Multi-Tactic Ecological Weed Management In A Changing Climate, 2018 University of Maine
Multi-Tactic Ecological Weed Management In A Changing Climate, Sonja K. Birthisel
Electronic Theses and Dissertations
Climate change is expected to impact weed communities in Maine, and the efficacy of tools and tactics farmers use to manage them. Through seedbank sampling and surveys of Maine organic farms, we identified currently rare weeds that are known to be especially abundant or problematic in warmer areas of the USA and might therefore represent an emerging agronomic risk. Many ecological weed management strategies that focus on depleting the weed seedbank are expected to remain effective in a changing climate, and become increasingly important as efficacy of cultivation and some herbicide applications diminish or become more variable. Through field experiments ...
Synthesis Of Dicamba Glucosides For The Study Of Environmental Dicamba Drift Effects On Soybeans, 2018 University of Arkansas, Fayetteville
Synthesis Of Dicamba Glucosides For The Study Of Environmental Dicamba Drift Effects On Soybeans, Holly Wallace
Theses and Dissertations
The most popular herbicide used for weed control has been glyphosate for many years in the Midwestern United States. Plants have begun to develop a resistance to glyphosate due to over use of the herbicide. This herbicide resistance has pushed farmers to turn to alternative herbicides such as dicamba and 2,4-D. Recently agrochemical companies have developed genetically modified crops that are resistant to herbicides such as dicamba. These modified crops allow farmers to spray their fields with dicamba without fear of crop damage. Farmers of non-genetically modified crops, however, suffer damage and loss of yield from herbicide drift effects ...
Weed Control And Management For Vegetable Soybeans In Arkansas, 2018 University of Arkansas, Fayetteville
Weed Control And Management For Vegetable Soybeans In Arkansas, Seth Bernard Abugho
Theses and Dissertations
Vegetable soybean [Glycine max (L.) Merr.], known as edamame, needs weed management tools. Releasing locally adapted edamame soybean varieties and registering herbicides are necessary for successful production and expanding the edamame industry. This research aimed to 1) identify herbicides labeled for grain soybean for potential use on edamame; 2) evaluate differential tolerance of edamame soybean varieties to selected grain soybean herbicides; and 3) identify a feasible edamame-based crop rotation system. For objective 1, 26 herbicide treatments were tested on AVS-4002 edamame including preplant (PPL), preemergence (PRE) and postemergence (POST) herbicides labeled for grain soybean. Preplant herbicides caused 9 to 28 ...
Soybean Response To Dicamba: Associated Injury Criteria And Development Of A Model To Predict Yield Loss, 2018 Louisiana State University and Agricultural and Mechanical College
Soybean Response To Dicamba: Associated Injury Criteria And Development Of A Model To Predict Yield Loss, Matthew Ryan Foster
LSU Doctoral Dissertations
In research conducted using indeterminate soybean [Glycine max (L.) Merr.], fourteen injury criteria observed following dicamba at 0.6 to 280 g ae ha-1 (1/1000 to ½ of 560 g ha-1 use rate) were rated using a scale of 0= no injury, 1= slight, 2= slight to moderate, 3= moderate, 4= moderate to severe, and 5= severe. Greatest crop injury 15 d after treatment (DAT) was observed following dicamba applied at 0.6 to 4.4 g ha-1 at V3/V4 for upper canopy pale leaf margins (3.8 to 4.2) and at R1/R2 ...
Yardwork: A Biography Of An Urban Place By Daniel Coleman, 2018 University of Calgary
Yardwork: A Biography Of An Urban Place By Daniel Coleman, Vivian M. Hansen
Review of Daniel Coleman's Yardwork: A Biography of an Urban Place.
Genetic Diversity In An Invasive Clonal Plant? A Historical And Contemporary Perspective, 2018 University of New Orleans
Genetic Diversity In An Invasive Clonal Plant? A Historical And Contemporary Perspective, Elliot D. Weidow
University of New Orleans Theses and Dissertations
Introduced populations of Eichhornia crassipes (Pontederiaceae) possess extremely low levels of genetic diversity due to severe bottleneck events and clonal reproduction. While populations elsewhere have been well studied, North American populations of E. crassipes remain understudied. We used Amplified Fragment Length Polymorphism markers to assess genetic diversity and population structure in North American E. crassipes populations. Patterns of diversity over the past fifty years were analyzed using herbarium specimens. Furthermore, we sampled populations across the Gulf Coast of the United States throughout a year to determine contemporary genetic diversity and assess potential seasonal effects. Genetic diversity was found to be ...
