Like all living things, forests are susceptible to a host of potential health threats including fires, insect attacks, and diseases. In addition, invasive species often outcompete and displace natives and can be very difficult to remove from the landscape once established. While a landowner's control over these threats is limited, certain management actions will help protect their investment by minimizing their forest’s risk to damage. To maintain the health of a forest, prevention is the best approach.
Wildfire frequency and intensity vary based on location, climate, and types of trees. The northeastern United States has a temperate climate with year-round precipitation. As a result, eastern wildfires are generally low in intensity and burn fuels on the forest floor. Sometimes, these fires can actually be beneficial to the forest. Wildfire risk is greater in the Northeast during the spring and fall months when leaves are off the trees. In the spring, after the snow melts and before the new foliage emerges, the sun warms and dries last year’s fallen leaves. Similarly, in the fall the air is drier and the leaves fall and dry on the forest floor.
Pennsylvania DCNR Bureau of Forestry is responsible for protecting the Commonwealth's 17 million acres of public and private wildlands from damage by wildfire. This is accomplished by a combination of wildfire prevention, preparedness, suppression and investigation. The bureau works with fire wardens and volunteer fire departments to promote the latest advances in fire prevention and suppression.
Most people think that wildfires cause most of the tree mortality in our forests. One study of forest tree mortality factors indicates that in the United States, insects account for 41% and diseases cause 26% of the tree mortality. Put another way, insects and diseases together are responsible for killing two out of every three trees that die in our nation's forests. In general, with respect to insect and disease pests, keep in mind that healthy trees are usually much less susceptible to pest damage.
Invasive species are highly adaptable to different habitats, grow quickly or reproduce abundantly, are difficult to eradicate and can negatively impact our native species. Exotic invasive species are those plants, animals and pathogens that are not native to an area and can cause harm to the environment, to the economy and to human health. While not all exotic species are invasive, some can really do damage to our public and private lands. In their natural range, these species are limited by environmental, pest or disease conditions, keeping these species in balance within their ecosystem. When introduced into an area where these limitations are absent, some species have the ability to become invasive. While there are many different invasive species in Pennsylvania, there is a wealth of information out there to help you manage them.
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