Johnsongrass (Sorghum halepense) Control with Imazethapyr and Haloxyfop in Conventional and Vertical-tilled Soybean (Glycine max)

Field studies in conventional and vertical-tilled soybeans were conducted in 1992/93 and 1993/94 at four locations in Argentina to compare the efficacy of imazethapyr and haloxyfop for johnsongrass control. Control was evaluated by measuring frequency of johnsongrass-infested areas at the beginning of the 1992/93 and 1993/94 growing seasons. Relative johnsongrass leaf area and number of rhizome phytomers within infested areas also was evaluated. Herbicide application reduced frequency of infested areas in the 1992/93 growing season. Frequency of infested areas increased in check plots. No differences were found among herbicide treatments, suggesting that the effect of imazethapyr was as high as that observed for specific graminicides. Reduction in frequency of infested areas caused by herbicide treatments was accompanied to some extent by a decrease in intensity of infestation within infested patches assessed by measuring johnsongrass relative leaf area. Phytomer population levels, on the other hand, were reduced only after two consecutive years of herbicide application. No differences were found among herbicide treatments in terms of impact on both measures of weed abundance. Johnsongrass responded similarly to all treatments regardless of tillage system.

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Impact of postemergence herbicides on soybean injury and canopy formation

Weed Technology ◽

10.1017/wet.2020.55 ◽

2020 ◽

Vol 34 (5) ◽

pp. 727-734

Author(s):

Grant L. Priess ◽

Jason K. Norsworthy ◽

Trenton L. Roberts ◽

Edward E. Gbur

Keyword(s):

Growth Stage ◽

Yield Loss ◽

Soil Surface ◽

Growing Season ◽

Field Studies ◽

Herbicide Application ◽

Canopy Volume ◽

Herbicide Treatments ◽

Soybean Canopy ◽

Postemergence Herbicides

AbstractField studies were conducted in 2017 and 2018 in Arkansas to evaluate the injury caused by herbicides on soybean canopy formation and yield. Fomesafen, acifluorfen, S-metolachlor + fomesafen, and S-metolachlor + fomesafen + chlorimuron alone and in combination with glufosinate were applied to glufosinate-resistant soybean at the V2 growth stage. Soybean injury resulting from these labeled herbicide treatments ranged from 9% to 25% at 2 wk after application. This level of injury resulted in a 4-, 5-, 6-, and 6-d delay in soybean reaching 80% groundcover following fomesafen, acifluorfen, S-metolachlor + fomesafen, and S-metolachlor + fomesafen + chlorimuron, respectively. There was a 2-d delay in soybean reaching a canopy volume of 15,000 cm3 following each of the four herbicide treatments. The addition of glufosinate to the herbicide applications resulted in longer delays in canopy formation with every herbicide treatment except glufosinate + fomesafen. Fomesafen, acifluorfen, S-metolachlor + fomesafen, and S-metolachlor + fomesafen + chlorimuron, each applied with glufosinate, delayed soybean from reaching 80% groundcover by 2, 7, 8, and 9 d, respectively, and delayed the number of days for soybean to reach a canopy volume of 15,000 cm3 by 2, 3, 2, and 2 d, respectively. No yield loss occurred with any herbicide application. A delay in percent groundcover in soybean allows sunlight to reach the soil surface for longer periods throughout the growing season, possibly promoting late-season weed germination and the need for an additional POST herbicide application.

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A Weed Compaction Roller System for Use with Mechanical Herbicide Application

Northern Journal of Applied Forestry ◽

10.1093/njaf/23.1.66 ◽

2006 ◽

Vol 23 (1) ◽

pp. 66-69 ◽

Cited By ~ 1

Author(s):

Adam H. Wiese ◽

Daniel A. Netzer ◽

Don E. Riemenschneider ◽

Ronald S. Zalesny

Keyword(s):

Tree Plantations ◽

Diameter Growth ◽

Herbicide Application ◽

Treatment Combination ◽

Invasive Weed ◽

Vegetation Control ◽

Growing Seasons ◽

Herbicide Treatments ◽

Roller System ◽

The Cost

Abstract We designed, constructed, and field-tested a versatile and unique weed compaction roller system that can be used with mechanical herbicide application for invasive weed control in tree plantations, agronomic settings, and areas where localized flora and fauna are in danger of elimination from the landscape. The weed compaction roller system combined with herbicide application generally had greater vegetation control compared with using only herbicide treatments or the unsprayed control. The roller system-herbicide treatment combination showed substantial total vegetation control two growing seasons after application without impacting diameter growth of the crop trees, which supports the need for less frequent entries into the field. The cost of the roller system was approximately $300.00.

