Weed Science Commons^™

Predicting Invasive Range Of Eucalyptus Globulus In California, Anthony J. Lopez

Master's Theses

Eucalyptus globulus is the subject of intense debate in California. Its invasive potential, aggressive growth, reproductive biology, and association with fire make the prediction of spread important in California. Two modeling simulations, Climex and Maxent, will illustrate the distribution and potential growth range of E. globulus in California based on climate and presence. Modeling the potential range of growth will predict invasive spread. The anticipated result is the continued spread of E. globulus in coastal regions with adequate moisture and suitable climate. Predicting the range of E. globulus in California dictates management strategy and is key for preventing further introduction, …

Canola: A Modern Crop For A Modern Era, Kenneth J. Roché

Doctor of Plant Health Program: Dissertations and Student Research

The University of Nebraska-Lincoln Doctor of Plant Health program is a professional doctorate program with a comprehensive approach to plants and agriculture. The program emphasizes a broad interdisciplinary education across all plant-related disciplines, practical learning, research, and experience through internships. For my final required internship, I worked as a senior agricultural research intern with Research Designed for Agriculture (RD4AG) in Montana. RD4AG is a contract research organization based in Yuma, AZ with over thirty-years of experience. During my three month internship at RD4AG in Montana, a large portion of my responsibilities centered on managing regulated canola trials that were undertaken …

Assessing Multiple-Herbicide Resistance In A 2,4-D Resistant Waterhemp (Amaranthus Tuberculatus) Biotype From Nebraska: Student Research, Roberto Crespo

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

A waterhemp biotype was recently reported resistant to 2,4-D in Nebraska. In addition to the repeated use of 2,4-D, atrazine and imazathapyr were reported to be frequently used to control broadleaf weeds. Greenhouse experiments were conducted to confirm 2,4-D resistance and test for resistance to growth regulator herbicides and other herbicide modes-of-action (MoA). A single dose-response experiment showed reduced sensitivity in all three waterhemp biotypes to atrazine, imazethapyr and lactofen; therefore, they were generally considered resistant to those three herbicide MoA. None of the biotypes contained the Ser264 target-site mutation. Since the ametryn dose-response experiment resulted in all susceptible biotypes, …

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 …

A Real-Time Plant Discrimination System Utilising Discrete Reflectance Spectroscopy, Paul Symonds, Arie Paap, Kamal Alameh, J Rowe, C Miller

Research outputs 2014 to 2021

An advanced, proof-of-concept real-time plant discrimination system is presented that employs two visible (red) laser diodes (635. nm, 685. nm) and one near-infrared (NIR) laser diode (785. nm). The lasers sequentially illuminate the target ground area and a linear sensor array measures the intensities of the reflected laser beams. The spectral reflectance measurements are then processed by an embedded microcontroller running a discrimination algorithm based on dual Normalised Difference Vegetation Indices (NDVI). Pre-determined plant spectral signatures are used to define unique regions-of-classification for use by the discrimination algorithm. Measured aggregated NDVI values that fall within a region-of-classification (RoC) representing an …

Control Of Herbicide-Resistant Volunteer Corn In Herbicide-Resistant Soybean, Parminder Chahal

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

Volunteer corn is a problem weed in soybean fields because it reduces yield and seed quality, and potentially harbors insects, pests, and diseases. Several pre-packaged herbicides have been registered in soybean in recent years, but response of volunteer corn to these herbicides has not yet been documented. Therefore, the first objective of this study was to evaluate the response of glufosinate-, glyphosate-, and imidazolinone-resistant volunteer corn to 20 pre-emergence (PRE) and 17 post-emergence (POST) soybean herbicides. The results indicated that PRE soybean herbicides partially controlled (< 80%) volunteer corn except clomazone, while acetyl CoA carboxylase (ACCase) inhibiting herbicides provided ≥ 85% control. Germination and emergence are critical stages in weed seed establishment and persistence. Scientific literature is not available about the factors affecting germination and emergence of volunteer corn. The second objective was to determine the effects of different environmental and agronomic factors on the germination and emergence of glyphosate-resistant hybrid and volunteer corn. The results indicated that response of hybrid and volunteer corn to majority of the variables tested was similar, suggesting that volunteer corn can germinate and emerge in a wide range of climatic conditions. Majority of growers control volunteer corn when it is visible above the soybean canopy, but this can results in early season competition with soybean. The third objective was to evaluate the impact of different densities of glyphosate-resistant volunteer corn at different control timings, and late season volunteer corn emergence on soybean yields. Late season volunteer corn emergence had no significant effect on soybean yield. Yield did not decrease with all volunteer corn densities, except with the highest density (10,000 plants and 500 clumps ha^-1) at all control timings. Soybean growers are looking for alternative herbicides, such …

