Download or read book Evaluating Cover Crops and Herbicides for Horseweed and Palmer Amaranth Management written by Larry Joe Rains (III) and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Horseweed and Palmer amaranth are common weeds in Kansas that compete against many row crops. Horseweed can emerge in different seasons depending on the year. Palmer amaranth emerges from spring throughout the summer months and has a rapid growth rate with higher temperatures. Three separate studies were conducted near Manhattan, KS from 2016 to 2018 to determine (1) horseweed control in no-till soybean with cover crops and herbicide programs with and without residual activity (2) emergence timing in KS of eight horseweed populations collected from MO, IL, KS, and KY, and (3) Palmer amaranth control in response to three Protoporphyrinogen Oxidase (PPO) inhibitors applied every three days once Palmer amaranth plants reached 2.5 cm tall. Cereal rye reduced weeds biomass by 78% and weed density by 75% by 8 weeks after cover crop seeding in the fall. At cover crop termination two weeks prior to soybean drilling. Cereal rye reduced horseweed biomass more than herbicide treatments, but after termination weed control was similar across treatments. Soybean yields were greater with herbicide treatments in year one, but there were no differences in soybean yields among cover crop and herbicide treatments in the second year. Emergence of all eight horseweed populations occurred at the same time. Most horseweed emergence occurred in the spring in the first year, while all horseweed populations emerged in the fall in the second year. Environmental conditions were driving factors for horseweed emergence, but horseweed seed source did not influence emergence timing. All PPO-inhibitor herbicides controlled Palmer amaranth at similar levels within an application timing. PPO-inhibitor herbicides need to be applied within three days after Palmer amaranth plants reach 2.5 cm tall to achieve greater than 90% control.

Download or read book Integrating Cover Crops and Herbicides for Horseweed and Palmer Amaranth Management in No till Soybean written by Chelsea Marie McCall and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Palmer amaranth and horseweed are problematic weeds in no-till soybeans in Kansas. Integrating cover crops and herbicide programs could suppress weed populations. To determine the emergence pattern and survival of horseweed, a study was conducted across six locations in eastern KS in 2014-2015 and 2015-2016. Horseweed seedlings and leaf number per seedling were recorded at two-week intervals. Cumulative GDDs required to reach 50% horseweed emergence increased from north to south. Horseweed survival ranged from 4 to 90%, and majority of horseweed emerged in the fall. Field studies were conducted to determine effects of cover crops and herbicide programs on Palmer amaranth near Manhattan, KS in 2014-2015 and 2015-2016. Five cover crop treatments included no cover, fall-sown winter wheat, spring-sown oat, pea, and mixture of oat and pea. Cover crops were terminated in May with glyphosate and 2,4-D alone or with residual herbicides of flumioxazin and pyroxasulfone. By 10 weeks after termination in 2014-2015, Palmer amaranth biomass and density, averaged across cover crops. was 95 and 69% less with residual herbicides than without, respectively, and Palmer amaranth biomass was 98% less in winter wheat and 91% less in spring oat, averaged across termination methods, compared to no cover. Time to 50% Palmer amaranth emergence was delayed with winter wheat, spring oat, and spring oat/pea mix without residual herbicide. Soybean yields were greater with residual herbicide and greater with winter wheat or spring oat cover crop in 2014-2015. A field study was conducted to determine suppression effects of cover crop and herbicide programs on horseweed and Palmer amaranth near Manhattan, KS in 2015-2016. Three fall treatments included fall-sown rye, a residual herbicide tank mix of glyphosate, dicamba, chlorimuron-ethyl, tribenuron-methyl, and AMS, and no fall application. Four spring treatments included no spring application or three herbicide tank mixes: glyphosate, dicamba, and AMS alone or with flumioxazin and pyroxasulfone as early preplant, or as split applied with 2/3 preplant and 1/3 at soybean planting. Similar levels of horseweed suppression were observed when some control measure was used in fall or spring. Fall rye completely suppressed horseweed while the fall herbicide suppressed biomass by 93% and density by 86% compared to no fall application. Palmer amaranth suppression was observed when a spring herbicide application was used. In rye, total weed biomass was reduced by 97% or more across all spring treatments. Total weed biomass was reduced with a spring herbicide was used. Soybean yields were least when no herbicide treatment was used in the spring. An integrated program of fall cover crops or herbicide applications together with spring herbicide applications maintained soybean yields.

