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POPULATION LOSS OF GOLDENSEAL, HYDRASTIS CANADENSIS L., (RANUNCULACEAE), IN OHIOMulligan, Margaret R. 17 October 2003 (has links)
No description available.
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Quantifying Impacts of Deer Browsing and Mitigation Efforts on Hardwood Forest RegenerationCaleb H Redick (8067956) 03 December 2019 (has links)
<p>Due to overpopulation and
resource-poor habitat structure, deer threaten the<a>
future of oak and other browse-sensitive species in hardwood forests. </a>Appropriate
tools must be used to ensure desirable, diverse, and ecologically stable
regeneration of future forests and the sustainability of native plant
communities. We performed two experiments and a review to examine the
effectiveness of available methods for managing browse of hardwood seedlings
and to discover how these interact with each other and other silvicultural
methods. First, we examined how fencing interacts with controlled-release
fertilization, seed source (genetically select and non-select), and site type
(afforested and reforested sites) to enhance the regeneration of planted
northern red oak (<i>Quercus rubra </i>L.),
white oak (<i>Quercus alba</i>), black
cherry (<i>Prunus serotina</i>), and black
walnut (<i>Juglans nigra</i>) at five sites in Indiana. Fencing
proved to be the greatest determinant of seedling growth, survival, and
quality. Fertilizer enhanced the early growth of white oak and black cherry, though
for black cherry this occurred only inside fences. Select seed sources grew
better and showed greater quality; however, the survival of select seedlings
was limited by deer browse in absence of fences. Trees at afforested sites had lower survival if left non-fenced. Secondly, we also investigated how fencing and
invasive shrub removal affected natural regeneration, species richness, and
ground-layer plant cover under closed-canopy forests. Honeysuckle (<i>Lonicera maackii</i>)
removal had a variable effect depending on species and site. Positive effects were most common for shade-intolerant species, while negative effects occurred for a few shade-tolerant species at some sites. Deer fencing had a positive effect on
cherry and hackberry seedling density, and a negative effect on elm seedling
density. Honeysuckle and deer fencing interacted antagonistically in some
instances. Fencing without honeysuckle removal resulted in lower elm abundance and herbaceous-layer cover. In the densest invasions, leaving honeysuckle intact
resulted in a complete lack of recruitment into the sapling layer. Our experiment suggests that invasive shrub removal and fencing be done together. Finally,
we synthesized the existing literature on browse management options for
hardwood regeneration to evaluate their relative effectiveness. Fences, tree shelters, repellents, facilitation
by neighboring plants, deer population control, timber harvest, and slash all had positive
effects on height growth of regenerating seedlings under deer browse pressure. Fences
were more effective at reducing browse than repellents, while fertilizers
increased browse and had no effects on growth. </p>
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