Root Growth Of Two Perennial Grass Types And Musk Thistle (Carduus Nutans) In Temperate Grasslands Of North America, Chengchou Han, Stephen L. Young

West Central Research and Extension Center, North Platte

Root architecture of prairie grasslands, which depends on plant phenology and edaphic conditions, strongly influences susceptibility to invasion by nonindigenous plant species. Field studies were conducted to compare in situ root growth patterns of warm-season (WS) and cool-season (CS) perennial grasses and musk thistle during a 2-yr period that included a drought in the second year. In 2 yr, CS grasses had the highest amount of roots (1,296 m roots m^–2 [395 ft roots ft^–2]) across shallow (0 to 28 cm [0 to 11 in.]), medium (28 to 56 cm), and deep (56 to 98 cm) depths …

Glyphosate Resistant Weeds - Beat Them Before They Beat You, Sally Peltzer

Grain and other field crops published reports

Herbicide resistance develops if the weeds exist in the population and set fertile seed. Being vigilant, keeping weed populations low and stopping seed set is the best way to prevent glyphosate resistance development:

• know the herbicide use history of each paddock. If glyphosate has been the dominant knockdown and spray-topping product used, it's time to change
• conduct herbicide resistance testing to determine what herbicides are effective on key weeds
• aim for maximum control
• establish a more diverse rotation to increase the number of control tactics available
• use non-herbicide control tactics at every opportunity
• always monitor the success of each control …

Sorghum Transformation: Overview And Utility, Tejinder Kumar, Arlene Howe, Shirley Sato, Ismail M. Dweikat, Tom E. Clemente

Department of Agronomy and Horticulture: Faculty Publications

Over the past decade genomics resources available for sorghum have rapidly expanded (Paterson Int J Plant Genomics 2008:6, 2008), these resources, coupled with the recent completion of the genome sequence which is relatively small in size (730 Mb) (Paterson et al. Nature 457:551–556, 2009) makes sorghum a rather attractive species to study. Moreover, the USDA germplasm system maintains 42,614 accessions, of which more than 800 exotic landraces have been converted to day length-insensitive lines to facilitate their use in breeding programs. In addition, a set of EMS mutation stocks developed by the USDA Plant Stress and Germplasm Development Unit in …

Refining Thresholds In Coupled Fire–Vegetation Models To Improve Management Of Encroaching Woody Plants In Grasslands, Dirac L. Twidwell Jr, Samuel D. Fuhlendorf, Charles A. Taylor Jr, William E. Rogers

Department of Agronomy and Horticulture: Faculty Publications

1. Restoration priorities are typically established without quantitative information on how to overcome the thresholds that preclude successful restoration of desirable ecosystem properties and services. We seek to demonstrate that quantifying ecological thresholds and incorporating them into management-oriented frameworks provide a more comprehensive perspective on how the threshold concept can be applied to achieve restoration goals.

2. As an example, restoration actions have been largely unsuccessful when based on prevailing ecological knowledge of fire-based thresholds in nonresprouting Juniperus woodland. We build on previous threshold-based research and link well-established models from applied fire physics with a widely applied ecological positive feedback …

Barrow Island Ute Guide - Non-Indigenous Invertebrates, Frogs, Reptiles & Weeds, Mike Grimm, Kristofer Collett, Jessica Harrison, Peter Davis, Marc Widmer, Andras Szito, Rob Emery, Peter Mangano, John Botha, David Robinson, Brad Maryan

Biosecurity published reports

Barrow Island, the second largest island in Western Australia, is a Class A Nature Reserve and home to a variety of rare and endangered fauna and flora, some of which occur nowhere else. To protect fauna and flora it is essential workers and visitors to the island are aware of the risks that a non-indigenous species (NIS) poses to the ecological balance of Barrow Island.