Download or read book Integration and Management of Winter annual Cover Crops and Herbicides to Control Glyphosate resistant Palmer Amaranth Amaranthus Palmeri S Wats written by Matthew Scott Wiggins and published by . This book was released on 2014 with total page 133 pages. Available in PDF, EPUB and Kindle. Book excerpt: The main objective of this research was to evaluate the integration of high residue winter-annual cover crops with herbicides, both preemergence and postemergence, to control glyphosate-resistant Palmer amaranth. The results of these trials indicated that winter-annual cover crops improved early-season weed suppression. However, cover crops alone or as part of an integrated weed management system including only preemergence or only postemergence herbicides was not sufficient to control of glyphosate-resistant Palmer amaranth. Therefore, winter-annual cover crops should be used in conjunction with existing weed control tactics to achieve adequate glyphosate-resistant Palmer amaranth control, where applicable.

Download or read book Integrating a Cereal Rye Cover Crop and Soybean Row Width With Herbicides to Manage Palmer Amaranth in Michigan written by Kelsey Marie Rogers and published by . This book was released on 2017 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Characterization and Management of PPO and Glyphosate Resistant Palmer Amaranth written by Drake Copeland and published by . This book was released on 2018 with total page 147 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research was conducted from the fall of 2016 to the fall of 2018 to characterize and manage PPO- and glyphosate-resistant Palmer amaranth (Amaranthus palmeri S. Wats). Studies included a multi-county survey to determine the prevalence of PPO-resistant Palmer amaranth biotypes and the PPX2 mutations that confer PPO resistance, an in-field evaluation of control of PPO-resistant and PPO-susceptible Palmer amaranth populations with herbicide treatments applied at either sunrise or midday, and field studies that evaluated cover crop termination for control of Palmer amaranth in Roundup Ready Xtend® and Liberty Link® soybean systems [(Glycine max (L.) Merr.]. Results from this research indicate that PPO-resistant Palmer amaranth infests roughly 80% of west Tennessee fields, at least two herbicides with different, effective sites of action should be applied timely for POST herbicidal control of PPO-resistant Palmer amaranth, and that delaying cover crop termination in both Roundup Ready Xtend® and Liberty Link® soybeans can effectively reduce in-season POST applications and maximize Palmer amaranth control if the correct residual herbicide is included at planting timing.

Download or read book Ecological Management of Agricultural Weeds written by Matt Liebman and published by Cambridge University Press. This book was released on 2001-07-19 with total page 546 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents principles and practices for ecologically based weed management in a wide range of temperate and tropical farming systems. Special attention is given to the evolutionary challenges that weeds pose and the roles that farmers can play in the development of new weed-management strategies.

Download or read book Utilizing Cover Crops to Improve Sustainability of Conventional Weed Management Programs written by Garret Brown Montgomery and published by . This book was released on 2016 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Research was conducted from the fall of 2014 to the fall of 2016 to evaluate the optimal utilization of cover crops for weed control in no-till environments. Studies included a corn (Zea mays L.) termination timing study to evaluation different termination intervals of cereal rye (Cereal rye L.), hairy vetch (Vicia villosa Roth.), and a combination of cereal rye and hairy vetch cover crops on corn growth and development, an evaluation of a roller crimper for cover crop termination prior to corn study, an evaluation of a roller crimper for cover crop termination prior to soybeans [Glycine max (L.) Merr.], an evaluation of glyphosate + dicamba tolerant (GDT) soybean utilization in a cover cropping system, and a study to evaluate the effects of fall applied herbicides on four cover crop species from controlling Italian ryegrass (Lolium perenne ssp. multiflorum). Results from this research indicate that a cover crop termination interval prior to corn planting can influence corn growth, development, and yield, a roller crimper is not currently a viable tool for cover crop termination prior to planting corn, a roller crimper can be effectively used for cover crop termination prior to soybeans, GDT soybeans can be readily utilized into a cover cropping system, and that fall applied herbicides can be used with cover crops and aid in controlling Italian ryegrass.

