Pennsylvania Timber Production History

According to the passage, some of the problems affecting the forests in the state include: insects, diseases, and poor harvesting practices that are driving tree species composition change, leading to less desirable tree species becoming more common, invasive exotic plants outcompeting native trees and plants, and competing native plants like ferns, spicebush, and mountain laurel increasing in the forest understories.

The passage states that all of the oak species are much less common in the forests.

The passage provides examples of invasive exotic plants such as multiflora rose, bush honeysuckle, ailanthus (aka, tree of heaven), autumn olive, and garlic mustard.

According to the passage, the poorly conceived harvesting practices, such as selective cutting and diameter limit cutting, are shifting the overstory species composition, removing desirable seed sources, leaving poorer quality trees, and generally reducing the forest's economic and ecological values.

The passage states that the use of carefully applied science-based forestry practices is needed to restore forest health and provide future value to those landowners who will own and manage the forests tomorrow.

The passage mentions that less desirable tree species such as red maple, black birch, and black gum are becoming more common in the forests.

The first sawmill was established by Swedish settlers in Philadelphia in 1662.

About 90 percent of the province was covered by forests.

Penn recommended that "care be taken to leave one acre of trees for every five acres cleared."

The peak of land clearing was in the 1890s, when about two-thirds of the state was cleared.

During this period of forest exploitation, the forest-dependent industries such as leather tanning, wood chemical manufacturing, charcoaling, and sawmilling collapsed and economic conditions led to farmland abandonment.

Today, Pennsylvania's hardwood forests contain world-class oak, maple, and cherry, and forest inventories suggest that the state has more tree volume growing than it has had in more than 100 years.