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Biodiversity

Biodiversity is the variety of life forms found within an ecosystem and is often used as an indicator of environmental health. The American forests form a variety of environments across the country. Most are made up of different species and ages of trees. Managed forests are interspersed with natural forests throughout the landscape while rivers, streams, and wetland areas meander through the forests. These diverse conditions provide the many unique habitats supporting different plant and animal species across the country. Managed forests, which can include planted trees are highly productive and acre by acre produce more wood than any other forest type. A distinguishing feature of planted forests is their relative uniformity — trees are usually evenly spaced and similar in size. When newly planted, this manicured appearance can make the forest resemble agricultural fields. While newly planted forests might look like agricultural fields, they are vastly different in how they function ecologically and how they are managed.

Ecological inquiries commonly start with habitat, which is greatly influenced by vegetation. As forest stands develop, the abundance and expression of tree, shrub, and herbaceous species fluctuate through time. For instance, planted forests typically comprise many plant species during their early and later years. In the middle years, planted forests generally contain fewer plants. This condition of low vegetation diversity also occurs in naturally regenerated forest stands as they develop. Low levels of vegetation diversity in older forests can often be traced to former land uses. Managed forests help these areas recover and provide new habitats. In time, with proper management even highly disturbed sites will recover.

Wildlife is typically used as indicators of habitat quality. Dozens of collaborative research projects have consistently shown that planted pine forests provide habitat (cover, reproductive areas, food, and water) for a wide variety of non-game (songbirds, reptiles, amphibians) and game species (deer, turkey, quail, and rabbit), Over 200 different bird species, including some threatened species have been found in recovered forest lands in the eastern U.S. Bird census data from land in North Carolina suggest that managed forests appear to be supporting relatively large numbers of these birds. These birds favor low-growing, "shrub-scrub" habitat, a condition common to young planted forests. Game species are also thriving on newly recovered lands as evidenced by the high competition for access rights throughout the south for hunting and recreational purposes.

In the United States, about 70% of productive forests are privately owned. and more than 80% of these forests are owned by about 10 million families. Many of the productive forests in the United States, particularly in the Southeast, have been established on land that was cleared for agriculture and human settlement beginning in the 1600's. In the mid-20th century, the government provided incentives to property owners to plant land with trees. The Southeast provides an important source of fiber for America. Likewise, the need for this fiber provides an important reason for the continued stewardship of these forests.

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