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Coyote brush is a native shrub common on California coastal prairies. It is largely unpalatable to cattle and is an aggressive encroacher on open prairies; as such, it is a threat to livestock production on some of California’s most productive rangelands. This experiment assessed the effectiveness of four common herbicides and three application methods to control coyote brush. Glyphosate, imazapyr, triclopyr, and 2,4-deoxynivalenol (2,4-D) were analyzed using foliar spray and drizzle applications. Only glyphosate and imazapyr were analyzed using basal bark injection. All applications resulted in a short-term decrease in coyote brush cover, but plants that were treated with the selective herbicides triclopyr or 2,4-D appeared to recover after a year. The nonselective herbicides glyphosate and imazapyr performed well 12 months after application. Glyphosate and imazapyr performed similarly in controlling both large and small plants. No difference existed when comparing foliar spray and drizzle application methods, but both outperformed basal bark injection. As in previous studies, the drizzle method proved the most effective, requiring less labor and chemical than foliar application, and less threat of drift to non-target species. These results suggest that coyote brush can be controlled through both foliar spray and drizzle applications of glyphosate or imazapyr.

We examined the 14-year effects of experimentally varied chemical site preparation and release treatments in a Pinus taeda L. plantation in Dillwyn, Virginia, US. The study examined the effects of timing (July, September, or October) for imazapyr site preparation, with or without the addition of sulfometuron methyl (SFM), year-one release from herbaceous weeds using SFM plus imazapyr, and year-two release treatment using imazapyr at a rate to control hardwoods. Chemical site preparation treatment applications exhibited a reduction in competition basal area ha-1 and an increase in pine volume compared to the check, however, application timing was the most influential factor in determining the effectiveness of the treatments. September 3rd and October 1st applications averaged less competing vegetation basal area than the year-two release and the check plots. At age 14-years, competing vegetation reduced individual pine tree volumes by 5.6% for every one m2 of competing vegetation basal area. [ABSTRACT FROM AUTHOR]

Abstract Despite the widespread use of titanium dioxide (TiO2) in photocatalytic applications, its inherent limitations, such as low efficiency under visible light and rapid recombination of electron-hole pairs, hinder its effectiveness in environmental remediation. This study presents a comparative investigation of TiO2-based composites, including TiO2/ZrO2, ZnO, Ta2O3, SnO, Fe2O3, and CuO, aiming to assess their potential for enhancing photocatalytic applications. Photocatalysis holds promise in environmental remediation, water purification, and energy conversion, with TiO2 being a prominent photocatalyst. To improve efficiency and broaden applicability, various metal oxide composites have been explored. Composites were synthesized and characterized using techniques such as XRD, SEM, TEM, and zeta potential analysis to evaluate their structural and morphological properties. Photocatalytic performance was assessed by degrading herbicide Imazapyr under UV illumination. Results revealed that, the photo-activity of all prepared composites were more effective than the photo-activity of commercial hombikat UV-100. The photonic-efficiency is arranged according to the order TiO2/CuO > TiO2/SnO > TiO2/ZnO > TiO2/Ta2O3 > TiO2/ZrO2 > TiO2/Fe2O3 > Hombikat TiO2-UV100. All composites exhibited superior performance, attributed to enhanced light absorption and charge separation. The study underscores the potential of these composites for environmental remediation and energy conservation, offering valuable insights for the development of advanced photocatalysts.

【Objective】This study aimed to assess the effectiveness of imazapyr in controlling Spartina alterniflora and to analyze its impact on soil ecosystem, so as to provide theoretical basis for scientific control of S. alterniflora.【Method】In the typical S. alterniflora invasion area in coastal Guangxi, a control sample plot L0 and three experimental sample plots (L1-L3) treated with different concentrations of imazapyr(3000, 3750, 4500 g/hm²)were established. Soil samples at depths of 0-20 cm were collected at 1, 30, 60 and 120 d of the experiment. The contents of total organic carbon (TOC), nitrogen (N), phosphorus (P), potassium (K) were analyzed. Meanwhile, the growth status and control rate of S. alterniflora were recorded.【Result】The growth of S. alterniflora was greatly inhibited by spraying with imazapyr, and the elimination efficiency were 54.35%, 92.99% and 100.00% after 30, 60 and 120 d, respectively. However, secondary invasion occurred in the experimental area. The application of imazapyr caused the death of S. alterniflora, significantly reduced the TOC content of soil in the experimental plots (P＜0.05), with surface soil showing a clear trend of carbon loss. The application of imazapyr had no significant effect on soil TN content (P＞0.05), but significantly increased the contents of ammoniacal nitrogen (NH4+-N), total phosphorus (TP), available phosphorus (AP), total potassium (TK) and available potassium (AK), and significantly decreased nitrate nitrogen(NO3--N) content. There was no significant difference in nutrient content among the experimental plots.【Conclusion】Imazapyr shows a high control rate of S. alterniflora, however, while effectively controlling S. alterniflora, the application of imazapyr resulted in soil carbon loss indirectly, but promoted the accumulation of soil nutrients. Therefore, the global control model should be adopted in the control project to avoid the secondary invasion of S. alterniflora, and it is recommended to plant native vegetation to occupy the ecological niche of the original S. alterniflora, so as to improve the soil carbon sequestering capacity and the stability of the soil ecosystem. [ABSTRACT FROM AUTHOR]

Swamp titi (Cyrilla racemiflora L.) is a vigorous native shrub or small tree found in poorly drained areas of the southeastern U.S. Coastal Plain. In the absence of fire, it creates dense thickets that prevent herbaceous groundcover in ephemeral wetlands, degrading habitat for uncommon and endangered amphibians and other genera. In our study, aquatic herbicides and methods of application were examined at two forests in north Florida for restoration of ephemeral wetland habitat to benefit wetland‐breeding amphibians. Glyphosate, imazapyr, and combinations of glyphosate and imazapyr were tested in four study protocols that included an operational standard (triclopyr), treatment method control, and untreated control where appropriate. Results of foliar protocols (targeting rootstocks less than 1.5 m tall) demonstrated that glyphosate provided better titi control than imazapyr (average of 79% vs. 12% mortality), there was no strong improvement with the addition of imazapyr to glyphosate (84% mortality), glyphosate treatments had titi mortality as high or higher than the triclopyr operational treatment (57% mortality), and that methylated seed oil surfactant improved glyphosate efficacy but might have been antagonistic for combination treatments. Glyphosate and imazapyr cut stump treatments did not provide higher efficacy than the triclopyr standard treatment (60% mortality). Cut stem treatments (targeting rootstocks greater than 1.5 m tall) provided the highest level of control averaging 97, 90, 97, and 80% mortality for glyphosate, imazapyr, combination treatments, and triclopyr standard, respectively. Only directed foliar sprays reduced total groundcover and graminoid cover, with triclopyr treatment giving the least reduction of desired herbaceous groundcover. [ABSTRACT FROM AUTHOR]

