Fraxinus americana (White Ash)
3. Walk away from Galvin Hall towards the street in front of the building. At the steps down to the street are two nice specimens of: Fraxinus americana (White ash). One tree is male and the other is female, but you can only tell which one is which in the early spring when they bear their unisexual flowers. Leaves are opposite and compound, with 7-9 leaflets. The bark of mature trees is sometimes an ash-gray color (the basis of the common name), has obvious longitudinal ridges and furrows, and is often partially covered with pale green lichens. Lichens are symbiotic associations of algae and fungi. White ash is a very common tree in the campus quadrangle and natural area.