Research Projects
Community Ecology
Forest management and restoration
We are exploring best practices in forest management in northeast Ohio, and beyond. Since 2018, scientists and conservation staff at the Holden Arboretum have partnered with area scientists and land...
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Community Ecology
Global warming shifts plant phenology
We are exploring how spring phenologies are shifting with the changing climate in the Holden Arboretum’s Bole Woods. In this citizen science project, volunteers have been monitoring spring leaf out...
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Plant Physiological Ecology
Local adaptation to climate in Rhododendron minus
Plant species are distinct types which we recognize by their unique leaf and flower traits, but how do different species evolve? One way this can occur is when populations of...
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Community Ecology
Ecological integrity of forests
Global change phenomena are imminent and substantial threats to biodiversity. Such threats include invasive species, global warming, land use history, and predator decline and are often induced or exacerbated by...
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Rhododendron Conservation and Collections
Landscape plant breeding
Whether in an old growth forest or an urban street, plants benefit our physical and mental well-beings and provide countless ecosystem services. Unfortunately, not all plants are well-adapted to human...
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Soil and Microbial Ecology
Forest pathogens and tree health
When given the proper environmental conditions and susceptible hosts, pathogens can do significant damage to forests. Forest pathogens are usually microscopic and include fungi, bacteria, viruses, and invertebrates. Because they...
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Soil and Microbial Ecology
Acidic precipitation and forest health
Holden scientists received a grant from the National Science Foundation to look at how forests and soils respond to changes in acidity and soil phosphorus availability. They are manipulating soil...
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Soil and Microbial Ecology
Diversity of soil fungi and microbes
Holden is conducting research into the effects of soil physical and chemical properties on the diversity and function of soil microbes in these forests.
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Soil and Microbial Ecology
Soil ecology of urban environments
Urbanization has a substantial impact on natural ecosystems where only certain plant or animal species can thrive in areas that have high amounts of development and chemical pollution from human...
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Plant Physiological Ecology
Physiology of urban and rural trees in NE Ohio
As urban areas expand, native forest fragments are becoming surrounded by pavement and cement, exposing them to higher temperatures, elevated CO2, higher light availability and pollution. We rely on urban...
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Plant Physiological Ecology
Invasive plant species
Eastern Red Cedar (Juniperus virginiana) is a conifer species native to the Eastern United States, where this attractive tree has long-been a popular choice for landscaping. But out West in...
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Plant Physiological Ecology
Leaf and flower heat tolerance of cold hardy Rhododendron species
While Rhododendron are well-adapted to cold climates, owing to changes in climate, heat stress is becoming a major factor limiting Rhododendron production. The way plants allocate resources, i.e. the economics...
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Community Ecology
Community assembly in a warmer world
When a plant community develops anew (community assembly) the order in which species arrive can shape what that community will ultimately look like. In general, arriving early can be beneficial,...
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Rhododendron Conservation and Collections
Rhododendron collection curation
Rhododendrons have a storied history, both locally and across the world, and they have thrilled gardeners for centuries. The genus contains roughly one thousand wild-occurring species, and man-made selections number...
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