CONTROL OF QUACKGRASS IN FALLOW FROM SEVERAL GLYPHOSATE PLUS TILLAGE TREATMENTS AND ITS EFFECT ON THE SUBSEQUENT YIELD OF BARLEY

1989 ◽  
Vol 69 (4) ◽  
pp. 1207-1215 ◽  
Author(s):  
A. L. DARWENT ◽  
M. N. BAIG ◽  
A. W. GALLAGHER ◽  
L. P. LEFKOVITCH
Keyword(s):  
Ammonium Sulfate ◽  
Herbicide Application ◽  
Spray Volume ◽  
Culm Density ◽  
Tillage Operations ◽  
Agropyron Repens

The control of quackgrass (Agropyron repens (L.) Beauv.) using glyphosate applied with either a conventional sprayer or a rope wick applicator, each followed by several levels of tillage, was studied in 1983, 1984 and 1985. With the conventional sprayer, glyphosate was either applied alone or with ammonium sulfate (3.4 kg ha−1) and the surfactant, nonylphenoxy polyethoxy ethanol (0.5% vol/vol of spray volume). Applications made with the sprayer were more effective in reducing quackgrass culm density than those made with the rope wick applicator. The density of quackgrass culms declined as the number of tillage operations increased from one, performed at 115 or more days after herbicide application (DAT), to three performed at 5–8, 39–60 and 115 or more DAT. Doubling the rate of sprayer-applied glyphosate, from 0.8 to 1.7 kg acid equivalent ha−1, did not result in a reduction in the density of quackgrass culms. However, in 1 of the 2 years in which comparisons were made, both of these treatments reduced the density of quackgrass culms more than a similar application of glyphosate alone at 0.5 kg ha−1. The addition of ammonium sulfate and surfactant to glyphosate enhanced quackgrass control only at the 0.5 kg ha−1 rate and only in 1 of 2 yr at that rate. Glyphosate, applied at 0.5 kg ha−1 with the sprayer, and followed by three tillage operations consistently reduced the density of quackgrass culms by 95% or more. Both the herbicide and the tillage treatments resulted in increases in the yield of barley seeded the following year. In 2 of the 3 years, barley yields, averaged across tillage treatments, were greater in the plots where the sprayer had been used to apply the glyphosate treatments than in the plots where the rope wick applicator had been used. Barley yields decreased as the quackgrass culm density increased, although other factors seemed to have influenced the yields in one of the years.Key words: Glyphosate, tillage, barley, quackgrass, fallow

CONTROL OF QUACKGRASS WITH GLYPHOSATE AND ADDITIVES

1988 ◽  
Vol 68 (4) ◽  
pp. 1095-1101 ◽  
Author(s):  
J. A. IVANY
Keyword(s):  
Ammonium Sulphate ◽  
Nonionic Surfactants ◽  
Acceptable Level ◽  
Spray Volume ◽  
Agropyron Repens

Addition of nonionic surfactants nonylphenoxyl polyethoxy ethanol at 0.1% of total spray volume (vol/vol), tallow amine ethoxylate at 0.5% (vol/vol), or oil concentrate at 1% (vol/vol) to commercially formulated glyphosate applied at 0.25 and 0.5 kg a.i. ha−1 improved control of quackgrass [(Agropyron repens (L.) Beauv.)]. However, the improvement was not sufficient to provide an acceptable level of control of quackgrass. Addition of ammonium sulphate to glyphosate gave significantly greater control of quackgrass at all three rates of glyphosate. In one of the two experiments, control with 0.5 kg a.i. ha−1 of glyphosate was comparable to that of 1.0 kg a.i. ha−1. Addition of either of the three surfactants to the ammonium sulphate and glyphosate combinations did not further enhance control.Key words: Ammonium sulphate, nonylphenoxy polyethoxy ethanol, tallow amine ethoxylate, oil concentrate, Agropyron repens (L.) Beauv.

