trace elements in proportion to water column concentrations (Campana 1999, Campana et al. 2000). Coupled with …

Background Paper On Systematics, Invasive Species Advisory Committee

National Invasive Species Council

The Invasive Species Advisory Committee (ISAC) makes recommendations to the Federal government agencies that have an invasive species portfolio. This systematics recommendation strives to motivate action in the agencies that have been identified in the Situation Report as the agencies with systematics capabilities in the Federal government.

The USDA Agricultural Research Service (ARS) and the Smithsonian Institution are repositories of a large amount of the systematics collections and human capabilities for systematics essential work on invasive species. Conducting the Survey of their systematics capabilities and needs is urgent. The Survey will describe actions in research, specimen-based collections, a biodiversity informatics …

Plant Diversity Affects Performance Of Invasive Thistles In Restored Nebraska Grasslands, Katilyn J. Price

School of Natural Resources: Dissertations, Theses, and Student Research

Invasive plant species threaten native grasslands, affecting nutrient cycling, biodiversity, wildlife habitat, and usable land for production. Consequently, preventing establishment of invasive species is critical before removal becomes difficult and expensive. The purpose of this study was to examine the effects of grassland plant diversity on musk thistle (Carduus nutans) and Canada thistle (Cirsium arvense) establishment and determine which environmental factors (light penetration, soil moisture, plant diversity, and soil nitrogen) account for resistance to invasions. In a field experiment at The Nature Conservancy’s Wood River site (Nebraska), the two invasive thistle species were planted into replicated …

Restoration Strategies To Migrate Shrub Encroachment Into Coastal Prairies, Erick Mark Verderber

Theses and Dissertations - UTB/UTPA

Shrub encroachment into grasslands is a phenomenon facilitated by fire suppression, climate warming, and overgrazing of grasses by cattle, and if left unmanaged, can alter ecosystem structure and function. In this study, I compare the effectiveness and cost/benefit of various restoration strategies (prescribed fire, mechanical, and chemical) used singly and in different combinations at decreasing two shrubs, honey mesquite (Prosopis glandulosa Torr.) and huisache (Acacia farnesiana (L.) Willd.), and promoting growth and survival of gulf cordgrass (Spartina spartinae (Trin.) Merr. ex Hitchc.), the dominant coastal prairie grass within the Laguna Atascosa National Wildlife Refuge-Bahia Grande Unit in deep south Texas. …

Historical Common Names Of Great Plains Plants, With Scientific Names Index. Volume I: Common Names, Elaine Nowick

Zea E-Books Collection

Containing thousands of entries of both vernacular and scientific names of Great Plains plants, the literature that informs this exhaustive listing spans nearly 300 years. Author Elaine Nowick has drawn from sources as diverse as Linnaeus, Lewis and Clark, and local university extension publications to compile the gamut of practical, and often fanciful, common plant names used over the years. Each common name is accompanied by a definitive scientific name with references and authority information. Interspersed with scientifically-correct botanical line drawings, the entries are written in standard ICBN format, making this a useful volume for scholars as well as lay …

Historical Common Names Of Great Plains Plants, With Scientific Names Index. Volume Ii: Scientific Names Index, Elaine Nowick

Zea E-Books Collection

Containing thousands of entries of both vernacular and scientific names of Great Plains plants, the literature that informs this exhaustive listing spans nearly 300 years. Author Elaine Nowick has drawn from sources as diverse as Linnaeus, Lewis and Clark, and local university extension publications to compile the gamut of practical, and often fanciful, common plant names used over the years. Each common name is accompanied by a definitive scientific name with references and authority information. Interspersed with scientifically-correct botanical line drawings, the entries are written in standard ICBN format, making this a useful volume for scholars as well as lay …

Biology And Control Of Glyphosate-Resistant Giant Ragweed, Simranpreet Kaur

Department of Agronomy and Horticulture: Dissertations, Theses, and Student Research

Giant ragweed is a troublesome, early emerging, summer annual weed found throughout the eastern and midwestern corn and soybean growing regions of the United States. Since the emergence of giant ragweed varies at different locations, our first objective was to determine the emergence pattern of giant ragweed in Nebraska and how spring tillage influences emergence. Results of a two-year study suggested that giant ragweed emerged from late March until mid-June, with the majority of emergence ceasing by early May. Spring tillage could be used as an alternative method for managing glyphosate resistant giant ragweed.