Herbicides are used in agriculture to control harmful crop weeds, prevent algae proliferation, and enhance macrophyte growth. Herbicide contamination of water bodies might exert toxic effects on fish in different development stages. Sperm, embryos, and adults of Astyanax altiparanae were used as a model to examine the detrimental effects of the following herbicide formulations: Roundup Transorb® (glyphosate), Arsenal® NA (imazapyr), and Reglone® (diquat). The lethal concentration 50 (LC50) values for adults using glyphosate and imazapyr were 3.14 mg/L and 4.59 mg/L, respectively, while the LC50 was higher than 28 mg/L for diquat. For the initial stages of embryo development, LC50 values were 16.52 mg/L glyphosate, 9.33 mg/L imazapyr, and 1084 mg/L diquat. Inhibition of sperm motility was noted at 252 mg/L glyphosate, 137 mg/L imazapyr, and 11,300 mg/L diquat, with an average sperm viability of 12.5%, 73.2%, and 89.3%, respectively, compared to 87.5% detected to control. A.altiparanae exhibited different sensitivities to the herbicide formulations investigated in the developmental stages evaluated. Roundup Transorb® exposure was more toxic for adults, while Arsenal® NA was most harmful for early embryonic development and inhibited sperm motility. Reglone® demonstrated low toxicity for A.altiparanae compared to Roundup Transorb® and Arsenal® NA. A.altiparanae may be considered an emerging fish model for toxicological studies for the neotropical region due to its wide distribution and biological characteristics. [ABSTRACT FROM AUTHOR]

Invasive knotweeds (Reynoutria spp.) pose an ongoing challenge for weed management programs worldwide, requiring years of persistent treatment. In this study, we tested efficacy of diquat applied as foliar spray early in the growing season for short‐term suppression, and for potential to boost long‐term control when applied sequentially with a mid‐season treatment of imazapyr. We evaluated responses of knotweeds (R. japonica, R. × bohemica, and R. sachelinensis) treated with one of three diquat concentrations (0.25%, 0.50%, or 1.0%, v/v), using multiple metrics to capture changes in aboveground plant density and abundance. Canopy cover and biomass were significantly reduced by all diquat concentrations and resembled pre‐treatment conditions at 8WAT, reflecting the shift toward reduced stem heights in treated compared with untreated plots. Stem counts at 8WAT, however, did not differ in response to diquat treatments. Sequentially applied early‐season diquat and mid‐season imazapyr treatments reduced canopy cover (66%–82%), biomass (65%–91%), and stem density (57%–79%) when evaluated 1 year after treatment; reductions were greatest in plots treated with medium and high diquat concentrations, suggesting that diquat treatments may have an additive effect. Overall, our study establishes rates of diquat to reduce biomass of invasive knotweed, and supports additional testing to assess improvement in long‐term control when used sequentially with a systemic herbicide. [ABSTRACT FROM AUTHOR]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract Castor bean (Ricinus communis L.) is an important cultivated oilseed. Seeds contain ricinoleic acid, a valuable product for a variety of industries. Castor cake is a residue of ricinoleic manufacture and could be used as animal feed due to its high amount of protein. However, castor cake contains ricin and RCA120, both highly toxic and allergenic proteins. In 2017, we reported the development of a transgenic event (named TB14S-5D) with an undetectable amount of ricin/RCA120. In the present work, we evaluate TB14S-5D for tolerance to the herbicide imazapyr, as it contains the selectable marker gene, ahas, which was previously isolated from Arabidopsis thaliana and contains a mutation at position 653 bp. In addition, we demonstrated that the ricin coding genes are stably silenced over three generations.

Invasion by smooth cordgrass (Spartina alterniflora Loisel) has greatly impacted the intertidal ecosystems of China. Worldwide, chemical control is the most widely used method to control Spartina species, but it has not been widely implemented along the Chinese coast due to concerns about the potential impacts of herbicide residues on the environment and organisms. Macrobenthos, both natural and cultured on intertidal mudflats, is an important seafood resource, so human food safety is a particular concern. Here we tested the effectiveness of imazapyr (an imidazolinone herbicide inhibiting the synthesis of branched-chain amino acids) in controlling S. alterniflora from August 2020 to June 2021 on the Jiangsu Coast, an area severely impacted by S. alterniflora. We used two different concentrations of the herbicide and monitored the density of S. alterniflora seedlings and flower spikelets, the effects of herbicide use on macrobenthos, and residues in organisms and the environment at different times post-application. Ten months after application, imazapyr had killed all plants and within 30 days it inhibited the two reproductive processes of germination and flowering; there were no significant differences between the two concentrations used. Imazapyr residues were detected in the environment for up to 14 days post-application, but at very low concentrations and exponentially decreased with time. No residues were found in any macrobenthos. Imazapyr use did not result in a reduction of macrobenthos density. We conclude that the herbicide imazapyr effectively removes S. alterniflora with little collateral damage to other organisms and the environment. However, in view of the relatively small scale of our trials and the great extent of S. alterniflora in many sites in China, we recommend that larger scale field trails be conducted to assess any potential adverse effects when imazapyr is used at a landscape level.