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Response of wildlife to forest herbicide applications in northern coniferous ecosystems

Canadian Journal of Forest Research ◽

10.1139/x93-283 ◽

1993 ◽

Vol 23 (10) ◽

pp. 2286-2299 ◽

Cited By ~ 43

Author(s):

R.A. Lautenschlager

Keyword(s):

Small Mammal ◽

Growing Season ◽

Sampling Techniques ◽

Mammal Species ◽

Growing Seasons ◽

Disturbed Areas ◽

Herbicide Treatments ◽

Species Specific ◽

Small Mammal Species ◽

Coniferous Ecosystems

Reviewed studies of the effects of forest herbicide applications on wildlife often lacked replication, pretreatment information, and (or) were conducted for only one or two growing seasons after treatment. Because of these problems, as well as the use of dissimilar sampling techniques, study conclusions have sometimes been contradictory. A review of eight studies of the effects of herbicide treatments on northern songbird populations in regenerating clearcuts indicates that total songbird populations are seldom reduced during the growing season after treatment. Densities of species that use early successional brushy, deciduous cover are sometimes reduced, while densities of species which commonly use more open areas, sometimes increase. A review of 14 studies of the effects of herbicide treatments on small mammals indicates that like songbirds, small mammal responses are species specific. Some species are unaffected, while some select and others avoid herbicide-treated areas. Only studies that use kill or removal trapping to study small mammal responses show density reductions associated with herbicide treatment. It seems that some small mammal species may be reluctant to venture into disturbed areas, although residents in those areas are apparently not affected by the disturbance. Fourteen relevant studies examined the effects of conifer release treatments on moose and deer foods and habitat use. Conifer release treatments reduce the availability of moose browse for as long as four growing seasons after treatment. The degree of reduction during the growing season after treatment varies with the herbicide and rate used. Deer use of treated areas remains unchanged or increases during the first growing season after treatment. Eight years after treating a naturally regenerated spruce–fir stand browse was three to seven times more abundant on treated than on control plots (depending on the chemical and rate used). Forage quality (nitrogen, ash, and moisture) of crop trees increased one growing season after the soil-active herbicide simazine was applied to control competition around outplanted 3-year-old balsam fir seedlings.

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Response of Johnsongrass (Sorghum halepense) and Imidazolinone-Resistant Corn (Zea mays) to AC 263,222

Weed Technology ◽

10.1017/s0890037x00046078 ◽

1999 ◽

Vol 13 (3) ◽

pp. 484-488 ◽

Cited By ~ 11

Author(s):

John W. Wilcut ◽

John S. Richburg ◽

F. Robert Walls

Keyword(s):

Zea Mays ◽

Weed Control ◽

Untreated Control ◽

Field Studies ◽

Sorghum Halepense ◽

Corn Yield ◽

Redroot Pigweed ◽

Herbicide Treatments ◽

Ac 263,222 ◽

Large Crabgrass

Field studies were conducted in 1992 and 1993 to evaluate AC 263,222 applied postemergence (POST) alone and as a mixture with atrazine or bentazon for weed control in imidazolinone-resistant corn. Nicosulfuron alone and nicosulfuron plus atrazine were also evaluated. Herbicide treatments were applied following surface-banded applications of two insecticides, carbofuran or terbufos at planting. Crop sensitivity to POST herbicides, corn yield, and weed control was not affected by insecticide treatments. AC 263,222 at 36 and 72 g ai/ha controlled rhizomatous johnsongrass 88 and 99%, respectively, which was equivalent to nicosulfuron applied alone or with atrazine. AC 263,222 at 72 g/ha controlled large crabgrass 99% and redroot pigweed 100%, and this level of control exceeded that obtained with nicosulfuron alone. AC 263,222 at 72 g/ha controlled sicklepod and morningglory species 99 and 98%, respectively. Nicosulfuron alone or with atrazine controlled these two species less than AC 263,222 at 72 g/ha. Addition of bentazon or atrazine to AC 263,222 did not improve control of any species compared with the higher rate of AC 263,222 at 72 g/ha applied alone. Corn yield increased over the untreated control when POST herbicide(s) were applied, but there were no differences in yield among herbicide treatments.