Download or read book Response of Weeds to the Intensification of Kansas No Till Crop Rotations with Cover Cropping written by Justin Scott Petrosino and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: No-till producers can manage weeds by including cover crops during the fallow phase as part of an integrated weed management plan. Field experiments were conducted between 2007 and 2009 to quantify the influence of cover crops on weed emergence, biomass accumulation, and seed production. Field experiments were established near Garden City, KS with winter wheat or fallow as main plots and cover crop treatments as subplots including five spring- and five fall-sown individual or mixtures of crop species and a no-cover chemical fallow. Separate1-m2 quadrats were seeded with kochia or downy brome at 500 seed/m2. Kochia density was reduced by 75% and biomass reduced by 88% in fall-sown cover crops compared to chemical fallow across growing seasons. Spring-sown cover crop mixtures reduced kochia biomass in 2009 when kochia emergence was delayed. Downy brome biomass decreased exponentially as cover crop biomass increased. A second field experiment was established near Manhattan, KS with soybean, winter wheat, or grain sorghum phases of the rotation as main plots and six cover crop treatments as subplots sown after winter wheat harvest. Paired Palmer amaranth 1-m2 quadrats were seeded with 500 seed/m2 in each cover crop subplot. One quadrat was protected from any herbicide application made to the cover crop or to the grain sorghum. Combining burndown application with high biomass-producing cover crops reduced Palmer amaranth emergence and biomass. Influence of cover crop presence reduced early season Palmer amaranth emergence in the subsequent grain sorghum phase. Optimal seeding rate of forage soybean sown in winter wheat stubble and its impact on Palmer amaranth and downy brome emergence and growth were evaluated in field studies established near Manhattan and Hesston, KS in 2008 and 2009. Soybean was no-till drilled after wheat harvest at five rates ranging from 100,000 to 600,000 seeds/ha. A no-cover chemical fallow treatment was included. Separate 0.5-m2 quadrats were seeded with Palmer amaranth at 100 seed/0.5 m2 or with downy brome at 250 seed/0.5 m2. Three termination methods evaluated were killing frost, glyphosate application, or crop rolling. Palmer amaranth density was not affected by treatments but biomass decreased as soybean seeding rate and crop biomass increased. Downy brome emergence was less with rolled or sprayed termination methods in one site year as timing of termination was optimal. High biomass producing cover crops sown during the fallow phase of a crop rotation reduced weed emergence, density, and biomass accumulation. Cover crops can be part of an integrated weed management plan in Kansas.

Download or read book Horseweed Management with Shading and Cover Crops and the Tolerance of Two Horseweed Growth Types to Glyphosate written by Justine Lynn Fisher and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Field experiments were conducted to evaluate if fall-planted cereal rye in combination with narrow row soybean improved glyphosate-resistant (GR) horseweed management. At the time of a postemergence herbicide application (POST), horseweed biomass was 71 to 90% lower when soybean was planted into cereal rye, regardless of termination time, compared with no cover across all row widths. Planting green or narrow row soybean suppressed horseweed through soybean harvest and integrating an effective POST herbicide improved control. Additional field experiments found that in the absence of an effective POST herbicide, horseweed biomass was 42 and 81% lower by planting green or applying a residual herbicide compared with no cover, respectively, at soybean harvest. Similarly, planting soybean in 19 cm rows reduced horseweed biomass compared with 38 and 76 cm rows. In the greenhouse, shade levels from 35 to 92% reduced rosette and upright horseweed biomass 31 to 99% compared with the upright-type grown under 0% shade. Greater reductions occurred under 69 and 92% shade. Differences in glyphosate sensitivity between the rosette and upright horseweed growth types were not due to absorption, translocation, or total glyphosate retention; however, glyphosate retention was 21 and 18% lower on a per weight and area basis for the upright growth type. This diluted concentration may contribute to increased glyphosate tolerance found in the upright growth type. However, other factors such as differences in EPSPS gene expression may also help explain differential sensitivity if a target-mutation is discovered. This research provides growers strategies for managing horseweed and insight into potential growth type differences.