Great Plains Yucca (Yucca glauca) Control on Shortgrass Rangelands

2018 ◽  
Vol 33 (1) ◽  
pp. 192-195
Author(s):  
Walter H. Fick ◽  
Keith Harmoney
Keyword(s):  
Great Plains ◽  
Native Species ◽  
Individual Plant ◽  
Optimum Control ◽  
Single Application ◽  
Herbicide Application ◽  
Forage Plants ◽  
Percent Mortality ◽  
Spray Volume

AbstractGreat Plains yucca is a native species that competes with forage plants for space and water and at high densities may warrant control. The objective of this study was to determine the efficacy of seven herbicides applied in the spring or fall for Great Plains yucca control. Six foliar herbicides applied by ground application at 187 L ha−1 spray volume, one herbicide applied to individual plant whorls, and a nontreated check were established in June and September of 2009 and 2011. Percent mortality was determined 12 to 16 mo after herbicide application. Most herbicides gave similar control between the 2 yr, with triclopyr in diesel applied to individual plant whorls at 10 g L−1 providing the greatest control at 83%. Most herbicides applied in June near the blooming stage of Great Plains yucca were more effective than September treatments. June treatments providing the greatest reduction in yucca densities were metsulfuron + dicamba + 2,4-D amine + 2,4-D low volatile ester (LVE) at 21 + 113 + 325 + 431 g ae ha−1, metsulfuron + aminopyralid + triclopyr at 49 + 9 + 227 g ha−1, metsulfuron + chlorsulfuron + 2,4-D LVE at 34 + 11 + 431 g ha−1, and metsulfuron + aminopyralid + 2,4-D LVE at 49 + 9 + 431 g ha−1. A single application of a foliar herbicide provided a maximum of 72% mortality of Great Plains yucca, suggesting that repeat application may be necessary to achieve optimum control.

Spray Volume, Formulation, Ammonium Sulfate, and Nozzle Effects on Glyphosate Efficacy1

2003 ◽  
Vol 17 (3) ◽  
pp. 589-598 ◽  
Author(s):  
BRADFORD K. RAMSDALE ◽  
CALVIN G. MESSERSMITH ◽  
JOHN D. NALEWAJA
Keyword(s):  
Ammonium Sulfate ◽  
Spray Volume

Characterization of the Spray Droplet Spectra and Patterns of Four Venturi-Type Drift Reduction Nozzles

1999 ◽  
Vol 13 (4) ◽  
pp. 765-770 ◽  
Author(s):  
Robert E. Etheridge ◽  
Alvin R. Womac ◽  
Thomas C. Mueller
Keyword(s):  
Particle Size ◽  
Volume Distribution ◽  
Laboratory Studies ◽  
Herbicide Application ◽  
Spray Droplet ◽  
Particle Size Analyzer ◽  
Drift Potential ◽  
Median Diameter ◽  
Spray Volume

Laboratory studies were conducted using a Malvern laser droplet/particle size analyzer to determine the droplet spectra of several venturi-type drift reduction nozzles compared to a standard single, elliptical-orifice flat fan nozzle. Spray solutions of glufosinate, glyphosate, and paraquat were applied through all combinations of five nozzle types (four drift reduction), three tip sizes, and four application pressures. Nozzles were also evaluated for pattern uniformity using water plus surfactant at one pressure. When averaged over herbicide, tip size, and pressure the venturi nozzles collectively produced larger volume median diameter (VMD) droplets than the standard nozzle. The percentage of spray volume in droplets < 205 μm was less for the venturi nozzles (17%) than for the standard nozzle (65%) when averaged across all factors. The order of herbicides producing the largest droplets was paraquat (470 μm) > glyphosate (460 μm) > glufosinate (400 μm), as measured by VMD. The venturi nozzles were more variable in their spray volume distribution than the standard nozzle. Utilization of venturi-type nozzles may minimize the drift potential of the herbicides evaluated but could also lead to uneven herbicide application and subsequent erratic weed control.

Effect of Adjuvant and Spray Volume on Quackgrass (Agropyron repens) Control with Selective Postemergence Herbicides

1987 ◽  
Vol 1 (2) ◽  
pp. 129-132 ◽  
Author(s):  
James J. Kells ◽  
Gunawan Wanamarta
Keyword(s):  
Glycine Max ◽  
Butyl Ester ◽  
Propanoic Acid ◽  
Affect Control ◽  
Spray Volume ◽  
Growing Conditions ◽  
Postemergence Herbicides ◽  
Agropyron Repens ◽  
Spray Adjuvants