Workers and visitors to Barrow Island need to be aware and keep their eyes open for any unusual fauna and flora that might be in accommodation units, recreation areas or the work place. Reports from …

Understanding The Biology, Inheritance And Mechanism Of Resistance Of 2,4-D Resistant Waterhemp (Amaranthus Tuberculatus): Research Proposal, Roberto Crespo

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

Waterhemp is a very well adapted summer annual weed to the U.S. Corn Belt region. Auxinic herbicides such as 2,4-D constitute effective and widely used herbicides to control waterhemp and other broadleaf species in cereal crops and turf grasses. Recently, Bernards et al. (2012) have reported a Nebraska waterhemp biotype has evolved resistant to 2,4-D. This finding represents the sixth mode-of action herbicide group to which waterhemp has evolved resistance to. Several attributes may have contributed to make waterhemp a very successful weed and prone to evolve to herbicide resistant: a high genetic variability, aggressive growth habits and high fecundity. …

Superweeds And Suspect Seeds: Does The Genetically-Engineered Crop Deregulation Process Put American Agriculture At Risk, Margaret Sova Mccabe

Law Faculty Scholarship

The federal government’s regulatory approach to genetically engineered (GE) crops, known as “The Framework”, is now twenty-five years old. Despite two and half decades of a consistent regulatory regime, GE crop and food regulation remains controversial. This article suggests that regulatory science and its tenets of independence, transparency, and public science should guide reforms of The Framework so that it is an efficient and reliable regulatory system. The article has four parts: 1) it provides a brief overview of the history of GE crop regulation; 2)it describes the key attributes of The Framework and related regulatory documents, with particular focus …

Western Australia's Biosecurity, Department Of Agriculture And Food, Western Australia, Department Of Environment And Conservation, Western Australia, Department Of Fisheries, Western Australia, Forest Products Commission, Western Australia

Biosecurity published reports

Biosecurity is the protection of the economy, environment and human health from the negative impacts of pests, weeds and diseases, including the management of invasive species if they become established (definition adopted by AusBIOSEC).

This requires steps to prevent the entry of harmful organisms, as well as the timely and efficient management of them if they do enter.

Biosecurity threats range from catastrophic diseases such as Foot and Mouth Disease, which causes rapid and widespread animal deaths, to more subtle and slower spreading problems such as invasive weeds, mussels that foul vessel hulls and fungus-induced dieback disease of trees. These …

Common Waterhemp Growth And Fecundity As Influenced By Emergence Date And Competing Crop, E. Uscanga-Mortera, S. Clay, F. Forcella, J. Gunsolus

Agronomy, Horticulture and Plant Science Faculty Publications

Common waterhemp (Amarathus rudis Sauer) is a frequent weed in glyphosate-resistant (GR) crops in the midwestern USA due, in part, to the delayed emergence of its seedlings. Variable waterhemp emergence was simulated by transplanting seedlings into both corn (Zea mays L.) and soybean [Glycine max (L.) Merr.] and bare plot areas at differing crop growth stages during two growing seasons in western Minnesota. Growth and fecundity were measured. As expected, late planted weeds produced little dry matter and few seeds, and competition from corn or soybean reduced waterhemp dry weight and fecundity by 90% compared with isolated plants. Interestingly, common …

Common Seasonal Pests : Your Handy Guide To Prevent The Spread Of Animal And Plant Pests, Diseases And Weeds., Department Of Agriculture And Food, Wa

Bulletins 4000 -

This bulletin provides information on quarantine, common pests and common household pests in Western Australia. Details include identification, damage caused, seasonal occurance of pest, action to take, control measures, and where to seek advice.

Green Mulch From Invasives Offers Many Benefits, W. John Hayden

Biology Faculty Publications

For the past several years, I’ve been clipping leafy branchlets of autumn olive for direct use as green mulch in my vegetable garden. In essence, I clip the shoots into segments ranging from 4 to 10 inches long, gathering the freshly chopped mulch into a wheelbarrow. I like to emphasize the youngest and leafiest stems, but since I am also interested in reducing the exotic plant’s biomass, I also clip woody stems up to a half inch in diameter. I then place the coarse mulch, leaves, young stems, and chopped woody branchlets, around my vegetable plants. I install the fresh …

The Land Is In Your Hands : A Practical Guide For Owners Of Small Rural Landholdings In Western Australia, Department Of Agriculture And Food, Wa

Bulletins 4000 -

This Bulletin discusses various aspects of managing a small farm or property in Western Australia, including soil and land care, vegetation and plant control on farm holdings, water resource management, biosecurity, plant, animal and insect pest control and livestock management.

