Wild Plant Sanctuaries
Threats to Native Plants in Pennsylvania
Global biodiversity is crumbling at an alarming rate. Conditions on this planet are changing too fast for many organisms to adapt, steadily pushing Earth’s precious biota over the edge of extinction. With our natural heritage threatened and our ecosystem services jeopardized, Pennsylvanians are taking steps to guarantee the conservation of vital ecological areas. Join this movement by enrolling your property in the Wild Plant Sanctuary Program. Together, we can ensure that future generations inherit more than just a planet of weeds.
Habitat Destruction: Loss of habitat is the number one threat to native plants in Pennsylvania. Development and natural resource harvesting often lead to the complete elimination of plant communities. Furthermore, any resulting fragmented habitat is compromised by edge effects, such as changes in lighting and moisture conditions and invasive species infestations. Major causes of habitat destruction include agriculture, urban sprawl, mining, and clearcutting.
Exotic Species: Humans have a knack for transporting species around the globe, whether intentionally or by accident. Lacking the checks and balances found in their native regions, invasive plants have overrun much of Pennsylvania, outcompeting native plants and shattering the complex web of life which depends on healthy native plant communities. To make matters worse, exotic pests and diseases, often arriving as stowaways on horticultural curiosities, are devastating many of our native trees.
Deer Overbrowsing: Following extensive deforestation and enactment of hunting regulations in the early twentieth century, deer populations expanded rapidly. An increase in fragmented edge habitat and the elimination of top predators have contributed greatly to this problem. Deer overbrowsing ravages understory vegetation, extirpating species from vast swaths of forest, altering species composition, and suppressing tree regeneration.
Altered Disturbance Regimes: The human urge to control nature has thrown a wrench in the delicate disturbance cycles that many ecological communities depend on for persistence. Dams and bank erosion have deprived floodplains of life-sustaining floods while upland regions are suffocating under decades of fire suppression. Many plant species are well adapted to these destructive natural events and cannot survive long without them.
Pollution: The advent of the industrial, green, and technological revolutions have pumped so many foreign substances into our ecosystems that it is rather difficult to interpret the full and synergistic environmental effects of this pervasive chemical soup. The leaching of nutrients and acidification of soil pH by acid rain, the eutrophication of land and water by fertilizer applications, and the bleeding of silt into our waterways by erosive forces are all examples of pollution.
Collecting: Wild plants are appreciated worldwide as important sources of medicine and rare objects of beauty. However, because many native plants are in decline, unmitigated collection threatens to extirpate whole populations. In Pennsylvania, American ginseng and goldenseal are harvested for medicinal use and must be regulated to prevent population loss. Many native plants, especially orchids, are hunted by unscrupulous collectors due to their scarcity and charm.
Global Warming: Most scientists agree that the release of carbon dioxide and other greenhouse gases resulting from human activities is causing a steady increase in global temperatures. Already under pressure from many other angles, native plants must now deal with temperature and moisture fluctuations. Many populations will likely have difficulty moving fast enough to keep pace with global changes, especially when migratory routes are blocked by human development.