Perma/Culture: Imagining Alternatives In An Age Of Crisis By Molly Wallace And David Carruthers, 2018 University of Miami
Perma/Culture: Imagining Alternatives In An Age Of Crisis By Molly Wallace And David Carruthers, Bryant Scott
Review of Molly Wallace and David Carruthers' Perma/Culture: Imagining Alternatives in an Age of Crisis.
Band-Sowing With Hoeing For Weed Management In Organic Grains, 2018 University of Maine
Band-Sowing With Hoeing For Weed Management In Organic Grains, Margaret R. Mccollough
Electronic Theses and Dissertations
Weeds remain the foremost production challenge for organic small grain growers in the Northeastern United States. Instead of sowing crops in narrow, single-line rows, band-sowing with inter-band hoeing is a cropping strategy that could provide superior weed control. In theory, band-sowing suppresses weeds in the intra-band zone by improving the spatial arrangement of the crop from that of typical rows to a more uniform pattern within the planted bands, maximizing interspecific and reducing intraspecific competition. Weeds in the inter-band zone are controlled by cultivating with aggressive sweeps; tine harrowing can target weeds in the intra- and inter-band zones.
Chapter one ...
Evaluation Of Acetochlor And Other Very-Long-Chain Fatty Acid-Inhibiting Herbicides In Arkansas Rice, 2018 University of Arkansas, Fayetteville
Evaluation Of Acetochlor And Other Very-Long-Chain Fatty Acid-Inhibiting Herbicides In Arkansas Rice, Michael E. Fogleman
Theses and Dissertations
The prevalence of herbicide resistance and lack of effective management options for controlling problematic weeds such as barnyardgrass and weedy rice in Arkansas rice production has led to exploration of alternative herbicide sites of action (SOA). Very-long-chain fatty acid (VLCFA)-inhibiting herbicides are not currently labeled for use in U.S. rice production but have been used with success in other row crops and in rice production in Asia. Based on preliminary research, rice tolerance and weed control were evaluated following various application timings and rates of acetochlor and pethoxamid, in addition to several other VLCFA-inhibiting herbicides. Rice tolerance to ...
Mitigating Bioiversity Loss Of Native Plants, 2018 Fordham University
Mitigating Bioiversity Loss Of Native Plants, Jamie Ana Grigonis
Student Theses 2015-Present
Growing up harvesting from my own vegetable garden and going from nursery to nursery with my mother, it has been extremely evident that plant biodiversity is more than just privet along driveways and carnations in window boxes. Plant biodiversity is often overlooked but crucial to having a healthy and thriving environment. Without certain plants, our ecosystems will crumble and this needs to be addressed now while it’s still at a level we can grow from. In my internship I am working alongside the director of the Thain Family Forest at the New York Botanical Gardens in order to get ...
Combinations Of Allelopathic Crop Extracts Reduce Digitaria Spp. And Setaria Faberi Seed Germination, 2018 University of Connecticut Department of Plant Science
Combinations Of Allelopathic Crop Extracts Reduce Digitaria Spp. And Setaria Faberi Seed Germination, Peter Apicella, Karl Guillard
Honors Scholar Theses
Allelopathic cover crops contain compounds that deter other types of plant seeds from germinating or inhibiting established plants’ growth. Sunflower (Helianthus annuus, SF), buckwheat (Fagopyrum esculentum Moench, BW), sorghum-sudangrass (Sorghum × drummondii [Nees ex. Steud.] Millsp. & Chase, SSG), and winter rye (Secale cereale) are all known allelopathic cover crops. However, there is little information about the use of these allelopathic cover crops used together and their combined impact on weed seed germination. Laboratory bioassays were conducted to determine the effect of the aforementioned cover crops alone and in combinations in reducing the germination rate of Digitaria spp. (crabgrass) and Setaria faberi ...