Soybean-based [Glycine max(L.) Merr.] and petroleum-based crop oil concentrates were equally effective as spray adjuvants for control of quackgrass [Agropyron repens(L.) Beauv. #3AGRRE] with the butyl ester of fluazifop {[±)-2-[4-[[5-(trifluoromethyl)-2-pyridinyl] oxy] phenoxy] propanoic acid} and sethoxydim {2-[1-(ethoxyimino)butyl]-5-[2-(ethylthio)propyl]-3-hydroxy-2-cyclohexen-1-one}. With favorable growing conditions at application in 1983 and 1985, an adjuvant concentration of 1% (v/v) with these herbicides was adequate for quackgrass control. Unfavorable growing conditions at application in 1984 resulted in unacceptable quackgrass control, and spray volume did not affect control. However, increasing the adjuvant concentration to 4% (v/v) with either herbicide applied in a spray volume of 70 L/ha nearly doubled quackgrass control. In 1983 and 1985, equal or greater quackgrass control with each herbicide was achieved with spray volumes as low as 35 L/ha compared to 280 L/ha.

scholarly journals Factors influencing broadcast-herbicide control of huisache (Vachellia farnesiana)

2019 ◽  
Vol 33 (6) ◽  
pp. 773-777
Author(s):  
Megan K. Clayton ◽  
Robert K. Lyons
Keyword(s):  
Soil Moisture ◽  
Droplet Size ◽  
Treatment Plant ◽  
South Texas ◽  
Plant Mortality ◽  
Herbicide Application ◽  
Spray Droplet ◽  
Cumulative Rainfall ◽  
Spray Volume ◽  
Average Plant

AbstractHuisache is a major brush problem on native rangelands and pastures in South Texas. Although herbicide applications to foliage provide very high plant-kill levels, the same herbicides have not proven reliable when applied as broadcast ground or aerial foliar treatments. Aerial and ground broadcast herbicide foliar treatments were applied to 31 huisache sites. Soil temperature and soil moisture were measured at a depth of 30 cm at the time of herbicide application. Cumulative rainfall before herbicide application was recorded. Across all aerial treatments, plant mortality was 69% for plants shorter than 2 m versus 40% for plants taller than 2 m. Across all aerial- and ground-treated sites, plants shorter than 2 m had an average 89% mortality when cumulative 2-wk rainfall was at least 50 mm, versus 72% mortality with cumulative rainfall less than 50 mm. Average plant mortality was 84% when 4-wk cumulative rainfall was at least 76 mm, versus 71% with rainfall less than 76 mm; and 85% when, on a dry-to-wet scale of 0 to 10, soil moisture measured at least 8, versus 71% when soil moisture measured less than 8. In a separate aerial trial, plant-mortality effects of spray droplet size (417, 630, and 800 µm) and spray volume (37.4 L ha−1 and 93.5 L ha−1) were replicated and tested at a single study site in 2014. Plant mortality was lowest for the 93.5 L ha−1 and 800 µm treatment. Plant mortality rates for other treatments were similar, demonstrating a greater importance of droplet size than spray volume. Targeting huisache trees shorter than 2 m, when cumulative rainfall has reached at least 50 mm or at least 76 mm 2 or 4 wk before application, respectively, as well as maintaining spray droplet sizes no larger than 630 µm can increase herbicide efficacy with foliar broadcast applications.

Control of Quackgrass (Elytrigia repens) and Field Mint (Mentha arvensis) with Glyphosate Applied Preharvest

1997 ◽  
Vol 11 (4) ◽  
pp. 744-747 ◽  
Author(s):  
Jerry A. Ivany ◽  
Douglas J. Doohan
Keyword(s):  
Moisture Content ◽  
Grain Yield ◽  
Ammonium Sulfate ◽  
Field Experiments ◽  
Mentha Arvensis ◽  
Elytrigia Repens ◽  
Grain Moisture ◽  
Spray Volume ◽  
One Year

Field experiments showed that quackgrass could be controlled by glyphosate applied preharvest to barley. In separate experiments, field mint was controlled by glyphosate applied pre- and postharvest to barley and wheat. Suppression of quackgrass regrowth one year following treatment was 90% or greater when glyphosate was applied at 0.9 kg ai/ha alone or at 0.45 kg ai/ha in combination with both tallow amine ethoxylate at 0.5% of total spray volume and ammonium sulfate at 3 kg/ha. Field mint shoot counts were reduced 84% the year following treatment when glyphosate was applied at 0.25 kg ai/ha and 95% when applied at 1.0 kg ai/ha. Suppression of field mint shoot regrowth the following year was 84% when glyphosate was applied postharvest and 93% when applied preharvest. Addition of tallow amine ethoxylate did not improve field mint control. Glyphosate applied preharvest to barley and wheat at less than 30% grain moisture content had no effect on grain yield.

