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Timothy B. Harrington - One of the best experts on this subject based on the ideXlab platform.
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effects of forest harvesting logging debris and herbicides on the composition diversity and assembly of a western washington usa plant community
Forest Ecology and Management, 2018Co-Authors: David H Peter, Timothy B. HarringtonAbstract:Abstract We examined plant community organization over the first five growing seasons after clearcut harvesting with retention of two levels of logging debris (light and heavy) and application of four vegetation control treatments (non-sprayed control, aminopyralid (A), triclopyr (T), and A + T). Our study site was 44 km northwest of Olympia, WA., USA, and before forest harvesting it was dominated by Pseudotsuga menziesii. We used a randomized split plot experimental design replicated in 6 blocks (each debris-treatment main plot had four herbicide-treatment split plots). We estimated percent canopy cover by species before forest harvesting and in post-harvest seasons 1–3 and 5 on 100 m2 plots centered in each split plot. We analyzed species composition and diversity and report the response of 10 species groups and several major species to the treatments over five seasons. We used ANOVA to examine annual treatment effects on abundance of major species and species groups as well as ordination and graphical methods to examine succession. Abundance of ruderal species, especially exotics and graminoids, was lower but abundance of native woody shrubs and vines was higher in heavy debris than in light debris. The vines developed higher cover in heavy debris where they used debris as a scaffold to gain a competitive advantage over other species. Heavy debris controlled Cytisus scoparius better than the herbicide treatments. Triclopyr reduced woody dicot, vine and native herb covers, while aminopyralid reduced these groups and Cytisus scoparius, but aminopyralid had less effect on total canopy cover. The combination herbicide treatment reduced woody dicots, vines and Cytisus scoparius, and had the biggest impact on total canopy cover. By year 5 there was little difference in total canopy cover among the herbicide treatments; however, for some species, both debris and herbicide treatment effects were still apparent. The ordination indicated that, by the fifth season, the floristic characteristics distinguishing the debris treatments were still distinct, but not for the herbicide treatments. We conclude that heavy debris is a viable treatment alternative to prevent aggressive exotic species from competing with planted conifers and the native plant community on edaphically dry western Washington sites.
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Synthetic Auxin Herbicides Control Germinating Scotch Broom (Cytisus scoparius)
Weed Technology, 2014Co-Authors: Timothy B. HarringtonAbstract:Abstract Scotch broom is a large, nonnative shrub that has invaded forests and grasslands in 27 U.S. states. Without treatment, Scotch broom's persistent seedbank ensures a continuing source of regeneration after soil disturbance. In growth chamber studies, five rates of three synthetic auxin herbicides, aminocyclopyrachlor (AC), aminopyralid (AP), and clopyralid (CP), were compared for PRE control of Scotch broom. Cumulative 90-d emergence, mortality, and biomass of seedlings did not vary among herbicides, averaging 42% of seeds sown, 75% of emerged seedlings, and 9 mg seedling−1 for treated containers, respectively, versus 46%, 17%, and 26 mg seedling−1 for nontreated containers. Low rates of each herbicide (
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synthetic auxin herbicides control germinating scotch broom Cytisus scoparius
Weed Technology, 2014Co-Authors: Timothy B. HarringtonAbstract:Abstract Scotch broom is a large, nonnative shrub that has invaded forests and grasslands in 27 U.S. states. Without treatment, Scotch broom's persistent seedbank ensures a continuing source of regeneration after soil disturbance. In growth chamber studies, five rates of three synthetic auxin herbicides, aminocyclopyrachlor (AC), aminopyralid (AP), and clopyralid (CP), were compared for PRE control of Scotch broom. Cumulative 90-d emergence, mortality, and biomass of seedlings did not vary among herbicides, averaging 42% of seeds sown, 75% of emerged seedlings, and 9 mg seedling−1 for treated containers, respectively, versus 46%, 17%, and 26 mg seedling−1 for nontreated containers. Low rates of each herbicide (< 50% of the maximum labeled rate [MLR]) provided 60 to 80% control, whereas 100% MLR provided 69 to 89% control. Although the herbicides differed in cost per unit seedling mortality (AP < CP < AC), each demonstrated strong potential as a viable treatment for PRE control of Scotch broom. Nomenclatur...