Influence Of Multispecies Interference Of Common Ragweed (Ambrosia Artemisiifolia L.) And Common Waterhemp (Amaranthus Rudis Sauer) On Soybean [Glycine Max (L.) Merr.] Growth And Yield Under Variable Water Supply In Nebraska, 2018 University of Nebraska - Lincoln
Influence Of Multispecies Interference Of Common Ragweed (Ambrosia Artemisiifolia L.) And Common Waterhemp (Amaranthus Rudis Sauer) On Soybean [Glycine Max (L.) Merr.] Growth And Yield Under Variable Water Supply In Nebraska, Koffi Badou Jeremie Kouame
Theses, Dissertations, and Student Research in Agronomy and Horticulture
Common ragweed (Ambrosia artemisiifolia L.) and common waterhemp (Amaranthus rudis Sauer) are two problematic weeds for soybean producers in the United States. Both weeds have evolved resistance to many herbicides, including glyphosate. It is therefore essential to understand how these weeds in mixture impact soybean growth and yield and also how they deplete soil moisture in rainfed and irrigated cropping systems. The objectives of this research were to: (i) understand the influence of variable water supply on soybean yield loss in mixture with ragweed and waterhemp, (ii) quantify the influence of variable water supply on soybean growth in mixture with ...
Non-Target-Site Based Tolerance To Herbicides In Amaranthus Palmeri, 2018 University of Arkansas, Fayetteville
Non-Target-Site Based Tolerance To Herbicides In Amaranthus Palmeri, Reiofeli Algodon Salas-Perez
Theses and Dissertations
Palmer amaranth, one of the most aggressive and damaging broadleaf weeds in the USA, has evolved resistance to multiple herbicide modes of action. The overall objective of this research was to elucidate the mechanisms by which Palmer amaranth adapt to herbicide selection stress. This research aimed (1) to evaluate the efficacy of fomesafen, glufosinate, glyphosate and trifloxysulfuron to Amaranthus populations; (2) identify candidate genes for endowing tolerance to glufosinate; (3) investigate the involvement of non-target-site resistance (NTSR) mechanism in an ALS-resistant population; and (4) to examine the molecular basis of resistance to PPO inhibitors in Palmer amaranth populations from Arkansas ...
Reducing Tillage In Small-Scale Permanent Bed Organic Vegetable Production Systems, 2018 University of Maine
Reducing Tillage In Small-Scale Permanent Bed Organic Vegetable Production Systems, Jeremiah D. Vallotton
Electronic Theses and Dissertations
The response of field-grown vegetable crops to reduced tillage and mulching in permanent beds was evaluated through measuring crop yields, weed pressure, earthworm counts, and soil basal respiration. Two vegetable crops (“Bush Delicata” squash and “Farao” cabbage) were started in April and May of 2016 and 2017 respectively, transplanted in late June, and harvested on 15-Sep-2016 and 25-Aug-2017. Fruit number and weight of squash, and head weight and feeding damage of cabbage were measured. These results suggest that intensive tillage (8” rototill every year) can be successfully reduced to alternating years of shallow (2”) rototilling and a less intensive form ...
Diversity Post-Wildfire Of Vegitabel Understory In Rocky Mountain Ponderosa Pine Woodland And Montane Sagebrush Steppe, Bryce Walker
Carroll College Student Undergraduate Research Festival
In Montana, big sagebrush steppe, montane sagebrush steppe and rocky mountain ponderosa pine woodland take up over 16% of Montana’s 380,832 km2 (16.45%). Studies have shown that habitats dominated by graminoids depend on species abundance and richness to regulate invasion (Tilman 1997). The invasion process can be facilitated by the removal of native perennial species and the accumulation of seed banks of invasive annual grasses (Melgoza et al. 1990). Wildfire can contribute to these factors. A wildfire near Big Saw-Mill Gulch on September 1st 2016 offers an opportunity to compare diversity and richness in burned areas compared ...