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Mechanism for the enhanced effect of mowing followed by glyphosate application to resprouts of perennial pepperweed (Lepidium latifolium)

Weed Science ◽

10.1614/ws-03-024r ◽

2004 ◽

Vol 52 (1) ◽

pp. 14-23 ◽

Cited By ~ 16

Author(s):

Mark J. Renz ◽

Joseph M. DiTomaso

Keyword(s):

Leaf Area ◽

Plant Architecture ◽

Canopy Structure ◽

Field Studies ◽

Herbicide Application ◽

Deposition Pattern ◽

Application Timing ◽

Spray Solution ◽

Area Distribution ◽

Leaf Area Distribution

Herbicides currently registered for use near water have been ineffective for control of perennial pepperweed. Previous research has demonstrated that mowing followed by an application of glyphosate at 3.33 kg ae ha−1to resprouting tissue can enhance the control of perennial pepperweed. The objectives of this study were to determine the mechanism(s) responsible for the enhanced effectiveness of glyphosate in combination with mowing. Mowing plants altered the leaf area distribution within the canopy. In mowed areas, the majority of leaf area was in the basal third of the canopy, whereas the bulk of the leaf area was in the top third of the canopy in unmowed plots. This change in plant architecture affected the deposition pattern of the spray solution. Unmowed plants retained 49 to 98% and 42 to 83% of a dye solution within the middle and top thirds of the canopy at the Colusa and Woodland sites, respectively, with only 1.9 to 6.0% dye deposited on the basal third of the canopy at both sites. In contrast, mowed plants had 18 to 34% and 26 to 70% of the dye retained in the basal third of the canopy at the Colusa and Woodland sites, respectively. Greenhouse studies showed that14C-glyphosate applied to basal leaves of mowed plants translocated significantly more to belowground tissue. Unmowed plants accumulated 0.37% of the applied14C-glyphosate in belowground tissue 48 h after labeling. In contrast, mowed plants accumulated 6.7%14C-glyphosate in the belowground tissue. In field studies, estimates of basipetal seasonal translocation rates using total nonstructural carbohydrate pools of roots indicate that mowing did not change the translocation rate. However, the delay in application timing to allow plants to resprout appeared to synchronize applications with maximal translocation of carbohydrates to belowground structures. We hypothesize that the change in the canopy structure of perennial pepperweed after mowing results in fewer aboveground sinks and greater deposition of herbicide to basal leaves where it can preferentially be translocated to the root system. Furthermore, the delay between mowing and resprouting synchronized maximal belowground translocation rates with herbicide application timing. These factors all appear to be involved in the observed enhanced control of perennial pepperweed when combining mowing and glyphosate.

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Cotton tolerance to halauxifen-methyl applied preplant

Weed Technology ◽

10.1017/wet.2019.41 ◽

2019 ◽

Vol 33 (04) ◽

pp. 620-626

Author(s):

M. Carter Askew ◽

Charles W. Cahoon ◽

Alan C. York ◽

Michael L. Flessner ◽

David B. Langston ◽

...

Keyword(s):

Cotton Plant ◽

Cotton Yield ◽

Seed Cotton ◽

Growth Reduction ◽

Herbicide Application ◽

Rotation Interval ◽

Growing Seasons ◽

Group 4 ◽

Herbicide Treatments ◽

Auxin Herbicides

AbstractAuxin herbicides are used in combinations to control glyphosate-resistant horseweed preplant burndown. Herbicide labels for 2,4-D–containing products require a 30-d rotation interval for planting cotton cultivars not resistant to 2,4-D. Dicamba labels require an accumulation of 2.5 cm of rain plus 21 d per 280 g ae ha–1 rotation interval for planting cotton cultivars not resistant to dicamba. Previous research has shown that cotton injury caused by dicamba applied 14 d before planting was transient with little effect on cotton yield, whereas 2,4-D has little effect on cotton when applied 7 d prior to planting. Injury caused by dicamba and 2,4-D is inversely related to rainfall received between herbicide application and cotton planting. Experiments were conducted to evaluate cotton tolerance to halauxifen-methyl, a new Group 4 herbicide, applied at intervals shorter than labeled requirements. Experiments were established near Painter and Suffolk, VA, and Belvidere, Clayton, Eure, Lewiston, and Rocky Mount, NC, during the 2017 and 2018 growing seasons. Herbicide treatments included halauxifen, dicamba, and 2,4-D applied 4, 3, 2, 1, and 0 wk before planting (WBP). Visible estimates of cotton growth reduction and total injury were collected 1, 2, and 4 wk after cotton emergence (WAE). Cotton stand and percentage of plants with distorted leaves were recorded 2 and 4 WAE. Cotton plant heights were recorded 4 and 8 WAE. Halauxifen was less injurious (9%) than dicamba (26%) or 2,4-D (21%) 2 WAE when herbicides were applied 0 WBP. Cotton stand reduction 2 WAE by halauxifen was less than 2,4-D and dicamba when applied 0 WBP. Injury observed from herbicides applied 1, 2, 3, and 4 WBP was minor, and no significant differences in cotton stand were observed. Early-season cotton injury was transient, and seed cotton yield was unaffected by any treatment.