Castor bean (Ricinus communis L.) is an important cultivated oilseed. Seeds contain ricinoleic acid, a valuable product for a variety of industries. Castor cake is a residue of ricinoleic manufacture and could be used as animal feed due to its high amount of protein. However, castor cake contains ricin and RCA120, both highly toxic and allergenic proteins. In 2017, we reported the development of a transgenic event (named TB14S-5D) with an undetectable amount of ricin/RCA120. In the present work, we evaluate TB14S-5D for tolerance to the herbicide imazapyr, as it contains the selectable marker gene, ahas, which was previously isolated from Arabidopsis thaliana and contains a mutation at position 653 bp. In addition, we demonstrated that the ricin coding genes are stably silenced over three generations. [ABSTRACT FROM AUTHOR]

Imidazolinones are a group of herbicides with high potential of leaching and long half-lives that are posing a threat to water resources' quality especially in tropical areas. Biochar, a carbon-rich bio-sorbent, has shown its ability to stabilise organic substances in soils and therefore, potentially is able to reduce their leaching. Biochar is a sustainable and cost-effective material which can be produced from locally available wastes. This work, for the first time, evaluated the biochar's effects on leaching of two polar members of imidazolinones family namely imazapic and imazapyr, and also Onduty® which is a mixture of these two herbicides, in heavy soil of tropical paddy fields. Leaching columns accompanied with artificial irrigation were used during the laboratory experiment. The herbicides were extracted from both collected leachates and soil columns. Soil amendment with designed biochars significantly reduced the herbicides' leaching percentages. Oil palm empty fruit bunch (OPEFB) and rice husk (RH) were used as pyrolysis feedstock. About 16% of the applied imazapic was leached out from biochar-free soil. For RH and OPEFB biochar-amended soils, the amounts were 4.3% and 3.6%, respectively. The highest percentage of imazapyr leached out from non-amended soil was (14.2%) followed by RH (4.0%) and OPEFB (2.8%) in biochar-amended soils. Also, 15.2% of the applied Onduty® was leached from non-amended soil. Adding RH and OPEFB biochars could reduce the herbicide leaching to 4.2% and 3.0%, respectively. Soil amended with biochars retained the higher percentages of the herbicides in top 7.5 cm depths. The media sorption capacities were negatively correlated to the amounts of herbicides leached out from soils but positively to the amounts of the herbicides remaining in the soil. Total amount of herbicides adsorbed by biochars-amended soils was more than 95%. Cation/water bridging ion exchange, ligand exchange, electrostatic attraction, and hydrophobic partitioning are the main ways imidazolinones can be adsorbed to soil. It was concluded that biochar application has the potential to reduce polar imidazolinones' leaching and their environmental pollution. The custom-engineered biochars can specifically control the pesticides transfer and then can certainly enhance the biochars' commercial values for their applications in the environment. [ABSTRACT FROM AUTHOR]

There are increased concerns about the thyroidal effects of many anthropogenic substances in the environment. These substances include agricultural pesticides and industrial and pharmaceutical chemicals among others. Their potential thyroidal effects are of serious health and ecological concerns, as thyroid hormones mediate numerous physiological processes, including growth regulation, general metabolism and metamorphosis in metamorphic animals. This study assessed thyroidal activities of Arsenal formulation (Imazapyr) at environmentally relevant concentrations of 0.5, 2.0 and 3.5 mg/L following a Xenopus metamorphosis assay (XEMA). The result shows that the Arsenal formulation significantly delayed the tadpole development, reduced the hind-limb length (HLL) and increased the whole-body mass (WBM) at a concentration of 3.5 mg/L relative to the control exposure. In histopathology, the formulation increased the epithelium height, at all exposure concentrations, but reduced the colloidal area at 0.5 and 2 mg/L, respectively, and the gland area at 2 mg/L relative to the control. Consequently, the Arsenal formulation is thyroid-active at environmentally relevant concentrations and poses a threat to both human and wildlife, especially metamorphic organisms. With this exposure impact, more studies are imperative to further characterise other endocrine-disrupting potential of this formulation, while future applications should be reduced or restricted to less risk environment, if it cannot be stopped from sensitive aquatic systems [ABSTRACT FROM AUTHOR]

In this probe, a convenient template was practiced to fabricate mesoporous PdO–TiO2 nanocomposites using a sol–gel routine. Photo-destruction of the herbicide imazapyr was adapted to figure out the photonic efficacies of the formulated nanocomposites. Furthermore, the appraised photonic efficacies were correlated with the photonic efficacies retained by commercial P25 Degussa as well as mesoporous titania. Progression of the tetragonal anatase phase of titania was entrenched via X-ray diffraction inquire. PdO–TiO2 nanocomposite accommodating 0.9% PdO possessed superlative photonic efficacy of 34.8% whereas, commercial P25 Degussa and mesoporous titania possessed photonic efficacies of 1.0 and 2.0% respectively revealing the superior photonic efficacy of the fabricated nanocomposites in comparison to other relevant photo-catalysts. In conclusion, PdO–titania nanocomposites acquiring enhanced charge carriers' separation could be fabricated along with the collaborating action of both titania and PdO nanoparticles. Furthermore, the tremendous stability of the fabricated nanocomposites was ascertained via its implementation up to five cycles keeping its photo-catalytic performance without alteration. Hence, PdO nanoparticles could be formulated as fruitful promoters for the photo-catalytic aspects possessed by mesoporous titania. [ABSTRACT FROM AUTHOR]

The removal of the commonly used herbicides is essential for environmental remediation. In this study, mesoporous TiO2 photocatalysts modified with PtO were synthetized by the template-assisted scheme to develop highly effective materials for the elimination of Imazapyr herbicide under visible-light preservation. The effect of the PtO loading was investigated, and the xPtO-TiO2 materials were deeply considered by N2 physisorption, XRD, HRTEM, FTIR, DRS UV-Vis, Raman, XPS, PL and photocurrent measurements. Total Imazapyr photodegradation was archived on mesoporous TiO2 photocatalysts loaded with 0.6 and 0.8 wt% of PtO. The optimized xPtO-TiO2 photocatalyst degrades the Imazapyr under solar light more efficiently than the pure TiO2 and the commercial Degussa P25 (photoefficiency of 35%, 1%, and 0.5%, respectively). The improvement in the photoefficiency of the xPtO-TiO2 photocatalysts respect to the pure TiO2 was associated to the cooperative effect between PtO and TiO2 nanoparticles leading to a lessening in the energy gap and lower recombination of excited electron-hole pairs. The optimized 0.6PtO-TiO2 photocatalyst demonstrated to be stable and recyclable after up to five consecutive photocatalytic runs. Therefore, it can be a potential candidate for the significant mineralization of Imazapyr herbicide under solar light irradiation. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Plant Science is the property of Canadian Science Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The phytostimulation is a phytoremediation technique that can be used to remediate area contaminated with herbicides. It is necessary to select plants with high capacity to stimulate soil microbial activity. The present work aimed at evaluating seven plant species regarding their ability to phytostimulate soil and enhance the degradation of the herbicides imazethapyr, imazapic and imazapyr in a lowland soil. An Alfisol Albaqualf was cultivated with the following species, Canavalia ensiformis, Glycine max, Oryza sativa cultivar PUITÁ INTA CL, Lolium multiflorum, Vicia sativa and consortium Lotus corniculatus + Trifolium repens. The rhizosphere of these plants and non-rhizospheric (uncultivated soil) as a control were contaminated in laboratory with analytical standart of the three herbicides, at rates of 0, 150, 300 and 750 g a.i. ha−1, in separate assays. Biodegradation was estimated by quantifying C–CO2 production and through analysis of herbicides residues in soil using liquid chromatography. Results show that biodegradation of herbicides imazethapyr, imazapic and imazapyr was higher in vegetated soil than in unvegetated soil. The leguminous species Canavalia ensiformis, Glycine max, Vicia sativa and consortium of Lotus corniculatus + Trifolium repens showed a great capacity to promote soil microbial, resulting in average biodegradation rates of 91, 92 and 93% for herbicides imazethapyr, imazapic and imazapyr in soil, respectively. [ABSTRACT FROM AUTHOR]