Isao Kubo - One of the best experts on this subject based on the ideXlab platform.
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2 3 dehydro 10 oxo α isosparteine in uresiphita reversalis larvae fed on Cytisus monspessulanus leaves
Phytochemistry, 2002Co-Authors: Kenichi Nihei, Kozo Shibata, Isao KuboAbstract:Abstract Quinolizidine alkaloids, found in the leaves of Cytisus monspessulanus L. (Leguminosae), were characterized in the cuticle of larvae of the pyralid moth Uresiphita reversalis (Lepidoptera: Pyralidae) when the latter were fed on this weed. By GC–MS analysis of the methanolic extracts of the cuticle, four quinolizidine alkaloids, N -methylcytisine, cytisine, aphylline and anagyrine, were identified as possible defense substances. In addition, the quinolizidine alkaloid, (+)-2,3-dehydro-10-oxo-α-isosparteine was characterized in both the insect and host plant.
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(+)-2,3-Dehydro-10-oxo-α-isosparteine in Uresiphita reversalis larvae fed on Cytisus monspessulanus leaves
Phytochemistry, 2002Co-Authors: Kenichi Nihei, Kozo Shibata, Isao KuboAbstract:Abstract Quinolizidine alkaloids, found in the leaves of Cytisus monspessulanus L. (Leguminosae), were characterized in the cuticle of larvae of the pyralid moth Uresiphita reversalis (Lepidoptera: Pyralidae) when the latter were fed on this weed. By GC–MS analysis of the methanolic extracts of the cuticle, four quinolizidine alkaloids, N -methylcytisine, cytisine, aphylline and anagyrine, were identified as possible defense substances. In addition, the quinolizidine alkaloid, (+)-2,3-dehydro-10-oxo-α-isosparteine was characterized in both the insect and host plant.
Ingrid M. Parker - One of the best experts on this subject based on the ideXlab platform.
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Direct and indirect effects of allelopathy in the soil legacy of an exotic plant invasion
Plant Ecology, 2012Co-Authors: Sara Grove, Karen A. Haubensak, Ingrid M. ParkerAbstract:Invasive species may leave behind legacies that persist even after removal, inhibiting subsequent restoration efforts. We examined the soil legacy of Cytisus scoparius , a nitrogen-fixing, putatively allelopathic shrub invading the western US. We tested the hypothesis that allelopathy plays a critical role in the depressive effect of Cytisus on the key native Douglas-fir, both directly on tree growth and indirectly via effects on its ectomycorrhizal fungi (EMF). In a greenhouse factorial experiment, we used activated carbon to inhibit Cytisus -produced allelochemicals and sucrose to reduce elevated nitrogen (N). We found that: (1) Cytisus -invaded soils depressed Douglas-fir growth compared to uninvaded forest soils. The effect of adding Cytisus litter was positive (possibly reflecting an N fertilization effect) only in the presence of activated carbon, providing evidence for a role of allelopathic compounds. Activated carbon did not increase growth in the absence of Cytisus litter. Finally, sucrose addition provided weak support for a nitrogen effect of Cytisus litter. (2) Seedlings grown in Cytisus soils had lower EMF abundance compared to those in uninvaded forest soils. In forest soil from one site, adding Cytisus litter also decreased EMF abundance. Douglas-fir growth increased significantly with EMF across sites and soils suggesting that changes in EMF were linked to tree growth. The fungal taxon Cenococcum geophilum was significantly depressed in Cytisus soils compared to forest soils, while Rhizopogon rogersii abundance was similar across soil types. These results together suggest an overall negative effect of Cytisus on the growth of a dominant native tree and its fungal symbionts. Our study suggests how the role of allelopathy in ecological restoration may play out on two time scales: through immediate, direct impacts on native plants as well as through long-term, persistent impacts mediated by the collapse or transformation of microbial communities.