Exploring Alternative Giant Salvinia (Salvinia Molesta D.S. Mitchell) Management Strategies, 2018 Louisiana State University and Agricultural and Mechanical College
Exploring Alternative Giant Salvinia (Salvinia Molesta D.S. Mitchell) Management Strategies, Bradley T. Sartain
LSU Doctoral Dissertations
Dense infestations of the free-floating aquatic fern giant salvinia (Salvinia molesta D.S. Mitchell) have been expanding across the southeastern United States for over two decades. Although herbicide programs have provided relief to giant salvinia infested areas, morphology and growth characteristics make management difficult. A series of mesocosm trials were conducted to explore alternative management strategies for giant salvinia. Evaluation of non-registered aquatic herbicides showed that rates of sulfometuron and metsulfuron controlled giant salvinia and provided a 98 to 100% biomass reduction. An outdoor mesocosm trial evaluated potential glyphosate resistance in giant salvinia in select water bodies throughout Louisiana. Differences ...
Determining Growth Characteristics And Control Programs For Nealley's Sprangletop (Leptochloa Nealleyi Vasey), 2018 Louisiana State University
Determining Growth Characteristics And Control Programs For Nealley's Sprangletop (Leptochloa Nealleyi Vasey), Trace Buck
LSU Master's Theses
Research was conducted at the LSU AgCenter Dean Lee Research and Extension center near Alexandria, La in 2016 and 2017 to evaluate the growth characteristics and control of Nealley’s sprangletop. Nealley’s sprangletop is a relatively new weed with little research available to understand its growth habit and effective control strategies.
Nealley’s sprangletop undergoes a more drastic height increase of 212 to 742 mm, 4 to 6 WAE than Amazon sprangletop 377 to 612 mm in the same time frame. Averaged across harvest interval tiller and leaf number of Nealley’s sprangletop was approximately 50 and 40 ...
Roadside Integrated Vegetation Management Bmps: Right Tool For The Right Job, 2018 Davey Resource Group, Inc.
Roadside Integrated Vegetation Management Bmps: Right Tool For The Right Job, Cheryl Daniels, Davey Resource Group, Inc.
Purdue Road School
Based on a 3-year ODOT IVM research project, lessons learned and techniques for innovative and adaptive IVM for diverse midwestern landscapes will be presented that can increase Indiana DOTs’ efficiency and cost-effectiveness and simultaneously improve worker safety, foster safe highway use, improve roadside aesthetics, and promote environmental stewardship.
Gene Flow From Single And Stacked Herbicide-Resistant Rice (Oryza Sativa): Modeling Occurrence Of Multiple Herbicide-Resistant Weedy Rice, 2018 University of Nebraska‐Lincoln
Gene Flow From Single And Stacked Herbicide-Resistant Rice (Oryza Sativa): Modeling Occurrence Of Multiple Herbicide-Resistant Weedy Rice, Joseph Dauer, Andrew Hulting, Dale Carlson, Luke Mankin, John Harden, Carol Mallory-Smith
Papers in Natural Resources
Background: Provisia™ rice (PV), a non-genetically engineered (GE) quizalofop-resistant rice, will provide growers with an additional option for weed management to use in conjunction with Clearfield® rice (CL) production. Modeling compared the impact of stacking resistance traits versus single traits in rice on introgression of the resistance trait to weedy rice (also called red rice). Common weed management practices were applied to 2-, 3- and 4-year crop rotations, and resistant and multiple-resistant weedy rice seeds, seedlings and mature plants were tracked for 15 years.
Results: Two-year crop rotations resulted in resistant weedy rice after 2 years with abundant populations (exceeding ...
Comparison Of Soil-Applied And Postemergence Herbicides With Multiple Sites Of Herbicidal Activity On Two Populations Of Herbicide-Resistant Palmer Amaranth In Kentucky, Nicholas J. Fleitz
Theses and Dissertations--Plant and Soil Sciences
With the introduction of herbicide resistant Palmer amaranth into Kentucky during the past 10 years there has been an increasing concern for effective control measures in grain production. Field trials were performed in 2016 and 2017 near Barlow and Paris, KY to determine efficacy of chemical control programs targeting herbicide resistant Palmer amaranth. Percent visual control, effects on plant density and plant height were measured in 2016 to determine treatment effectiveness. Treatments containing four different sites of herbicide activity achieved an average of 98% control. Treatments containing only 3, 2 or 1 site of activity only achieved 64%, 45% and ...