Analysis of herbicides sorption behavior in soil is critical in predicting their fate and possible harmful side effects in the environment. Application of polar imidazolinone herbicides is growing in tropical agricultural fields. Imidazolinones have high leaching potential and are persistent. In this study, adsorption–desorption of imazapic and imazapyr herbicides were evaluated in different types of Malaysian agricultural soils. Effects of soil parameters were also investigated on the soils' sorption capacities. The adsorption data fitted best to Freundlich isotherm (R2 > 0.991). The herbicides adsorptions were physical and spontaneous processes as ΔG values were negative and below 40 kJ/mol. The adsorption correlated positively with clay content, total organic carbon (TOC) content, and cation exchange capacity (CEC). There were strong negative correlations between hysteresis index and these factors indicating their importance in imidazolinones immobilization and, thus, their pollution reduction in the environment. [ABSTRACT FROM AUTHOR]

• The optical absorbance is enhanced by the in situ electro-reduction of herbicide. • A tubular lead electrode was made by a flowing-bath electrodeposition procedure. • The levels of detection reached meets the legal tolerances of imazapyr. • It's the first non-chromatographic method developed for imazapyr determination. • The only pretreatment required is set a 0.6 M ionic strength and pH equal to 0.5. A new flow injection analysis method with spectro-electrochemical detection (FIA/SEC) to determine trace levels of imazapyr on water samples is presented. The non-chromatographic method involves the use of a bench photometer, a single-potential potentiostat, a low pressure pumping system and a home-made spectro-electrochemical flow detector (SEC-FD), specifically adapted for the described method and using a stainless steel/electrolytic lead/lead chloride (SS/ e -Pb/PbCl 2) working electrode. The limit of quantification (LOQ) reached for the optimized work parameters was 0.02 µg/mL, the relative standard deviation (RSD) in the whole range of linear response was less than 2% and a wide linear response range from 0.005 to 6.0 µg/mL was obtained. A standard addition method was used to determine the imazapyr amount in natural waters containing commercial formulation of such herbicide, the Recovery % has values close to 105%. The method performance makes it suitable to analyze the legal imazapyr tolerances established by the U.S. EPA avoiding the use of expensive chromatographic equipments and/or complicated sample preparations. [ABSTRACT FROM AUTHOR]

The residual activity of herbicides may be detrimental to the environment, requiring analysis of the persistent residues in the soil and water. A field study was conducted to measure the residues of Imidazolinone (IMI) in three Clearfield® rice field soils at three different locations in Malaysia. The analyses of IMI in the soil samples were carried out using a high-performance liquid chromatography (HPLC). These herbicides are widely used; however, few studies have been conducted on both residues, especially in the context of Malaysian soil. Residues of imazapic and imazapyr were found to fall within 0.03–0.58 µg/mL and 0.03–1.96 µg/mL, respectively, in three locations. IMI herbicides are persistent in the soil, and their residues remain for up to 85 days after application. A pre-harvest study was suggested for these herbicides on water, which will provide a clearer indicator on the use of IMI in Clearfield® rice fields. [ABSTRACT FROM AUTHOR]

Schematic preparation process of the molecular imprinted probe with hybrid ratio fluorescent and visual detection of IMA. [Display omitted] • A hybrid molecularly imprinted ratio fluorescent probe was constructed for the detection of imazapyr (IMA). • The proposed method has the potential for on-site visual detection of IMA. • Under UV irradiation, the fluorescence color changes from red to blue. • A new way is provided for the detection of IMA residues in food and drugs. Imazapyr (IMA) is a widely used herbicide, and the detection of its residue is of great significance for agricultural cultivation and preventing the potential risk to human health. In this work, a molecularly imprinted probe was prepared by sol–gel method with hybrid ratio fluorescent for specifically visual detection of IMA for the first time, embedding CdTe quantum dots (QDs) (λ em = 580 nm) in molecularly imprinted polymers as response signal and Si QDs (λ em = 445 nm) in silicon dioxide as internal signal. After binding with IMA, the fluorescence at 580 nm was quenched gradually while the fluorescence intensity at 445 nm remained constant. Under optimal conditions, the fluorescent intensity ratio (I 580 /I 445) shows a good linear relationship with IMA concentration in the range of 5.0–80.0 μM, with a detection limit of 1.4 μM. Additionally, the fluorescent color of the probe solution changes from red to blue under the ultraviolet irradiation of 365 nm, indicating it has the potential for on-site visual detection. And it had been successfully applied to the detection of IMA in Puerariae Lobatae Radix and soil. [ABSTRACT FROM AUTHOR]

Alopecurus myosuroides seeds were sampled from 32 winter wheat fields from 2010 to 2014. Resistance to herbicides was detected in 17 A. myosuroides populations. In addition to single resistance to herbicides, cross-resistance and multiple resistance to acetolactate synthase (ALS)- and acetyl-coenzyme A carboxylase (ACCase)-inhibiting herbicides were found. Application of sulfometuron and imazapyr was unable to control some of the resistant biotypes in this study. This result implies that resistance in these populations is due to a target site mechanism. The A. myosuroides biotypes resistant to ACCase-inhibiting herbicides varied in their responses to derivatives of aryloxy-phenoxy-propionic acid (FOPs), cyclohexanediones (DIMs) and phenylpyrazolines (DENs). Resistant biotypes of A. myosuroides that could not be controlled with fenoxaprop-P-ethyl (FOP) and pinoxaden (DEN) were controlled with clethodim (DIM).