Be Creative When Controlling Invasive Plant Species, W. John Hayden

Biology Faculty Publications

We are often told that every cloud has a silver lining, but when it comes to invasive exotic species, it seems that the proverbial silver lining is vanishingly thin. Invasives like kudzu, Japanese honeysuckle, tree-of-heaven, and oh-so-many others, seem ubiquitous, crowding out native plants and altering all manner of ecological interactions. Like a rock tossed in a placid pond, the negative impact of an exotic species can ripple throughout the entire ecological community. Further, populations of invasive plants can be so large and so extensive across the countryside that complete eradication is simply out of the question. The genie is …

Blue Mustard Control, Drew J. Lyon, Robert N. Klein, Robert G. Wilson

University of Nebraska-Lincoln Extension: Historical Materials

Blue mustard is a troublesome weed in winter wheat and alfalfa in central and western Nebraska. This NebGuide discusses methods of control.

Blue mustard [Chorispora tenella (Pallas) D.C.] was introduced into the United States from Siberia in 1929 and was first reported in Lewiston, Idaho. It was identified in Keith County, Nebraska in 1953. Blue mustard is a winter annual weed, with seed germinating in late summer and fall. The plant overwinters as a rosette. The flower stalk usually elongates, a process known as bolting, in March. With mild February weather, bolting may occur in early March. Cold weather …

A Guide For Skeleton Weed Management And Control, Department Of Agriculture And Food, Western Australia

Bulletins 4000 -

Assisting Western Australian landholders to eradicate skeleton weed and to prevent its further spread within the State

Sheep Updates 2005 - Part 6, Sarah Pugh, Giles Glasson, Ed Barrett-Lennard, Hayley Norman, Matt Wilmot, Meir Altman, Kelly Pearce, Sally Phelan, David Masters, Nadine Eva, Brad Wooldridge, Stephen Gherardi, Lucy Anderton, Gonzalo Mata, P. Sanford, J Young, Tim Wiley, Richard Quinlan, Chris Oldham, Mike Hyder, Mandy Curnow, Samantha Giles, Andrew Thompson

Sheep Updates

This session covers seven papers from different authors:

PASTURES/GRAZING

1. New annual pastures - quality and quantity for fodder conservation?, Sarah Pugh and Giles Glasson, Department of Agriculture Western Australia

2. Saltland Pastures: Dispelling some Myths, Ed Barrett-Lennard^1,3, Hayley Norman^2,3, Matt Wilmat^2,3, Meir Altman,³, Kelly Pearce^2,3, Sally Phelan⁴, David Masters^2,3, ^1. Department of Agriculture, Western Australia, ² CSIRO Livestock Industries, Floreat, WA, ³. CRC for Plant-based Management of Dryland Salinity ⁴. Saltland Pastures Association

3. Pastures: Putting profit back into sandplain, Nadine Eva, Department …

Integrated Weed Management Plan For The Lower Las Vegas Wash, Elizabeth Bickmore

Publications (WR)

The Las Vegas Wash (Wash) is the primary drainage for the metropolitan Las Vegas Valley, eventually finding its way into the Colorado River watershed system. Pursuant to the recommendations of the Water Quality Citizens Advisory Committee, the Las Vegas Wash Coordination Committee (LVWCC) was formed in 1998 to develop a comprehensive plan for the long-term stabilization and management of the Wash. Consisting of representatives from 28 government agencies, businesses, environmental groups and citizens, the LVWCC formulated the Las Vegas Wash Comprehensive Adaptive Management Plan (CAMP) and designated the Southern Nevada Water Authority (SNWA) as the lead agency for the implementation …

Crop Updates 2002 - Weeds, Vanessa Stewart, Peter Newman, Glenn Adam, Andrew Blake, Natalie Lauritsen, Sally Peltzer, Paul Matson, Nerys Wilkins, David Minkey, Glen Riethmuller, Tim Cusack, Kathryn Steadman, Pippa Michael, Paul Blackwell, Dave Brindal, Michael Walsh, Wayne Parker, Clinton Revell, Giles Glasson, Dean Thomas, Alister Draper, Bill Roy, Marta Monjardin, David Pannell, Stephen Powles, Robert Barrett-Lennard, Martin Bent, Paul Neve, Art Diggle, Patrick Smith, Mechelle Owen, Abul Hashem, Christopher Preston, Tracey Gillam, Rick Llewellyn, Richard Quinlan, Aik Cheam, Siew Lee, Mike Clarke, David Nicholson, Harmoohinder S. Dhammu, Terry Piper, Chad Sayer, Ian Rose, Andrew Blake, Jerome Critch, Gordon R. Cumming, Sam Taylor, John Moore, Rosyln Jettner, Stuart Bee, Lionel Martin, Keith Devenish, Felicity Flugge, Amir Abadi, Duncan Peter, Stuart Mcalpine

Crop Updates

This session covers fifty eight papers from different authors:

