Browsing by Author "Niemiera, Alexander X."

Now showing 1 - 20 of 293
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    American (Fagus grandifolia) and European (Fagus sylvatica) Beeches
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2018-10-04)
    Provides information about the physical features, growth requirements, and landscaping functions of American Beech (Fagus grandifolia) and European Beech (Fagus sylvatica)
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    American (Fagus grandifolia) and European (Fagus sylvatica) Beeches
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2012-02-12)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the American and European Beeches.
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    American Beautyberry
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2009-05-01)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the American Beautyberry.
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    American Beautyberry (Callicarpa americana)
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2018-10-10)
    Provides information about the physical characteristics, growth requirements, and landscape functions for American Beautyberry, Callicarpa americana.
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    American Hornbeam, Carpinus caroliniana
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2012-02-12)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the American Hornbeam.
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    American Hornbeam, Carpinus caroliniana
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2018-10-04)
    Provides information about the physical features, growth requirements, and landscaping functions of American Hornbeam, Carpinus caroliniana
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    American Yellowood
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2009-05-01)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the Yellowwood.
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    American Yellowwood (Cladrastis kentukea (prior name C. lutea))
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2018-10-10)
    Provides information about the physical characteristics, growth requirements, and landscape functions for American Yellowwood, Cladrastis kentukea.
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    Austrian Pine (Pinus nigra)
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2018-10-26)
    Provides information about the physical characteristics, growth requirements, and landscape functions for Austrian Pine, Pinus nigra.
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    Austrian Pine, Pinus nigra
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2010-11-03)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the Austrian Pine.
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    Basis for Selectivity of Isoxaben in Ajuga (Ajuga reptans), Wintercreeper (Euonymus fortunie), and Dwarf Burning Bush (Euonymus alatus 'Compacta')
    Salihu, Sydha (Virginia Tech, 1997-01-05)
    Isoxaben is a preemergence herbicide used for broadleaf weed control in turf and ornamentals. Although isoxaben can be used on a number of ornamentals, certain species are injured by isoxaben applications. The objectives of this research were: a) to evaluate the tolerance of ajuga, wintercreeper and dwarf burning bush to isoxaben applications, b) to compare the absorption, translocation and metabolism of isoxaben following root and shoot application in these ornamentals, and c) to examine the effect of isoxaben on glucose incorporation in the roots of these species. Greenhouse and lathhouse studies demonstrated that ajuga was the most sensitive species compared to wintercreeper and dwarf burning bush following root and shoot exposure to isoxaben at 0.84, 1.69 and 3.39 kg ai/ha. Following root and shoot application, isoxaben at 3.39 kg/ha caused approximately 50% shoot injury in ajuga at 2 months after treatment compared to approximately 30% in dwarf burning bush in sand culture. Wintercreeper was not visually injured by any isoxaben rate. Isoxaben at 3.39 kg/ha reduced wintercreeper root weight by 15% following root application and shoot weight by 10% following shoot application. Field studies showed that isoxaben applications made one month after bud-break caused 30 to 45% injury to dwarf burning bush. However, the plants outgrew the injury in the following year. Dwarf burning bush was not injured from applications of isoxaben made at the dormant stage or two months after the bud-break stage. Studies with root-applied radiolabeled isoxaben showed that ajuga and dwarf burning bush had absorbed 34 and 41% of the applied radioactivity, respectively, while wintercreeper had absorbed only 21% at 14 days after treatment (DAT). The percent of absorbed radioactivity which translocated was greater in ajuga (58%) and wintercreeper (50%) than in dwarf burning bush (28%). In the root extracts, metabolism of isoxaben was greater in ajuga than wintercreeper or dwarf burning bush at 3, 7 and 14 DAT. Most of the radioactivity recovered from the shoots of the three species appeared to be polar metabolites of isoxaben, possibly conjugates. In studies with shoot-applied radiolabeled isoxaben, radioactivity recovered from the treated leaf of ajuga increased from 46% of applied at 3 days to 64% at 14 days after treatment. In wintercreeper, the most tolerant species, approximately 40% of the applied radioactivity was recovered in the treated leaf at each harvest date. Radioactivity recovered from the treated leaflet increased from 45 at 3 DAT to 70% at 14 DAT in both growth stages of dwarf burning bush. Ajuga and wintercreeper metabolized isoxaben faster than dwarf burning bush. There was no difference in the metabolism of isoxaben between the two growth stages of dwarf burning bush. Incorporation of glucose in the roots of wintercreeper and dwarf burning bush was not inhibited by isoxaben (1 mM). Approximately 10% inhibition of glucose incorporation by isoxaben was observed in the roots of the sensitive species ajuga.
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    Beautybush
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2009-05-01)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the Beautybush.
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    Beautybush (Kolkwitzia amabilis)
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2018-10-12)
    Provides information about the physical characteristics, growth requirements, and landscape functions for Beautybush, Kolkwitzia amabilis.
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    Best Management Practice Use and Efficacy for the Virginia Nursery and Greenhouse Industry
    Mack, Rachel E. (Virginia Tech, 2017-01-24)
    Best management practices (BMPs) are used in the nursery and greenhouse industry to increase production efficiency, and also serve to help meet clean water limitations on contaminants entering waters such as the Chesapeake Bay Watershed. Research is lacking on which BMPs are most widely used or most efficacious for Virginia nursery and greenhouse growers. Objectives of this work were to determine BMP use, barriers to adoption, and scientific efficacy. We conducted a survey of Virginia growers to find the 1) most widely used BMPs, 2) reasons behind BMP use, and 3) any barriers to BMP adoption. Sixty growers (17%) responded to the survey. The most widely used BMPs included irrigation scheduling, integrated pest management, optimized irrigation efficiency, plant need based watering, grouping plants by water needs, on-site water capture and collection, and use of controlled-release fertilizers (CRFs). Cost was a barrier to BMP adoption, and environmental concern was a commonly reported reason for BMP use. We documented the science supporting selected water-related BMPs (grass buffer strips, CRFs, and irrigation optimization BMPs). Providing the science supporting BMP use gives growers confidence in implementing BMPs to limit water contamination, and prevent waste.
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    Bigleaf Hydrangea (Hydrangea macrophylla)
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2018-10-26)
    Provides information about the physical characteristics, growth requirements, and landscape functions for Bigleaf Hydrangea, Hydrangea macrophylla.
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    Bigleaf Hydrangea, Hydrangea macrophylla
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2010-11-03)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the Bigleaf hydrangea, hydrangea macrophylla.
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    Boxwood
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2009-05-01)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the Boxwood.
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    Bradford Callery Pear (and other cultivars) Pyrus calleryana 'Bradford'
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2010-11-03)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the Bradford callery pear.
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    Bradford Callery Pear (and other cultivars), Pyrus calleryana 'Bradford'
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2018-10-26)
    Provides information about the physical characteristics, growth requirements, and landscape functions for Bradford Callery Pear.
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    Canadian Hemlock, Tsuga canadensis
    Niemiera, Alexander X. (Virginia Cooperative Extension, 2010-11-03)
    This publication covers the physical and main features, plant needs, functions, care, and additional information for the Canadian Hemlock, Tsuga canadensis.