Download or read book Integrating Cover Crops and Herbicides for Horseweed Conyza Canadensis L Cronq Management Prior to Soybean Glycine Max L Merr written by Austin Sherman and published by . This book was released on 2019 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Herbicide Resistant Palmer Amaranth Amaranthus Palmeri S Wats in the United States Mechanisms of Resistance Impact and Management written by Parminder S. Chahal and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Palmer amaranth, a dioecious summer annual species, is one of the most troublesome weeds in the agronomic crop production systems in the United States. In the last two decades, continuous reliance on herbicide(s) with the same mode of action as the sole weed management strategy has resulted in the evolution of herbicide-resistant (HR) weeds, including Palmer amaranth. By 2015, Palmer amaranth biotypes had been confirmed resistant to acetolactate synthase (ALS)-inhibitors, dinitroanilines, glyphosate, hydroxyphenylpyruvate dioxygenase (HPPD)-inhibitors, and triazine herbicides in some parts of the United States along with multiple HR biotypes. Mechanisms of herbicide-resistance in Palmer amaranth are discussed in this chapter. Preplant herbicide options including glufosinate, 2,4-D, and dicamba provide excellent Palmer amaranth control; however, their application is limited before planting crops, which is often not possible due to unfavorable weather conditions. Agricultural biotechnology companies are developing new multiple HR crops that will allow the post-emergence application of respective herbicides for management of HR weeds, including Palmer amaranth. For the effective in-crop management of Palmer amaranth, and to reduce the potential for the evolution of other HR weeds, growers should apply herbicides with different modes of action in tank-mixture and should also incorporate cultural practices including inversion tillage and cover crops along with herbicide programs.

Download or read book Management of Glyphosate resistant Palmer Amaranth amaranth Palmeri S Watson in Dicamba glyphosate resistant Soybean written by Shawn Thomas McDonald and published by . This book was released on 2021 with total page 108 pages. Available in PDF, EPUB and Kindle. Book excerpt: While not a historically problematic weed in Nebraska, Palmer amaranth has become increasingly problematic in many agronomic cropping systems. Throughout the state, several cohorts of Palmer amaranth have been found resistant to several different sites of action. Of major concern is a population found resistant to glyphosate the most common post-emergence herbicide in Nebraska. As chemical control methods are the most common forms of weed control throughout the state methods alternatives or enhancements are highly desired. Two field experiments were conducted in 2018 and 2019 at a grower's field near Carleton, Nebraska with the objectives to evaluate the effects of row spacing and herbicide programs and separately analyze the effect of overlapping residual herbicides on control of glyphosate-resistant (GR) Palmer amaranth, gross profit margin, and benefit-cost ratios of these herbicide programs. Evaluation of the effect on row spacing found no significant effect of narrowing row spacing on control, density, or biomass reduction of GR Palmer amaranth across all herbicide programs. Herbicide program had a higher impact on GR Palmer amaranth control with all PRE fb EPOST except dicamba + chlorimuron/flumioxazin followed by dicamba and all PRE fb EPOST+RH providing greater than 85% control from 14 d after EPOST (DAEPOST) to 36 DAEPOST. Evaluation of overlapping residual herbicides on management of GR Palmer amaranth found that flumioxazin/pyroxasulfone/metribuzin provided 78% to 82% control from 14 DAEPOST to 70 DAEPOST in 2018 and 94% to 98% in 2019. Addition of dicamba + acetochlor EPOST to flumioxazin/pyroxasulfone/metribuzin provided 83% to 96% from 14 DAEPOST to 70 DAEPOST in 2018 and 99% in 2019. As the adoption of new application technologies, herbicide-resistant crops, and alternative weed control methods change with the times, surveys provide insight into changes in weed dynamics and crop production over time. Conducting multiple surveys over the course of several years provides a vital framework in developing future research and extension outreach. During the winter of 2019-2020, a survey of Nebraska stakeholders was carried to quantify crop production, weed control, and management practices throughout the state. In order of importance, Palmer amaranth, horseweed, common waterhemp, kochia, and giant ragweed were ranked the most problematic weeds statewide. Based on survey responses, 27% of respondents, cited integrated weed management systems as the primary concern for future research and extension outreach for the state of Nebraska.