1. INTRODUCTION Vanessa Stewart, DEPARTMENT OF AGRICULTURE

INTEGRATED WEED MANAGEMENT

IWM system studies / demonstration sites

2. Major outcomes from IWM demonstration sites, Alexandra Douglas Department of Agriculture

3. Integrated weed management: Katanning, Alexandra Douglas Department of Agriculture

4. Integrated weed management: Merredin, Vanessa Stewart Department of Agriculture

5. Long term resistance site: Get ryegrass numbers low and keep them low! Peter Newman and Glen Adams Department of Agriculture

6. Using pastures to manage ryegrass populations, Andrew Blake and Natalie Lauritsen Department of Agriculture

Weed biology and competition

7. …

Declared Plant Control Handbook Recommendations For The Control Of Declared Plants In Western Australia, John R. Peirce, Rachael A. Pratt

Biosecurity published reports

Sixth Edition.

Reviewed October 2005.

Plants may be "declared" by the Agriculture Protection Board under the Agriculture and Related Resources Protection Act 1976.If a plant is declared, all landholders are obliged to control that plant on their properties. Declarations specifies a category, or categories, for each plant according to the control strategies or objectives which the Agriculture Protection Board believes are appropriate in a particular place.

Among the factors considered in categorising declared plants are:

* the impact of the plant on individuals, agricultural production and the community in general,

* whether it is already established in the area, and …

Agriculture Western Australia's Great Southern Agricultural Research Institute Katanning, Agriculture Western Australia

Natural resources published reports

Agriculture Western Australia's Great Southern Agricultural Research Institute has been established as a centre of excellence for research, development and extension into sustainable farming systems The. agency has a long association with the town of Katanning dating back to 1925 when the agency provided a general agricultural advisor.

The new Institute is strategically located in the heart of key sheep and cropping production areas with significant growth potential.

Its role is to stimulate the contribution of ideas from individuals, groups and organisations with an interest in research, development and extension relating to innovative, profitable and sustainable animal and cropping based …

Basic Biotechnology, Jennifer Flak, Julie Albrecht

Plant and Soil Sciences eLibrary

An introduction to traditional cross-breeding and genetic engineering of plants, and to biotechnology.

Objectives - Basic Biotechnology

After completing Nutrition Basic Biotechnology, participants should be able to:

• Describe one similarity between traditional cross-breeding and genetic engineering of plants.
• Give two limitations that are encountered with traditional cross-breeding of plants.
• Explain why genetic engineering is not limited in the same way as traditional cross-breeding.
• Define biotechnology in broad terms.
• List three plant applications of biotechnology.
• List the three areas of nutritional profiles that have been improved with biotechnology.

Modules:

• Lesson home
• Objectives - Basic Biotechnology
• Historical Uses of Biotechnology
• Basic Understanding …

Native Vegetation Handbook For The Shire Of Kondinin, Bec Ryan

Bulletins 4000 -

This booklet provides land managers with information relating to the natural resources of the Shire of Kondinin, including the landscape, geology, soils, drainage systems, native flora and fauna. Information about native flora and vegetation has been drawn from a variety of sources, including surveys that estimated the distribution of plant communities prior to clearing, recent surveys of privately owned remnants, herbarium collections, surveys of nature reserves and roadside surveys. Some of the problems relating to the management of these resources within the shire and ideas or community initiatives to solve these problems are also discussed. It is hoped that this …

Native Vegetation Handbook For The Shire Of Lake Grace, Bec Ryan

Bulletins 4000 -

This handbook provides land managers with information relating to the natural resources of the Shire of Lake Grace, including the landscape, geology, soils, drainage systems, native flora and fauna. Information about native flora and vegetation has been drawn from a variety of sources, including surveys that estimated the distribution of plan communities prior to clearing, recent surveys of privately owned remnants, herbarium collections, surveys of nature reserves and roadside surveys. Some of the problems relating to the management of these resources within the shire and ideas and community initiatives to solve these problems are also discussed. It is hoped that …

Native Vegetation Handbook For The Shire Of Kulin, Bec Ryan

Bulletins 4000 -

This handbook provides land managers with information relating to the natural resources of the Shire of Kulin, including the landscape, geology, soils, drainage systems, native flora and fauna. Information about native flora and vegetation has been drawn from a variety of sources, including surveys that estimated the distribution of plant communities prior to clearing, recent surveys of privately owned remnants, herbarium collections, surveys of nature reserves and roadside surveys. Some of the problems relating to the management of these resources within the Shire and ideas and community initiatives to solve these problems are also discussed. It is hoped that this …