Water stress can affect the growth …

Productivity And Biological Nitrogen Fixation Of Different Species Of Vetches (Vicia Spp.) Under The Rainfed Conditions Of West Asia, Ali Abd El Moneim, Mohan C. Saxena

IGC Proceedings (1977-2023)

The low rainfall areas of West Asia are characterized by pastoral production system primarily based on small ruminants (sheep and goats). Rangelands serve as the main source of feed. With increasing population, the demand for livestock products has increased. As a consequence, the stocking rates have soared, increasing the pressure on rangelands. Rangeland degradation has therefore been increasing threatening the sustainability of livestock production system and the livelihood of the people dependent on it. Production of additional feed is essential to reduce the pressure on rangelands. Vetches (Vicia spp.) are endemic in the area and can be potential source …

Livestock Production From Grasslands With Improved Management Compared To Traditional Management, Florian Leiber

IGC Proceedings (1977-2023)

The value of traditional versus improved management systems for grassland is discussed. The set target is the persistence of the ecological, economic and social multifunctionality of grasslands and the increase of food output from these areas without increasing parallel requirements for arable crop or energy inputs. Based on the fact that historically traditional systems were stable and sustainable in many cases, while severe damage is faced nowadays, it is argued that lot of improvement should be based on the acknowledgment of successful traditional practises. The challenge might rather be to define improvement as a contemporary development of traditional techniques. The …

Potential Of Forages In Crop Diversification And Crop Rotation, Martin H. Entz, Joanne Thiessen Martens

IGC Proceedings (1977-2023)

Redesign of agricultural systems according to ecological principles has been proposed for the development of sustainable systems. We review a wide variety of ecologically-based crop production practices that focus on forage crops in farming systems and discuss their potential role in enhancing the profitability, environmental sustainability and resilience. Crop-livestock systems that most closely mimic natural systems through appropriate integration of diverse components appear to offer the greatest potential benefits. These systems are more energy efficient and combine high productivity with low ecological footprint. Greater understanding of ecological relationships within crop-livestock systems are required to purposefully and proactively redesign agricultural systems …

Forage Seed Quality: Dormancy, Standards And Quarantine, John G. Hampton

IGC Proceedings (1977-2023)

There are many dimensions to the concept of seed quality. Viable seed which will not germinate when provided with all the requirements for germination is dormant. Forage grasses mostly exhibit non-deep physiological dormancy (PD), while physical dormancy (PY) is common in forage legumes where imbibition is prevented by the seed coat’s impermeability to water (hard seed). Methods for breaking PD and PY to allow germination testing and/or crop establishment are discussed.

In the seed industry seed quality standards are an important feature of quality assurance and may apply for seed production contracts, seed certification, seed sale and seed importing. Standards …

Quality Seed Production And Effective Marketing Systems For Development Of Grasslands, M. Philip Rolston

IGC Proceedings (1977-2023)

Seed quality is defined as (i) maintaining genetic purity using seed certification principles (generation system; isolation; previous cropping history); (ii) achieving high levels of physical purity (especially low weed seed levels) by in field weed control and seed cleaning; (iii) achieving high levels of seed germination at harvest and maintaining germination through the seed supply chain. Seed production systems must not only produce high quality seed but also achieve economic seed yields. Seed crops have to be profitable (by being high yielding) to justify the investment of time and input costs to achieve quality. This in turn requires supporting research …

Scouting Benefits And Developing Innovations In Temperate Grassland To Sustainable Agriculture Production, Walter Ayala, Ethel Barrios, Ignacio Macedo, Jorge Sawchik, José A. Terra

IGC Proceedings (1977-2023)

Agricultural intensification raises concern about land use and future effects to natural resources. The world demand for grain, meat and forest products is increasing constantly. Changes are occurring at large scale, being a compromise for policy makers to contribute to identify opportunities to readdress the productive scenario. There is available technology to reduce impacts, without restricting necessarily productivity. Grasslands provide a large series of economical and ecological benefits to the agricultural systems, being the literature exhaustive in examples. Ley-farming and cover crops technologies are good examples of environmentally sound soil management practices. The society is also worried about an improper …