Download or read book Herbicide Resistance in Weeds Early Detection Mechanisms Dispersal New Insights and Management Issues written by Ilias Travlos and published by Frontiers Media SA. This book was released on 2020-10-28 with total page 329 pages. Available in PDF, EPUB and Kindle. Book excerpt: This eBook is a collection of articles from a Frontiers Research Topic. Frontiers Research Topics are very popular trademarks of the Frontiers Journals Series: they are collections of at least ten articles, all centered on a particular subject. With their unique mix of varied contributions from Original Research to Review Articles, Frontiers Research Topics unify the most influential researchers, the latest key findings and historical advances in a hot research area! Find out more on how to host your own Frontiers Research Topic or contribute to one as an author by contacting the Frontiers Editorial Office: frontiersin.org/about/contact.

Download or read book Evaluating Cover Crops to Determine the Best Management Practice for the Suppression of Tall Waterhemp and Italian Ryegrass written by Samuel R. Reeves and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: To combat herbicide resistance among weeds, non-herbicide methods of control, such as cover crops, are becoming widely adapted. Experiments were conducted to determine how to effectively establish and manage cover crops in order to suppress tall waterhemp and Italian ryegrass and to assess their overall impact on soybean growth and yield. Various cover crop establishment methods were evaluated, and it was determined that interseeding at the R7 growth stage of soybean was the least effective method for proper cover crop establishment. Biomass data demonstrated that interseeding created the least amountof cover crop biomass, with no differences found among the other establishment methods that included drilling and sowing broadcast. At soybean planting timing, treatments with tillage had greater control of tall waterhemp than those without tillage. Wheat was shown to have the greatest weed suppressive capabilities, largely due to its ability to create high levels of residual biomass. Daikon radish produced the least biomass residue and had the poorest tall waterhemp control. The termination experiment of Elbon rye determined that treatments with rolling could impact soybean emergence and plant height largely due to dense biomass that lay flat onto the soil surface

Download or read book Cover Crops for Horseweed Conyza Canadensis L Control Before and During a Soybean Crop written by Andi Marie Christenson and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Increasing numbers of herbicide-resistant weed species require alternative methods of weed suppression to be examined. This study quantified the interaction between various cover crop or herbicide systems and horseweed [Conyza canadensis (L.)] growth. Fall cover crops of winter wheat [Triticum aestivum (L.)], winter rye [Secale cereal (L.)], barley [Hordeum vulgare (L.)] and annual ryegrass [Lolium multiflorum (L.)] were seeded in November 2012 and 2013. Spring cover crop of oat [Avena sativa (L.)] was seeded in April 2013 or rye was seeded in March 2014. All cover crops were no-till seeded into grain sorghum stubble [Sorghum bicolor (L.) Moench]. Four herbicide treatments were fall or spring applied, with and without residual. The spring non-residual treatment was also applied to plots of winter rye. Cover crop plots were split and terminated with a roller crimper or glyphosate application prior to soybean [Glycine max (L.) Merr.] planting to determine the effect of termination method on treatment performance. Soybean was planted in June 2013 and May 2014 and mechanically harvested in October of both years. Horseweed density, biomass accumulation, and soybean yield data were quantified. Horseweed height, whole plant seed production, and seed subsamples were recorded in the untreated fallow control, winter wheat, and winter rye plots in 2014. Horseweed suppression by winter rye approached 90%, levels similar to suppression by herbicide systems. In both years, herbicide plots had less than half the horseweed biomass than any of the cover crop systems. In 2013, soybean yields in herbicide plots were at least 1,500 kg ha−1, nearly more than double yields in cover crop plots. Soybean yields in 2014 were more consistent across treatments; barley and spring rye plots achieved yields equal to or greater than 2,000 kg ha−1. Winter rye and winter wheat reduced horseweed seed production by 60% compared to the untreated fallow control, with no effect on individual seed weight. Seed production varied across plants, with the untreated control producing the greatest number of seeds. Cover crops were successful at reducing horseweed biomass, suppressing horseweed pressure, preserving soybean biomass, and protecting soybean yields when compared to a fallow untreated control.