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Influence of Herbicides on the Development of Internal Necrosis of Sweetpotato

Weed Technology ◽

10.1017/wet.2017.60 ◽

2017 ◽

Vol 31 (6) ◽

pp. 863-869 ◽

Cited By ~ 2

Author(s):

Shawn C. Beam ◽

Katherine M. Jennings ◽

David W. Monks ◽

Jonathan R. Schultheis ◽

Sushila Chaudhari

Keyword(s):

Field Studies ◽

Herbicide Application ◽

Storage Roots ◽

Herbicide Treatment ◽

Production Study ◽

Herbicide Treatments ◽

Internal Necrosis ◽

Field Production

Field studies were conducted to determine the influence of herbicides on the development of internal necrosis (IN) in sweetpotato storage roots. In a slip propagation study, herbicide treatments included PRE application (immediately after covering seed roots with soil) of clomazone (0.42, 0.84 kg ai ha-1), flumioxazin (0.11, 0.21 kg ai ha-1), fomesafen (0.28, 0.56 kg ai ha-1), linuron (0.56, 1.12 kg ai ha-1),S-metolachlor (0.8, 1.6 kg ai ha-1), flumioxazin plusS-metolachlor (0.11 + 0.8 or 1.6 kg ha-1), and napropamide (1.12, 2.24 kg ai ha-1), and POST application (2 to 4 wk prior to cutting slips) of ethephon (0.84, 1.26 kg ai ha-1) and paraquat (0.14, 0.28 kg ai ha-1). In a field production study, flumioxazin, fomesafen, linuron, and paraquat were applied PREPLANT (one d prior to sweetpotato transplanting), clomazone,S-metolachlor, and napropamide were applied PRE [4 d after transplanting (DAP)], flumioxazin PREPLANT followed by (fb) S-metolachlor PRE, and ethephon applied POST (2 wk prior to harvest). Herbicide rates were similar to those used in the slip propagation study. Yield of sweetpotato in both studies was not affected by herbicide treatment. In both studies, IN incidence and severity increased with time and was greatest at 60 d after curing. No difference was observed between herbicide treatments for IN incidence and severity in the slip production study which indicates herbicide application at time of slip propagation does not impact the development of IN. In the field production study, the only treatment that increased IN incidence compared to the nontreated was ethephon with 53% and 2.3 incidence and severity, respectively. The presence of IN affected roots in nontreated plots indicates that some other pre- or post-curing factors other than herbicides are responsible for the development of IN. However, the ethephon application prior to sweetpotato root harvest escalates the development of IN.

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Evaluating Soil Solarization for Weed Control and Strawberry (Fragariaxananassa) Yield in Annual Plasticulture Production

Weed Technology ◽

10.1017/wet.2017.4 ◽

2017 ◽

Vol 31 (3) ◽

pp. 455-463 ◽

Cited By ~ 4

Author(s):

Jayesh B. Samtani ◽

Jeffrey Derr ◽

Mikel A. Conway ◽

Roy D. Flanagan

Keyword(s):

Data Collection ◽

Weed Control ◽

Crop Yield ◽

Crop Yields ◽

Growing Season ◽

Field Studies ◽

Soil Solarization ◽

Row Spacing ◽

Weed Density ◽

Growing Seasons

Field studies were initiated in the 2013-14 and 2014-15 growing seasons to evaluate the potential of soil solarization (SS) treatments for their efficacy on weed control and crop yields and to compare SS to 1,3-dichloropropene (1,3-D)+chloropicrin (Pic) fumigation. Each replicate was a bed with dimension 10.6 m long by 0.8 m wide on top. The center 4.6 m length of each bed, referred to as plots, was used for strawberry plug transplanting and data collection. Treatments included: i) 1,3-D+Pic (39% 1,3-dichloropropene+59.6% chloropicrin) that was shank-fumigated in beds at 157 kg ha−1and covered with VIF on August 30 in both seasons; ii) SS for a 6 wk duration initiated on August 15, 2013 and August 21, 2014 by covering the bed with 1 mil clear polyethylene tarp; iii) SS for a 4wk duration initiated on September 6, 2013 and September 3, 2014; iv) SS 4 wk treatment initiated September 6, 2013 and September 3, 2014 and replaced with black VIF on October 4, 2013 and October 1, 2014 and v) a nontreated control covered with black VIF on October 4, 2013 and October 1, 2014. In both seasons, following completion of the preplant treatments, ‘Chandler’ strawberry was planted in two rows at a 36 cm in-row spacing in plots during the first wk of October. Over both seasons, the 6 wk SS treatment consistently lowered the weed density compared to the nontreated control. Weed density in the 6wk SS treatment was not statistically different from the 4wk SS treatments in the 2013-14 growing season. In both seasons, crop yield in the 4 wk SS was significantly lower than other treatments.