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soil changes accompanying invasion of the exotic shrub Cytisus scoparius in glacial outwash prairies of western washington usa
Plant Ecology, 2004Co-Authors: Karen A. Haubensak, Ingrid M. ParkerAbstract:Shrub encroachment of grassland is a global phenomenon that can cause substantial and rapid changes in soil nutrient levels and distribution. If the woody plants in question also have the capacity to fix nitrogen (N), the effects on soil nutrients may potentially be large. Cytisus scoparius L. Link (Scotch broom) is an introduced leguminous shrub from the Mediterranean region that colonizes open grasslands. We measured several properties of the surface soil (0-10 cm depth) across advancing fronts of Cytisus to assess changes in soil fertility associated with invasion in western Washington state (USA). Both total soil C and N increased (1.8% and 6.5%, respectively), resulting in a decrease in C to N ratio of 22.5 in uninvaded soils to 21.5 inside Cytisus patches. δ15N signature of surface soil did not clearly demonstrate a signal of N2-fixation across the Cytisus gradient. On the other hand, seven-day laboratory aerobic incubations demonstrated 3 and 2.4 times greater mineralization and nitrification rate, respectively, in Cytisus soils compared to uninvaded soils. Despite this increase in N availability, bioassay plants (Achillea millefolium) grown in uninvaded soils in the greenhouse were ∼ 30% larger than those grown in Cytisus-invaded soils, suggesting that Cytisus may have inhibitory effects on some plants growing in invaded soils. These results suggest that the impact of Cytisus invasion on grassland plant communities may be influenced or tempered by chemical or microbial effects on the soil other than simply increased labile N.
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invasion dynamics of Cytisus scoparius a matrix model approach
Ecological Applications, 2000Co-Authors: Ingrid M. ParkerAbstract:It is at the level of population dynamics that an invasion either fails or succeeds. By elucidating patterns of variation in population growth rates or demographic rates, it is possible to forge a connection between quantitative field data and theoretical ideas about invasiveness, invasibility, and rates of spread. Demographic models also provide a tool to guide control strategies for invasive pests. Here I report the results of a demographic study of Cytisus scoparius, an exotic shrub on the west coast of North America. I used matrix population models to describe demographic patterns in six populations (three in prairies and three in urban fields) and across advancing stages of invasion. At the edge of the invading front, all populations showed finite rates of increase (λ) >1; however, prairie populations were increasing much more rapidly than urban ones. While many individual vital rates differed between prairie and urban populations, Life Table Response Analysis revealed that seedling establishment mad...
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POLLINATOR LIMITATION OF Cytisus SCOPARIUS (SCOTCH BROOM), AN INVASIVE EXOTIC SHRUB
Ecology, 1997Co-Authors: Ingrid M. ParkerAbstract:Introductions of exotic species provide unique opportunities to study the demographic significance of species interactions, but as yet there is little information on how mutualistic interactions affect the invasion process. A shortage of mutualists could potentially limit the rate of population growth for an invading species. The introduced shrub Cytisus scoparius (Scotch broom, Leguminosae) is a pest plant on the west coast of North America. It produces flowers that are “tripped” open when pollinated and has a nearly obligatory relationship with resident bumble bees and honey bees. Experiments in the state of Washington showed that
Kenichi Nihei - One of the best experts on this subject based on the ideXlab platform.
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2 3 dehydro 10 oxo α isosparteine in uresiphita reversalis larvae fed on Cytisus monspessulanus leaves
Phytochemistry, 2002Co-Authors: Kenichi Nihei, Kozo Shibata, Isao KuboAbstract:Abstract Quinolizidine alkaloids, found in the leaves of Cytisus monspessulanus L. (Leguminosae), were characterized in the cuticle of larvae of the pyralid moth Uresiphita reversalis (Lepidoptera: Pyralidae) when the latter were fed on this weed. By GC–MS analysis of the methanolic extracts of the cuticle, four quinolizidine alkaloids, N -methylcytisine, cytisine, aphylline and anagyrine, were identified as possible defense substances. In addition, the quinolizidine alkaloid, (+)-2,3-dehydro-10-oxo-α-isosparteine was characterized in both the insect and host plant.