Evergraze: A Partnership Between Researchers, Farmers And Advisors To Deliver Effective Grassland Management, Warwick B. Badgery, Kate Sargeant, Michael A. Friend, Scott Glyde, Paul Sanford, Ralph Behrendt, Meredith L. Mitchell, Sean Murphy, Angela Avery

IGC Proceedings (1977-2023)

The profitable and sustainable management of livestock production from grassland systems is challenging and it can be difficult to develop a research structure that addresses farmer’s needs and has acceptable rigour and on-ground impact. This paper describes the attributes of research, development and extension (RD&E) programs that are required for a successful partnership between researchers, farmers and advisors. Insights are provided from the EverGraze program that designed, tested and implemented farming systems based on perennial pastures across southern Australia. With this project farmers and advisors were involved in setting research direction, designing experiments, providing strategic guidance over the management of …

Ecologically And Socially Sustainable Livestock Development In Marginal Areas, Ilse Köhler-Rollefson

IGC Proceedings (1977-2023)

“Marginal areas” are perceived as difficult and unproductive landscapes, always under the threat of drought, desertification and poverty. Yet, both dryland and high altitude marginal areas have an extraordinary output of livestock products; in the efficiency of producing human-edible protein they far surpass more fertile areas. This productivity under adverse climatic conditions rests on sophisticated strategies and social institutions developed by pastoral communities to deal with variability in the availability of resources. It depends on the use of animal genetic resources that are adapted to make best use of local vegetation and can cope with seasonal variations in availability. Livestock …

Valuing Variability--New Perspectives On Climate Resilient Dryland Development, Saverio Kratli

IGC Proceedings (1977-2023)

Valuing Variability is a challenge to the view of the drylands as naturally vulnerable to food insecurity and poverty. It argues that improving agricultural productivity in dryland environments is possible by working with climatic uncertainty rather than seeking to control it – a view that runs contrary to decades of development practice in arid and semi-arid lands.

Participatory And Holistic Approaches With Grassland Farmers And Development Of Policies, Alain Peeters

IGC Proceedings (1977-2023)

The world is changing rapidly. Grassland farmers and ruminant livestock breeders will have to adapt to these changing environmental, social and economic conditions. Research can help them at the condition that linear ‘top-down’ technology transfer methods are abandoned for the benefit of participatory and holistic approaches. These approaches classified in the generic term of ‘Farming System Research’ consider farmers as real research partners, and they merge farmer’s and scientist’s ideas with those of other stakeholder types. They combine scientist’s and farmer’s knowledge for creating fast innovations, easily adopted by farmers since farmers themselves contribute to their design and their development. …

Sustainable Grasslands: Resolving Management Options For Livelihood And Environmental Benefits, David R. Kemp, Warwick B. Badgery, David L. Michalk

IGC Proceedings (1977-2023)

To help solve the major issues of improving livelihoods and environmental services, grassland research needs to be evaluated within the context of relevant farm systems. Treatments need to show that they not only have significant effects but that they have effects that are meaningful in the context of the relevant farm system. Research often defines an optimum criterion for management that is a single point, but that is difficult to achieve in practice, especially when there are several components in a grassland system that need to be optimised. It is argued that an appropriate criterion for optimising management is a …

Climate Change Impact And Adaptation In Temperate Grassland And Livestock Industries, Afshin Ghahramani, Andrew D. Moore

IGC Proceedings (1977-2023)

Climate is projected to have negative impact on temperate grassland and livestock productions across the globe. Moderately elevated atmospheric CO₂ in the near future is expected to increase plant photosynthetic rates but this is likely to be limited by soil nitrogen deficits. However, in Australia at least it is unlikely that positive effect of elevated CO₂ on plant production be able to offset the negative impacts of climate change. Currently there is a considerable gap between actual and achievable production and profit in Australian grazing systems and many management and genetic improvements for climate adaptation would operate by …

Climate-Smart Brachiaria For Improving Livestock Production In East Africa: Emerging Opportunities, Sita R. Ghimire, Donald M. G. Njarui, Mupenzi Mutimura, Juan A. Cardoso, Linda Johnson, Elias M. Gichangi, Suliana Teasdale, Kennedy Odokonyero, John Caradus, Idupulapati M. Rao, Appolinaire Djikeng

IGC Proceedings (1977-2023)

