Learn about some of the trees that are part of the large campus-wide Allegheny Arboretum.
Black Oak
Black Oak — Quercus velutina
This tree often hybridizes with red oak. Tannins from the bark were used to tan leather and make yellow dye.
Blue Spruce
Blue Spruce — Picea pungens
Native to the Rocky Mountains. This is a popular ornamental and Christmas tree. The needles are four-sided and when bruised give off an odor. The needles range in color from a blue-green to a pale yellowish-green.
Red Oak
Red Oak — Quercus rubra
This is the fastest growing of all oaks. Acorns mature at the end of their second growing season, drop in the fall and germinate the following spring.
Honey Locust
Honey Locust — Gliditsia triacanthos
Also know as Sweet Locust or Thorny Locust. Has spines from 2- to 8-inches long. Bows were made from the branches of this tree.
Red Maple
Red Maple — Acer rubrum
Grows on a wider range of soil types, moisture, pH and elevation than any other forest tree in North America. At all seasons of year, this tree has something red about it. Also called soft maple because the wood is soft (opposed to hard maple-sugar maple).
Sugar Maple
Sugar Maple — Acer saccharum
Sap collected during late winter and early spring is boiled down to make syrup and sugar. The wood is hard, tough, close-grained, and makes excellent hardwood floors.
White Oak
White Oak — Quercus alba
The wood is extremely strong, hard, and heavy. It is the most valuable of all oak woods. Because the pores of the wood are plugged with woody cells (tyloses), liquids cannot seep through them and the wood has been used for barrels. Lacking a strong tannin defense, white oak acorns germinate quickly after they fall.
Ohio Buckeye
Ohio Buckeye — Aesculus glabra
Also called Fetid or Stinking Buckeye, because of its twigs and leaves, when broken, release a foul smell. The dark brown seeds, which resemble the eye of a deer, account for the buckeye name. The plant contains a narcotic alkaloid that is poisonous. Plant parts were used by settlers to stun fish for easy catching.
Tulip Tree
Tulip Tree — Lirodendron tulipfera
Also known as Tulip Poplar or Yellow Poplar. However, it is unrelated to the poplars. The two-inch yellow-green flowers form in May and June, and resemble tulips and the water lily. Another name for this tree, “canoe wood,” comes from its use by Native Americans. Supposedly, Daniel Boone floated his family down the Ohio River in such a canoe.
Eastern Hemlock
Eastern Hemlock — Tsuga canadensis
The state tree of Pennsylvania. Rich in tannic acid, the bark was used to cure leather in the late 1800s and early 1900s. Needles have two white lines on their lower surface.
Norway Maple
Norway Maple — Acer platanoides
Introduced from Europe as a shade tree, this species has spread widely. The leafstalks (petiole), when broken, exude a milky sap. Tolerant to pollution.
Flowering Dogwood
Flowering Dogwood — Cornus florida
The four white “petals” are actually bracts that cover the developing small flowers located where the bracts intersect. The common name comes from the German word dag, meaning a skewer to hold meat, and likely this hard wood was used for this task. This species is under attack by the fungus Discula from Asia.
American Beech
American Beech — Fagus grandifolia
The thin, smooth, pale gray bark is a distinctive trait of this tree. Markings made by wild animals and humans remain on the bark. Our word book derives from the Anglo-Saxon boc, meaning letter, which in turn comes from beece, for beech. The leaves can remain on the tree during winter.
Douglas Fir
Douglas Fir — Pseudotsuga menziesii
Native to the western side of the Rocky Mountains. The genus name comes from its resemblance to the hemlocks. Cones are unique by the presence of elongated tri-toothed bracts that extend beyond the scales.
Dawn Redwood
Dawn Redwood — Metasequoia glyptostroboides
Thought to be extinct, but “rediscovered” in northern China in the late 1940s, it is often referred to as a living fossil. This deciduous conifer grew throughout North America and Europe before the glaciers wiped them out.
American Sycamore
American Sycamore — Platanus occidentalis
The largest tree in eastern North America. It can live 500-600 years. In the wild, look for sycamores along streams, rivers and lakes. The tree is monecious. The female flowers will develop into a composite spherical fruits about one inch in diameter.
American Elm
American Elm — Ulmus americana
These are becoming rare because of the Asian fungus, Dutch Elm disease, which arrived in the 1930s and has killed most of these trees. When mature, it is characterized by its vase shape. This "Survivor Tree" was taken from a cutting from the Oklahoma City tree that survived the bombing of 1995.
Tamarack
Tamarack — Larix laricina
Also called American Larch, it is the only native, deciduous, needle-leaved tree. This trait is believed to have developed when the ancient species lived near the Artic Circle and evolved to drop their needles during the long days without light.
Fraser Fir
Fraser Fir — Abies fraseri
It is named after Scottish botanist John Fraser (1750-1811), who collected plants in the Appalachian Mountains. It has been severely damaged by a non-native insect, the balsam woolly adelgid.
White Pine
White Pine — Pinus strobus
Named for its pale wood, it was the most highly sought logging tree between the 1700s and early 1900s. It is the only pine to hold its needles in bundles of five.
Black Gum
Black Gum — Nyssa sylvatica
Also known as Sour Gum because of its bad-tasting fruit. In the south, it is called Tupelo, from the Creek words ito opilwa, meaning "swamp tree." Nyssa comes from Greek, denoting a “water nymph,” and sylvatica means “of the forest.”
Paper Birch
Paper Birch — Betula papyrifa
The most widely distributed birch in North America. It is used for birch-bark canoes. Its sap can be made into syrup.
Maidenhair Tree
Maidenhair Tree — Ginkgo biloba
Species has both male and female trees (dioecious). Females produce an edible seed that has a pungent odor when ripe. A diagnostic trait is its fan-shaped leaves.
Cucumber Tree
Cucumber Tree — Magnolia acuminata
The name magnolia commemorates the French botanist Pierre Magnol, who died in 1715. The compound fruit — oblong, curved, knobby, and greenish — give the tree its name.
Eastern Redbud
Eastern Redbud — Cercis canadensis
Also called "Judas tree." The bright violet-purple flowers form in early spring before the leaves appear. The fruit is a pod 2-3 inches long which contains 4-10 bean-like seeds.