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Weed Control in Glyphosate-Resistant Corn as Affected by Preemergence Herbicide and Timing of Postemergence Herbicide Application

Weed Technology ◽

10.1614/wt-04-288r.1 ◽

2006 ◽

Vol 20 (3) ◽

pp. 564-570 ◽

Cited By ~ 23

Author(s):

Robert G. Parker ◽

Alan C. York ◽

David L. Jordan

Keyword(s):

Grain Yield ◽

Weed Control ◽

Field Studies ◽

Herbicide Application ◽

Application Timing ◽

Common Lambsquarters ◽

Herbicide Treatments ◽

Prickly Sida ◽

Smooth Pigweed ◽

Or Applications

Field studies were conducted at three locations during both 2002 and 2003 to evaluate weed control and response of glyphosate-resistant (GR) corn to glyphosate or nicosulfuron plus atrazine applied POST at three application timings with and without alachlor plus atrazine applied PRE. The POST herbicides were applied timely (5- to 9-cm weeds) or applications were delayed 1 or 2 wk. All treatments, except the weedy check, were followed by glyphosate postemergence-directed (PDIR) 4 wk after the timely POST application. Common lambsquarters, common ragweed, Palmer amaranth, prickly sida, and smooth pigweed were controlled at least 94% regardless of PRE or POST treatments. Large crabgrass and fall panicum were controlled at least 96% by glyphosate regardless of PRE herbicide or POST application timing. In contrast, control by nicosulfuron plus atrazine POST in the absence of PRE herbicide decreased as application was delayed. Sicklepod was controlled at least 94% when POST herbicides were applied timely, but control by both POST herbicide treatments decreased with delayed application regardless of PRE herbicide. Tall morningglory was controlled 93% or greater by POST herbicides applied timely. Control by both POST herbicide treatments decreased as application was delayed, with glyphosate being affected more by timing than nicosulfuron plus atrazine. Corn grain yield was similar with glyphosate and nicosulfuron plus atrazine. Yield was unaffected by POST application timing when PRE herbicides were included. Without PRE herbicide, grain yield decreased as POST herbicide application was delayed.

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White spruce establishment in two boreal Ontario mixedwoods: 13-year results

The Forestry Chronicle ◽

10.5558/tfc79127-1 ◽

2003 ◽

Vol 79 (1) ◽

pp. 127-131

Author(s):

R F Sutton ◽

T P Weldon

Keyword(s):

Picea Glauca ◽

Untreated Control ◽

Growing Season ◽

White Spruce ◽

Site Preparation ◽

Mechanical Site Preparation ◽

Treatment Performance ◽

Growing Seasons ◽

Control Growth ◽

Herbicide Treatments

An experiment to investigate techniques for establishing white spruce (Picea glauca [Moench] Voss) in boreal Ontario mixedwood was begun in 1985 in Oates Twp. Eight 25-tree plots were established in each of nine treatments: three mechanical site preparation treatments (none, disk- trenching, and toothed-blading) in combination with three kinds of chemical weed control (none, Velpar L® at the time of planting, and Vision® during the second growing season). The experiment was repeated the following year in the adjacent township of Oswald. The mechanical treatments were applied as planned, but the herbicide treatments deviated somewhat from the plan. Fifth-year results were reported in this journal in 1995. In the eighth growing season, a ground-spray release treatment with Vision® was applied to four randomly selected 25-tree plots in each original treatment. Performance of white spruce after 13 growing seasons was significantly influenced by site preparation: survival averaged 65 and 79% without release in the blading and trenching treatments, respectively, and 22% in the untreated control; with release, survival averaged 74 and 80% in the blading and trenching treatments, respectively, and 24% in the untreated control. Growth was greatest in the bladed treatment, poorest by far in the untreated control. The ineffectiveness of herbicides in these experiments is surprising in view of successes elsewhere. The modest response to release was significant for 13th -year increment. Key words: site preparation, toothed blading, trenching, release

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