Brachiaria grass is an important tropical forage of African origin with desirable attributes of agricultural and environmental significance. Brachiaria has been extensively cultivated as a pasture across the tropics except in its endemic provenance of Africa. In 2013, a collaborative research program was initiated in Kenya and Rwanda with the aim of improving the availability of quality livestock feeds adapted to drought and low fertility soils using Brachiaria. The outcomes sought were increased livestock productivity leading to improved farmer income and the development of seed production opportunities. The program has identified five preferred cultivars, and four of them are currently …

Tropical Grassland Ecosystems And Climate Change, C. R. Babu, Vivek Kr. Choudhary, Vijay Kumar

IGC Proceedings (1977-2023)

Grasses are unique group of flowering plants that form the foundation for the trophic structure in terrestrial communities. The grasses are found in every conceivable habitat where plants can thrive – from sea to deserts and from wetlands to peaks of highest mountains. The grasses form a distinct biome – a major ecological formation in the global classification of vegetation.

Recent Trends In Breeding Of Tropical Grass And Forage Species, J. S. Sandhu, Dinesh Kumar, Vijay Kumar Yadav, Tejveer Singh, R. P. Sah, Auji Radhakrishna

IGC Proceedings (1977-2023)

Germplasm enrichment in major tropical grasses and their characterization for emerging environmental challenges have been major focussed area in the recent past. Breeding efforts in tropical grasses are still limited to few selected species viz. Panicum spp, Cenchrus spp, Pennisetum spp and Bracharia spp and all other grasses use of land races for varietal development through selection have been major source of improvement. The pace of breeding efforts in the tropical grasses have been slowed because of many inherent characteristics viz. apomixis, poor seed set, high photo and thermo sensitivity often creating problem in designing and implementing an effective breeding …

Sustainability, Biodiversity And Environmental Issues: A Global Perspective For Livestock Production, David L. Michalk

IGC Proceedings (1977-2023)

To meet world food demand through the 21st century, agricultural production needs to increase, but this needs to be done sustainably through increasing efficiency, optimising sufficiency and achieving consistency, such that resource use is optimised, waste reduced and environmental benefits gained. These strategies need to be developed against changing food patterns, especially a decline in per capita consumption of cereals and an increase in meat consumption as household incomes increase. Grasslands are collectively the larger group of land-based ecosystems on the planet. Their values are not always recognised, often being seen as ‘reserves’ for exploitation for urban expansion, …

Wastelands Of The Mind: The Identity Crisis Of India’S Savanna Grasslands, Abi Tamim Vanak

IGC Proceedings (1977-2023)

The idea that wastelands are unproductive continues to be pervasive and is used by various agencies to gain control over marginal landscapes and remake them for productive purposes with dire results.

Grassland And Livestock Production: The East African Case, David Miano Mwangi

IGC Proceedings (1977-2023)

Grasslands cover over 26% of the world land mass and about 80% of the agricultural area. They are the source of a livelihood for about 1 million people in the developing countries. Livestock contributes 40% of the global value of agricultural outputs. Approximately 60% of rural households keep livestock. In East Africa there are a number of grasslands. The most extensive of these are the Acacia based Savanna grasslands. Others include the sudd flooded grasslands of South Sudan and the Miobo woodlands of Tanzania. More than 60% of the livestock and wildlife in this region are found on these grasslands. …

Three Is Company: Fixing The Grazing-Land Business Conundrum, Ralph Von Kaufmann

IGC Proceedings (1977-2023)

Grazing-lands have the largest footprint on the world’s land surface area but this is not reflected in the amount of business conducted on them. The most common land use systems are very land intensive, i.e., they use a lot of land to produce not very much and few jobs. The health of the planet depends on having healthy grazing-lands but there is a perfect storm brewing in which the demand from expanding pastoral communities for more food and jobs cannot be met just by applying good grazing-land management practices. Compatible businesses must be found that can create jobs without increasing …

Tropical Grasslands--Trends, Perspectives And Future Prospects, Panjab Singh

IGC Proceedings (1977-2023)

This paper attempts a rapid summary of the present day state of tropical grassland and livestock based production systems globally, especially in tropics, in relation to recent trends, future assessment, grassland rehabilitation and management strategies, future perspectives of grassland science and development including policy imperatives.

About Sponsors, National Organizing Committee, International Grassland Congress

IGC Proceedings (1977-2023)

No abstract provided.