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(+)-2,3-Dehydro-10-oxo-α-isosparteine in Uresiphita reversalis larvae fed on Cytisus monspessulanus leaves
Phytochemistry, 2002Co-Authors: Kenichi Nihei, Kozo Shibata, Isao KuboAbstract:Abstract Quinolizidine alkaloids, found in the leaves of Cytisus monspessulanus L. (Leguminosae), were characterized in the cuticle of larvae of the pyralid moth Uresiphita reversalis (Lepidoptera: Pyralidae) when the latter were fed on this weed. By GC–MS analysis of the methanolic extracts of the cuticle, four quinolizidine alkaloids, N -methylcytisine, cytisine, aphylline and anagyrine, were identified as possible defense substances. In addition, the quinolizidine alkaloid, (+)-2,3-dehydro-10-oxo-α-isosparteine was characterized in both the insect and host plant.
Othmane Merah - One of the best experts on this subject based on the ideXlab platform.
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effect of phenological stages on essential oil composition of Cytisus triflorus l her
Journal of King Saud University - Science, 2020Co-Authors: Selma Daghbouche, Imene Ammar, Dorsaf Moalla Rekik, Zahreddine Djazouli, Bachar Zebib, Othmane MerahAbstract:Abstract Essential oil is widely used in perfumery, cosmetic, pharmaceutic and food industries. The economics of essential oil production depend on both parameters; the cultivation of aromatic herbs and the extraction of oils from these herbs. This study investigated for the first time the variation in essential oil and composition of Cytisus triflorus L'Her plant at different growth times (vegetative, flowering and fruiting stages). Essential oil was extracted by hydro-distillation. The flowering stage show the highest essential oil yield (0.61 ± 0.02 mL/100 g) compared to those of vegetative (0.41 ± 0.01 mL/100 g) and fruiting (0.17 ± 0.01 mL/100 g) stages. For all growth stages, Thirty-eight compounds were identified, representing 93.21% – 95.47% of the oil, where the main components were β-linalool (28.28 to 38.04%), Geraniol (19.82 to 27.73%), Retinal (4.33 to 9.26%), p-Mentha-1,4-dien-8-ol (2.09 to 4.08%), γ-Terpinene (1.27 to 4.86%) and Eugenol (2.07 to 2.28%). Monoterpene hydrocarbons were detected at higher level at flowering compared to vegetative and fruiting stages. In contrast, aldehydes were noted at higher percentage at vegetative stage. This study highlighted difference in content and composition of essential oil in Cytisus triflorus L'Her during growth stages. Flowering was the interesting stage for harvesting and with more specific composition in essential oil.
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Effect of phenological stages on essential oil composition of Cytisus triflorus L’Her
Journal of King Saud University - Science, 2020Co-Authors: Selma Daghbouche, Imene Ammar, Dorsaf Moalla Rekik, Zahreddine Djazouli, Bachar Zebib, Othmane MerahAbstract:Abstract Essential oil is widely used in perfumery, cosmetic, pharmaceutic and food industries. The economics of essential oil production depend on both parameters; the cultivation of aromatic herbs and the extraction of oils from these herbs. This study investigated for the first time the variation in essential oil and composition of Cytisus triflorus L'Her plant at different growth times (vegetative, flowering and fruiting stages). Essential oil was extracted by hydro-distillation. The flowering stage show the highest essential oil yield (0.61 ± 0.02 mL/100 g) compared to those of vegetative (0.41 ± 0.01 mL/100 g) and fruiting (0.17 ± 0.01 mL/100 g) stages. For all growth stages, Thirty-eight compounds were identified, representing 93.21% – 95.47% of the oil, where the main components were β-linalool (28.28 to 38.04%), Geraniol (19.82 to 27.73%), Retinal (4.33 to 9.26%), p-Mentha-1,4-dien-8-ol (2.09 to 4.08%), γ-Terpinene (1.27 to 4.86%) and Eugenol (2.07 to 2.28%). Monoterpene hydrocarbons were detected at higher level at flowering compared to vegetative and fruiting stages. In contrast, aldehydes were noted at higher percentage at vegetative stage. This study highlighted difference in content and composition of essential oil in Cytisus triflorus L'Her during growth stages. Flowering was the interesting stage for harvesting and with more specific composition in essential oil.