Abstract Ease synthesis of mesoporous g-C 3 N 4 /TiO 2 nanocrystals at various C 3 N 4 contents (1–50 wt%) was performed by mixing tetrabutyl orthotitanate and g-C 3 N 4 throughout sol-gel avenue with existence template. The photooxidation of the herbicide imazapyr was chosen as a probe molecule to explore the photocatalytic performance of the prepared photocatalysts compared to that of the commercially P-25 along with g-C 3 N 4. TEM images exhibited that TiO 2 nanoparticles have very small particle size in the range of 5–10 nm and g-C 3 N 4 sheet-like nanoparticles possess characteristic for graphitic carbon nitride. The most efficient photocatalyst toward all the prepared samples was 10% g-C 3 N 4 /TiO 2 nanocrystals. The photonic efficiency of 10% g-C 3 N 4 /TiO 2 nanocrystals is 100 and 3 times greater than pure g-C 3 N 4 and P-25, respectively. The construction of mesoporous TiO 2 and g-C 3 N 4 with heterogeneity produces a synergistic effect that provides an efficient charge carriers transfer. The highest photocatalytic efficiency can be explained by large surface area, narrow band gap energy, small particles size, and efficient charge carriers' separation. [ABSTRACT FROM AUTHOR]

Cynodon dactylon (Bermudagrass) is an invasive grass found in some southwestern U.S. grasslands and is linked to decreased wildlife abundance. Cynodon dactylon removal is a necessary first step in many native grassland restoration projects. We evaluated seven C. dactylon removal methods in three Texas ecoregions, seeking to determine which most effectively suppressed C. dactylon growth in varying environmental conditions. We applied treatments to 355-m2 plots throughout summer 2015 and measured aboveground, living plant biomass, height, canopy cover, and species richness within plots in April–July 2016. Six treatments reduced (p ≤ 0.05) C. dactylon canopy cover compared to untreated controls at all study sites: single and repeated glyphosate herbicide applications—with or without shredding C. dactylon to 3-cm height two weeks prior, a single imazapyr herbicide application, and a glyphosate, imazapic, and imazapyr herbicide combination all resulted in ≥ 98.60% C. dactylon canopy cover and biomass reduction. A single glyphosate application reduced C. dactylon canopy cover 72.13 ± 27.74% compared to controls. Shredding grass and overseeding Vicia villosa (hairy vetch) reduced (p ≤ 0.05) C. dactylon biomass 49.45 ± 6.92% and height 13.58 ± 0.04% but did not decrease canopy cover relative to controls in any ecoregion. Overseeding V. villosa and shredding C. dactylon prior to herbicide application resulted in greater volunteer plant species richness and greater above-soil biomass. Treatment ability to suppress C. dactylon growth was similar across ecoregions. This implies land managers may use C. dactylon -suppression methodologies standardized for the entire state of Texas and likely beyond. By utilizing our results to effectively suppress C. dactylon, pastures can be prepared for conversion to native rangeland and prairie ecosystems. [ABSTRACT FROM AUTHOR]

Mesoporous In 2 O 3 -TiO 2 nanocomposites were successfully synthesized through sol gel approach in the presence of a suitable template. Their photonic efficiencies have been determined by measuring photooxidation of the herbicide imazapyr and compared with those of porous TiO 2 and of the commercial photocatalyst Hombikat UV-100. The X-ray diffraction patterns indicated the formation of tetragonal anatase and rutile phases of TiO 2 . The highest photonic efficiency values of 13.5% were obtained for the 0.1% In 2 O 3 -TiO 2 nanocomposite in comparison with a value of 12% for mesoporous TiO 2 and of 10.8% for commercial UV-100. As a result of the synergetic effect of TiO 2 (anatase & rutile) and In 2 O 3 nanoparticles, it is suggested that heterostructured In 2 O 3 -TiO 2 nanocomposites are formed and are promoting the separation of photogenerated charge carriers. Moreover, the In 2 O 3 -TiO 2 nanocomposites could be easily reused up to 5 times with only a slight decrease in their photocatalytic activity. The design for merging unique In 2 O 3 nanoparticles with a mesoporous TiO 2 network can be regarded as an innovation to further promote the photocatalytic properties of the latter. [ABSTRACT FROM AUTHOR]

The article reports that imazapyr herbicide induces male sterility in Imisun Sunflower during early stages of development and it also alters gene expression of acetohydroxyacid synthase and pollen yields.

The inclusion complexes of imazapyr (IMA) with 2-hydroxypropyl(β/γ) cyclodextrins (HP β/γ-CD), have been studied in aqueous media and in the solid state. In this work, fluorescence spectroscopy, electrospray-ionization mass spectrometry (ESI-MS), and 1 HNMR were used to investigate and characterize the inclusion complexes of IMA with the cyclodextrins in solutions. The solid state complexes were obtained by freeze drying and were characterized by Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (PXRD). The most predominant complexes of IMA with both hosts are the 1:1 guest: host complexes. The association constants of IMA-HP β-CD and IMA-HP γ-CD were 115 ± 23 and 215 ± 80 L mol −1 , respectively. Molecular dynamic (MD) simulations were used to monitor the mode of inclusion and also to investigate the stability of these complexes in aqueous media at atomistic levels. The results obtained have indicated that these inclusion complexes are highly stable in aqueous media, thereby corroborating the experimental results. Additionally, it has been demonstrated that in addition to hydrophobic effects and van der Waals interactions the presence of hydrogen bonding interactions of the type H O and CH O between the guest and the host have enhanced the stability of these complexes remarkably. [ABSTRACT FROM AUTHOR]

The rise in pesticides application has increased the need for better understanding of their ecological impacts. The global amphibian declines, for example, have been positively correlated with pesticides use. The differential susceptibility in the developmental stages of amphibians to chemical substances are still largely unknown. We examined the 96-h differential toxicity responses of embryos, premetamorphic and transitional larval stage of Xenopus laevis, to six formulated aquatic herbicide products containing the active ingredients of diquat dibromide (Midstream), glufosinate ammonium (Basta), imazapyr (Arsenal), and three glyphosate formulations (Roundup, Kilo Max, and Environ Glyphosate). The results showed the premetamorphic stage as the most sensitive to the herbicides toxicity. This study confirmed that the developmental stage at which amphibian are exposed to contaminants is critical to their survival and that the chemical contamination hypothesis of the global decline of amphibians should continue to be considered. This establishment of the premetamorphic larval as sensitive toxicity representative for all developmental stages of X. laevis means that this stage could be used more extensively in pesticides toxicity assessments. [ABSTRACT FROM AUTHOR]

