“We are extremely fortunate to have this woodlot on the arboretum property,” Steiner adds. “It has escaped complete destruction— and perhaps even partial cutting— since the arrival of the first settlers to this area, and that is very unusual for this kind of forest.”

Grinstead has mapped trails and features throughout the woodlot (including the 12.5 acres owned by the borough of State College). His inventory of the vegetation includes a very detailed record of the size, age, and condition of overstory trees. According to his calculations, there are 1,009 trees of more than 15 inches in diameter (at breast height, 4.5 feet) on the university- owned section of the Hartley Wood.

Grinstead has “cored” 200 trees to determine their ages and examined the cross-section of a massive white oak that died in 2000. The slice revealed that the tree had germinated in approximately 1673.

Grinstead's assessment of today's conditions indicates that exotic shrubs, such as multiflora rose, bush honeysuckle, privet, and garlic mustard, have become prevalent and troublesome in the Hartley Wood and should be removed. “We need to educate people about the ecologically destructive potential of invasive plants,” he says. “Unfortunately, some of the traits that make exotics good ornamental plants also make them good invaders of native habitats.”

—Jeff Mulhollem