Control of Quackgrass (Agropyron repens) in Soybeans (Glycine max) with HOE 29152

Weed Science ◽  
1980 ◽  
Vol 28 (5) ◽  
pp. 493-498 ◽  
Author(s):  
F. L. Young ◽  
D. L. Wyse
Keyword(s):  
Glycine Max ◽  
Field Studies ◽  
Herbicide Application ◽  
Short Term ◽  
Chamber Studies ◽  
The One ◽  
Growth Chamber Studies ◽  
Soybean Leaves ◽  
Rhizome Buds ◽  
Agropyron Repens

In field studies, postemergence applications of HOE 29152 {2-[4-(trifluoromethyl phenoxy)phenoxy] propanoate} at rates of 1.68 to 3.36 kg/ha effectively controlled quackgrass [Agropyron repens(L.) Beauv.] when applied to plants in the one- to three-leaf stage. Control was still effective the following year. The addition of a surfactant to HOE 29152 did not increase quackgrass control, but it did increase soybean [Glycine max(L.) Merr.] injury. Cultivation 1 or 7 days after herbicide application increased the efficacy of HOE 29152 on quackgrass. Due to abundant moisture in 1977, untreated quackgrass-infested plots yielded as much as the weed-free plots. However, in 1976, a very dry year, the control of quackgrass with HOE 29152 resulted in greatly increased soybean yields. In greenhouse studies, postemergence applications of HOE 29152 at rates of 0.56 to 3.36 kg/ha effectively killed rhizome buds and reduced shoot dry weights of quackgrass. The phytotoxicity of HOE 29152 at 0.56 kg/ha was less at a postspray temperature of 36 C than at 17 or 27 C; however, the phytotoxicity of HOE 29152 at rates of 1.68 and 3.36 kg/ha was similar at all three temperatures. HOE 29152 can volatilize from soybean leaves, with volatility greater at 38 C than at 21 C. Postemergence applications injured soybeans similarly in field and growth chamber studies. Injury was observed only on leaves that were expanded at time of treatment, was short-term, and was most prevalent at 3.36 kg/ha.

Meadow Knapweed (Centaurea debeauxii) Response to Herbicides and Mechanical Control

2014 ◽  
Vol 7 (3) ◽  
pp. 503-510 ◽  
Author(s):  
Timothy W. Miller ◽  
Cathy Lucero
Keyword(s):  
United States ◽  
Ammonium Sulfate ◽  
The United States ◽  
Early Flowering ◽  
Herbicide Application ◽  
Slight Effect ◽  
Mechanical Control ◽  
Application Timing ◽  
Stages Of Growth ◽  
Grass Biomass

AbstractMeadow knapweed is a fertile European hybrid between black and brown knapweed that has expanded its North American distribution to 27 of the United States and four provinces in Canada. Two experiments were conducted on meadow knapweed in northwestern Washington to determine (1) whether meadow knapweed is similarly sensitive to several herbicides commonly used to control related knapweeds, (2) if herbicide application timing plays a role in control of meadow knapweed, and (3) whether mowing before, after, or instead of herbicide treatment can aid in meadow knapweed control. In the first experiment, herbicides were applied to meadow knapweed at rosette or bolting stages of growth, and again with the same herbicides in the autumn. In the summer following treatment, clopyralid alone or with 2,4-D, dicamba + 2,4-D, and triclopyr ester + 2,4-D ester provided 81 to 100% meadow knapweed control; the only other treatment providing similar control was glyphosate + ammonium sulfate applied at bolting and in autumn in the 2004 to 2005 trial. In the second experiment, combinations of mowing and dicamba + 2,4-D were applied at rosette or early flowering stages of growth. In the 2002 to 2003 trial, control when dicamba + 2,4-D was used exceeded 90%, except when meadow knapweed was mowed at rosette and sprayed at early flowering (78% control). Mowing twice the previous year had only a slight effect on meadow knapweed (10% control). Grass biomass exceeded meadow knapweed biomass in all herbicide-treated plots. In the 2004 to 2005 trial, meadow knapweed control and grass biomass was maximized when plots were mowed at rosette and treated with dicamba + 2,4-D at early flowering or when treated twice with these herbicides; these were the only treatments where grass biomass exceeded meadow knapweed biomass.

Sign in / Sign up

Export Citation Format

Share Document