This study investigates the degradation of imazapyr herbicide from wastewater by photocatalytic ozonation using TiO2 as a semiconductor. Effects of operational parameters on imazapyr removal efficiency including TiO2 dosing, initial herbicide concentration and pH were also studied. Obtained results showed that more than 90% of removal efficiency representing the disappearance of imazapyr was maintained until 7 μM in the presence of 200 mgL-1of UV100-TiO2. Otherwise, the degradation of imazapyr followed the first-order kinetics with a photocatalytic rate constant of 0.247 min-1, and complete degradation was achieved within 20 min using photocatalytic ozonation for 5 μM of Imazapyr at pH 7. [ABSTRACT FROM AUTHOR]

Cynodon dactylon (cynodon) is a weed that is particularly difficult to control due to its ability to reproduce readily using stolons and rhizomes. Although glyphosate is the most commonly used herbicide to control cynodon, current recommendations involve repetitive applications, which appear likely to select for resistance. Rotating glyphosate with herbicides that have different modes of action will be a more sustainable strategy for cynodon control. Earlier work suggested that the growth of cynodon is strongly inhibited by imazapyr, an herbicide that inhibits the acetohydroxy acid synthase (AHAS) enzyme. The optimum time for application of imazapyr on cynodon, and the subsequent inhibition of AHAS activity in cynodon are unknown. The aims of this study were firstly, to determine the effectiveness of inhibiting AHAS activity when applied at different times of the year, and secondly to compare the efficacy of foliar and root applications. Results showed that application time has a significant effect on the efficacy of imazapyr to inhibit enzyme activity, with mid–late summer being optimal, and furthermore that the herbicide can be absorbed by both the shoots and the roots. [ABSTRACT FROM AUTHOR]

The inclusion complexes of imazapyr (IMA) with cucurbit[ n ]uril, CB[ n ] (n = 6–8), have been investigated. Fluorescence spectroscopy, MALDI-TOF, and 1 HNMR were used to investigate and characterize the inclusion complexation of IMA and CB[ n ] in solutions. Whereas the solid state complexes have been characterized by Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (PXRD). IMA was found to form 1:1 complexes with CB[ n ] with association constants ranging from 5.80 × 10 2 –2.65 × 10 3 . The guest molecule IMA was found to encapsulate into the larger cavities of CB[7] and CB[8], whereas with CB[6] the molecule remains outside the cavity. Molecular dynamic (MD) simulations were used to follow the inclusion process at an atomistic level to study the mechanism and stability of inclusion. The results obtained showed that inclusion complexes of IMA with both CB[7] and CB[8] are highly stable in aqueous media, but the CB[6] smaller cavity size prohibited the formation of an inclusion complex with IMA. The results clearly show that in addition to hydrophobic effects the presence of hydrogen bonding has added greatly to the stability of these complexes. [ABSTRACT FROM AUTHOR]

Ca x MnO y -TiO 2 composites with different manganese oxide birnessite fractions (1–50 wt.%) have been synthesized based on the precipitation of birnessite and mixing with commercial titanium dioxide TiO 2 by mechanical grinding. The Ca x MnO y -TiO 2 composites exhibited high photoactivity for the decomposition of imazapyr herbicide and methylene blue under UV–vis illumination. The results suggested that a correlation exists between the calcium manganese oxide content, oxidation state and the changes in the UV–vis absorption properties. The composite with 5% Ca0.1MnOy/TiO 2 possessed the highest photocatalytic performance among all the as-obtained catalysts, the enhanced photocatalytic activity was attributed to the reduction of the band gap from 3.18 eV to 2.89 eV for pure TiO 2 and 5% Ca0.1MnOy/TiO 2 composite respectively. In addition, an efficient inhibition of electron-holes recombination rates due to the deposition of manganese oxide mainly on the surface of titanium dioxide producing an efficient charge separation, and transfer between the materials. Furthermore, the photocatalytic rate constant was found to increase from 0.124 min −1 to 0.542 min −1 and from 0.155 min −1 to 0.425 min −1 for methylene blue dye and imazapyr, in the presence of commercial titanium dioxide TiO 2 and 5% Ca 0.1 MnO y /TiO 2 composite, respectively. [ABSTRACT FROM AUTHOR]

A aggravating problems in forest management is weed interference, which is a factor that modifies adaptation and reduces plant growth. The use of herbicides is an indispensable practice to mitigate these effects in reforestation areas. This study aimed to evaluate the selectivity of glyphosate and imazapyr in native plants of the Brazilian Cerrado, such as: Schinus terebinthifolia (Anacardiaceae), Peltophorum dubium (Fabaceae) and Handroanthus albus (Bignoniaceae). The trial was carried out in a greenhouse at Unit of Aquidauana/UEMS. Experimental design was completely randomized, with seven treatments and five replications. Selectivity of the herbicides in the seedlings of these species was evaluated at 7, 14, 21, 28 and 60 days after application (DAA) of the herbicides, by means of a percentage scale of notes, where 0% corresponds to no injury and 100% corresponds to plant death. At the same time, for the weed control evaluation, visual analysis was also performed at 7, 14, 21, 28 and 60 DAA of the herbicides, where 100% was considered plant death and 0% no injury to weed. Imazapyr herbicide, when applied in the initial post-emergence in its lower level, it is selective to the tree species, but in the other concentrations it can affect differently the survival of them. Glyphosate herbicide was the least selective to the tree species in its different concentrations, causing phytotoxic effects with changes in the seedlings morphology. The results of this study could help in the integrated management of weeds and contribute to the efficient herbicide use in planting forest species in the Cerrado.

