The Holden Arboretum owns over 3,600 acres. Of that, approximately 3,100 acres are natural areas. Approximately 85 percent of Holden’s natural areas are woodland; 12 percent meadows; and the remaining three percent are wetlands, streams, rivers, ponds and lakes.
Blessed with abundant natural resources, which range from the unique land itself to the hundreds of native plant, animal and insect species that live within these lands, Holden adopted a strategic plan for conservation in 2006 in order to establish goals and outline the types of active management that would take place in Holden natural areas.
The goal is to manage Holden's natural areas for the purpose of sustaining or increasing current levels of native biodiversity, with an emphasis on plants.
In general terms, biodiversity is the variety and variability among native living organisms and the natural ecosystems in which they occur. Biodiversity encompasses the differences between and within; ecosystems, genera, and the genetic or molecular diversity of any species. Holden’s natural areas hundreds of plants, animals, insects and birds co-exist and combine to create the diverse landscape we call The Holden Arboretum.
We think of biodiversity at three main levels:
Active natural area management includes any activity designed to remove or retard negative influences on an ecosystem to the extent possible, including but not limited to, the impact caused by invasive plant species, invasive pests and pathogens, and white-tailed deer.
The Holden Arboretum is all about plants with a special emphasis on woody plants. Staff expertise is plants. Plants create the number of vertical niches available and utilized in the plant community. Vertical niches exist within all the layers of vegetation that naturally occur within plant communities. A great diversity of species inhabit and utilize the available vertical niches for nesting, food or cover. The greater the number of vertical niches utilized, the greater the natural biodiversity.