Download or read book Integrating Cover Crops in No till Corn and Soybean to Diversify Herbicide Resistant Weed Management in the Mid Atlantic written by Jess Marie Bunchek and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Widespread adoption of genetically-engineered, herbicide-resistant (HR) crops have simplified crop rotation diversity and the use of single-tactic, herbicide-based weed management programs. These practices have resulted in an HR weed epidemic, where glyphosate-resistant weeds are especially problematic. Glyphosate-resistant weeds like horseweed [Conyza canadensis (L.)] and pigweeds (Amaranthus spp.) threaten grower productivity and long-term efficacy of common agronomic herbicides. Thus, integrated weed management (IWM) programs that implement both ecological- and herbicide-based tactics are needed in no-till annual grain systems to (1) manage current HR weeds, (2) reduce HR selection pressure for evolution of resistance to other herbicides, (3) preserve effective herbicide technology, (4) enhance environmental stewardship, (5) safeguard soil conservation gains, and (6) maintain farm profits and productivity. To address these goals, we established three field studies at two sites in the Mid-Atlantic and identified combinations of cover crop and herbicide tactics that achieve effective season-long annual weed management, minimize HR selection pressure, and increase sustainability by reducing herbicide inputs. The first two studies assessed the complementarity of cover crops treatments and herbicide programs in corn and soybean, where integrating a cover crop treatment combined with applying a spring, pre-plant burndown herbicide application as well as a POST-emergent application provided the most effective season-long annual weed control. The third study assessed cover crop treatments and varied management practices, such as planting and termination dates, on HR selection pressure reduction at the time of herbicide applications. While cover crops intercepted a portion of the burndown herbicide application from reaching the soil surface, weeds were effectively controlled by the cover crops before the application, thus reducing the HR selection pressure.

Download or read book Cover Crop and Herbicide Combinations for Session long Weed Control in Dry Beans written by Ryan T. Johnson and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Herbicides remain an important weed management tool in dry edible beans but reducing reliance on herbicides through integrated weed management practices is important. The objective of this study was to evaluate the effect of cover crops in combination with herbicides for weed suppression in dry bean (Phaseolus vulgaris). Field studies were conducted in 2021 and 2022 near Lingle and Powell, WY. Three small grain cover crop (winter wheat) treatments were planted in March (early), or in April (late), with a control treatment of no cover crop. Pinto beans were planted in early June and the cover crop was terminated with glyphosate on the day of bean planting. Each cover crop whole-plot was divided into four split-plots consisting of the following herbicide treatments: no herbicide, preemergence (PRE) herbicide application only (pendimethalin + dimethenamid-P), postemergence (POST) herbicide application only (bentazon + imazamox), and sequential PRE and POST herbicide application. Spring-planted winter wheat cover crop combined with herbicides had a beneficial effect on dry bean yield in 3 out of the 4 studies. Weed control failure in all treatments occurred at Lingle, 2022 due to presence of herbicide-resistant kochia. For the other three sites, POST herbicide had a greater impact on protecting dry bean yield than PRE herbicides or cover crops. Cover crop helped to reduce kochia and lambsquarters density but was even more consistent at reducing the aboveground biomass of these two weed species. The wheat cover crop failed to reduce hairy nightshade density, but this weed species was controlled by either PRE or POST herbicide application. POST herbicide application contributed the most to protecting dry bean grain yield, followed closely by PRE herbicide, and lastly by the cover crop.