Fire-maintained pine ( Pinus spp.) forests, characterized by a diverse herbaceous layer, sparse midstory layer, and a dominant pine overstory, once covered approximately 30 million ha in the southeastern United States. Fire suppression, landscape changes, and land management changes have contributed to reduced suitability of many pine stands for fire-dependent species, including many avian species in regional decline. However, intensively managed loblolly pine ( P. taeda ) stands treated with prescribed fire and herbicide could help restore or maintain fire-dependent communities within working landscapes. Therefore, we investigated avian responses to combinations of prescribed fire and herbicide (imazapyr) treatments within a matrix of intensively managed pine stands in east-central Mississippi, USA. We used a randomized complete block design of 6 mid-rotation, thinned pine stands (blocks) each with 4 treatments (control, burn only, herbicide only, burn + herbicide) assigned to 10-ha experimental units. We applied imazapyr herbicide (Arsenal®) during fall 1999 and burned units during winter every 3 years, beginning in 2000. We conducted avian point counts from year pre-treatment (1999) through 9 years post-treatment (2000–2008) and summarized annual vegetation structure and composition. We used 34 of 64 observed avian species for analyses using mixed models, repeated measures ANCOVA. Across the 9-year post-treatment study period, fire and imazapyr differentially affected avian communities with our combination treatment (fire + imazapyr) favoring high-priority, open pine bird species most. However, remaining treatments (burn only, imazapyr only, controls) provided additional vegetation gradients for species preferring greater structure diversity or canopy coverage. Our results indicated that fire and herbicide treatments can maintain vegetation structure attractive to a bird community of high-conservation value, while concurrently meeting economic and sustainable forestry goals. Although primarily managed for economic gain, intensively managed forests can provide suitable habitat conditions for avian species of conservation concern helping land managers meet biodiversity objectives. [ABSTRACT FROM AUTHOR]

The unabated release of herbicide imazapyr into the soil and groundwater led to crop destruction and several pollution-related concerns. In this contribution, heterogeneous photocatalytic technique was employed utilizing mesoporous Ga 2 O 3 -TiO 2 nanocomposites for degrading imazapyr herbicide as a model pollutant molecule. Mesoporous Ga 2 O 3 -TiO 2 nanocomposites with varied Ga 2 O 3 contents (0–5 wt%) were synthesized through sol-gel process. XRD and Raman spectra exhibited extremely crystalline anatase TiO 2 phase at low Ga 2 O 3 content which gradually reduced with the increase of Ga 2 O 3 content. TEM images display uniform TiO 2 particles (10 ± 2 nm) with mesoporous structure. The mesoporous TiO 2 exhibits large surface areas of 167 m 2 g −1 , diminished to 108 m 2 g −1 upon 5% Ga 2 O 3 incorporation, with tunable mesopore diameter in the range of 3–9 nm. The photocatalytic efficiency of synthesized Ga 2 O 3 -TiO 2 nanocomposites was assessed by degrading imazapyr herbicide and comparing with commercial photocatalyst UV-100 and mesoporous Ga 2 O 3 under UV illumination. 0.1% Ga 2 O 3 -TiO 2 nanocomposite is considered the optimum photocatalyst, which degrades 98% of imazapyr herbicide within 180 min. Also, the photodegradation rate of imazapyr using 0.1% Ga 2 O 3 -TiO 2 nanocomposite is nearly 10 and 3-fold higher than that of mesoporous Ga 2 O 3 and UV-100, respectively. The high photonic efficiency and long-term stability of the mesoporous Ga 2 O 3 -TiO 2 nanocomposites are ascribed to its stronger oxidative capability in comparison with either mesoporous TiO 2 , Ga 2 O 3 or commercial UV-100. [ABSTRACT FROM AUTHOR]

Integrated vegetation management programs have successfully reduced the frequency and intensity of power line right-of-way management by promoting low-growing plant communities resistant to tree invasion. To examine whether these principles are transferable to northern ecosystems, researchers tested eight treatments at four sites in Yukon, Canada. Two herbicides, imazapyr and triclopyr, were applied by three methods, as well as a native grass seeding treatment and a mowing control. Vegetation cover was recorded prior to treatment and after one year along with herbicide damage assessments. Overall, treatments caused significant changes to vascular plant communities after one year. Short-term control of woody target species was greater in chemically- treated plots (66%-94%) than with mechanical methods (<55%). All treatments caused a minor reduction in non-target vegetation cover. In seeded plots, seedlings emerged but total non-target species cover was reduced by seedbed preparation. Triclopyr broadcast spray reduced non-target vegetation cover by <10%, but the common shrub, kinnickinnick (Arctostaphylos uva-ursi), was highly impacted. Selective application of triclopyr effectively controlled targets with minimal effects on non-target species. Imazapyr consistently caused more impacts to non-target plants than triclopyr. Both selective and non-selective imazapyr applications resulted in chlorosis, stunting, and deformity of shrubs and forbs one year after treatment. This suggests imazapyr can remain active in northern soils for at least 365 days as well as transfer to untreated plants. The range of sensitivities of boreal plant species to imazapyr and triclopyr and potential persistence in northern soils highlights the need for focused toxicity research in the North. [ABSTRACT FROM AUTHOR]

ABSTRACT Managers of commercial forests are increasingly expected to incorporate conservation of biodiversity in forest management plans, but a paucity of information exists regarding herpetofaunal responses to mid‐rotation release practices of dormant‐season prescribed fire and selective herbicide in intensively managed pine (Pinus spp.) stands. However, these management tools have demonstrated capabilities of improving conservation value in these forests in the southeastern United States. Therefore, we investigated summer herpetofaunal responses to factorial combinations of dormant‐season prescribed fire and a commonly used herbicide (imazapyr) with a randomized complete block design of 6 mid‐rotation pine stands with 4 experimental units in Mississippi, USA, to which we applied at random 1 of 4 treatments (i.e., burn only, herbicide only, burn + herbicide, control). We captured 814 reptiles and 3,699 amphibians of 17 and 16 species, respectively, using drift‐fence arrays during May and June, 1999–2007. Herpetofaunal assemblages only differed between burn + herbicide and control plots in 2002. Species‐specific responses were limited to differences across years within treatments and greater eastern fence lizard (Sceloporus undulatus) relative abundance in burned or herbicide‐treated sites soon after treatment. Furthermore, herpetofaunal associations with measured environmental variables (e.g., vegetation structure and biomass and trap‐site characteristics) did not indicate that treatment influenced fluctuations in species relative abundances. Consistent with past studies, forest managers of commercial pine forests using dormant‐season prescribed fire with or without imazapyr will most likely have minimal additional effects on herpetofaunal assemblages, but current knowledge gaps require additional research to better understand mechanisms of species abundance and persistence in these landscapes. © 2013 The Wildlife Society.

