With a trunk circumference of 208 inches in 2009, a height of 84.6 feet, and a spread of 110 feet (pabigtrees.com), this tree is among the top three largest White Oaks in Lancaster County, and among the top 30 White Oaks in Pennsylvania.
”The Penn Hill Oak was a young tree when the Quaker meeting house was built around 1750,” Mary Boomsma said. “I’ve heard it was there before William Penn was given Pennsylvania.”
The ISA formula for inferring the age of trees (see Special Topics: Estimating the Age of Trees) produces a figure of 331 years using the 2009 measurements; up- dating to 2018 brings the estimate to 340. Thus Boomsma’s statement is plausible: This White Oak may indeed be a Penn Tree. (King Charles II of England granted William Penn the lands of Pennsylvania in 1681, 327 years ago.)
This amazing species has an unusual tolerance for growing near Black Walnut trees whose roots exude a natural herbicide (juglone) that severely retards the growth of other plants.