Alternanthera philoxeroides is a problematic invasive plant in many regions of the world that is difficult to control once naturalised. It poses a threat to agricultural productivity, biodiversity and social amenity values of aquatic environments. Significant research has been conducted internationally, regarding the efficacy of different herbicides for control of A. philoxeroides. However, no studies have looked at key aspects of control for effective management in an early stage of invasion of aquatic environments, hindering eradication and control programmes. This study evaluates the efficacy of herbicides and surfactants on key A. philoxeroides response metrics, including control of above-ground biomass, below-ground biomass and production of viable stem fragments. This study concluded that glyphosate (isopropylamine salt) minimises viable stem fragment production post-herbicide application, compared with imazapyr and metsulfuron, thus reducing the potential for dispersal throughout catchments and waterways. In contrast, imazapyr and metsulfuron provided more effective control than glyphosate for A. philoxeroides growing on exposed embankments. We propose that an effective management strategy for early invasion of aquatic A. philoxeroides, using herbicides, would be to conduct initial applications of glyphosate to control overwater biomass and limit dispersal of viable stem fragments. Once infestations have been forced back to the embankment, imazapyr or metsulfuron treatments will provide longer term control. [ABSTRACT FROM AUTHOR]

Terrestrial plant toxicity tests were conducted to determine the sensitivity of two boreal plants, yarrow ( Achillea millefolium L.) and fireweed ( Chamerion angustifolium L.), to the herbicides imazapyr and triclopyr. Both plants are common non-target species on northern powerline rights-of-way where the impacts of proposed herbicide applications are of concern. In the vegetative vigour test, triclopyr foliar spray caused extensive damage to A. millefolium at <50% of the maximum field application rate (inhibition concentration (IC) = 1443.8 g a.i. ha) and was lethal to C. angustifolium at the lowest dose tested (1210.9 g a.i. ha). Both species demonstrated extremely high sensitivity to imazapyr foliar spray: IC = 8.29 g a.i. ha and 4.82 g a.i. ha (<1.5% of the maximum field rate). The seedling emergence and seedling growth tests were conducted in the organic horizon of five boreal soils. Few differences in herbicide bioavailability between soils were detected. Triclopyr limited growth of A. millefolium, C. angustifolium and standard test species Calamagrostis canadensis at low levels (most IC estimates between 2-20 µg g). For imazapyr, IC estimates could not be calculated as there was >75% inhibition of endpoints at the lowest doses of ~2 µg g. A foliar application of triclopyr or imazapyr for woody species control would likely cause significant damage to boreal non-target plants. The high sensitivity of both species to herbicide residues in soil indicates long term impacts are dependent on herbicide degradation rates in northern conditions. A. millefolium performed well and is recommended for use in toxicity testing relevant to boreal regions. [ABSTRACT FROM AUTHOR]

Seven imazapyr-tolerant mutant sugarcane plants, previously generated by in vitro mutagenesis, were studied. The imazapyr concentrations required to inhibit their acetolactate synthase (ALS basal activity) (IC50 as μmoles acetoin h-1 mg-1 protein) were 0.77 - 5.36 times greater than that of the N12 'parent'. The basal ALS activities of Mut1 and Mut6 were 1.4-fold higher than that of N12. When the mutants were sprayed with Arsenal® GEN 2 (312 and 624 g a.i. imazapyr ha-1), 2 months after field planting, and evaluated 9 months later, live stalk height and number were significantly lowest in Mut2, Mut3 and the control N12. No differences in sucrose, fibre and estimated yield were observed amongst lines in untreated plots. Mutant plants germinated and grew in soil treated with the herbicide (at the lethal dose of 1248 g a.i. ha-1). The Mut lines tested in this study offer improved options for weed control. [ABSTRACT FROM AUTHOR]

The resistance of barnyardgrass (Echinochloa crus-galli) to imidazolinone herbicides is a worldwide problem in paddy fields. A rapid diagnosis is required for the selection of adequate prevention and control practices. The objectives of this study were to develop expedite bioassays to identify the resistance to imidazolinone herbicides in barnyardgrass and to evaluate the efficacy of alternative herbicides for the post-emergence control of resistant biotypes. Three experiments were conducted to develop methods for diagnosis of resistance to imazethapyr and imazapyr + imazapic in barnyardgrass at the seed, seedling and tiller stages, and to carry out a pot experiment to determine the efficacy of six herbicides applied at post-emergence in 13 biotypes of barnyardgrass resistant to imidazolinones. The seed soaking bioassay was not able to differentiate the resistant and susceptible biotypes. The resistance of barnyardgrass to imidazolinones was effectively discriminated in the seedlings and tiller bioassays seven days after incubation at the concentrations of 0.001 and 0.0001 mM, respectively, for both imazethapyr and imazapyr + imazapic. The biotypes identified as resistant to imidazolinones showed different patterns of susceptibility to penoxsulam, bispyribac-sodium and pyrazosulfuron-ethyl, and were all controlled with profoxydim and cyhalofop-butyl. The seedling and tiller bioassays are effective in the diagnosis of barnyardgrass resistance to imidazolinone herbicides, providing an on-season opportunity to identify the need to use alternative herbicides to be applied at post-emergence for the control of the resistant biotypes.

Abstract Open pine–grasslands are one of the most threatened ecological communities in the southeastern United States and provide essential habitat for many regionally declining bird species. While open pine–grassland forests have diminished, acreage of pine plantations has increased throughout the Southeast, in part because of the U.S. Department of Agriculture Farm Bill conservation programs. To understand whether fire and herbicide treatments would be effective in creating pine–grassland structure in plantations suitable for a suite of declining early successional and pine–grassland adapted species, we evaluated combined effects of selective herbicide and prescribed fire on plant and bird communities in thinned, mid‐rotation pine stands established under the Conservation Reserve Program (CRP) in Mississippi, USA. Within each of the 12 replicate sites, we assigned 2 paired 8.1‐ha plots to either treatment (herbicide + prescribed fire) or control in a randomized complete block design. We applied treatments during autumn and winter of 2002–2003. During 2003–2006 breeding seasons, we characterized the bird community using repeated (4–6 repetitions/yr), standardized, 10‐minute point counts from which we estimated species richness, total relative abundance, total avian conservation value, and density of select species. Managed plots exhibited reduced hardwood midstory and a greater abundance of grasses and forbs in the ground layer. Although avian species richness and total relative abundance were similar in treatment and control stands, we observed a shift in the bird community from closed‐canopy forest species to early successional and pine–grassland adapted species, many of which are experiencing population declines. We recommend thinning, hardwood midstory control, and prescribed burning within CRP pine plantations to provide habitat for a suite of regionally declining bird species. © 2012 The Wildlife Society.