Trees of Purdue: Blue Trail

Blue Trail

Number of trees: 29
Mileage: App. 1.75
Walking time: App. 1 hour 15 minutes

	A symbol of the state of Indiana denotes the trees that are profiled in the booklet 50 Trees of Indiana.
	A symbol of the leaf indicates that there is a link to a picture of that specific tree.
	1) River Birch—Betula nigra The river birch’s slender form graces the creek banks and lowlands of the southeastern U.S. The fluttering leaves and unique peeling orange bark make it a favorite for landscaping.
	2) American Yellowwood—Cladrastis kentukea This striking tree is known for its clusters of white, fragrant early June flowers. The smooth gray bark resembles that of beech. Yellowwood derives its name from the light yellow color of its wood.
	3) Blue Ash—Fraxinus quadrangulata Native to the United States, this ash can be identified by its square twigs and scaly bark. When exposed, the inner bark turns a shade of blue. This was used by early pioneers to dye cloth.
	4) Ohio Buckeye—Aesculus glabra The state tree of Ohio, buckeye grows along the streams of the eastern U.S. It is the first tree to leaf out in the spring and the first to drop its leaves in the fall. It produces a hard brown fruit that is highly toxic.
	5) Tuliptree—Liriodendron tulipifera The stately “yellow poplar” dwarfs many of its eastern forest companions with a height of up to 200 feet and a diameter of up to 12 feet. When constructing log cabins, pioneers favored the tuliptree for its straightness and termite resistance. Tulip is the state tree of Indiana, Kentucky, and Tennessee.
	6) Golden-rain Tree—Koelreuteria paniculata The outstanding feature of the golden-rain tree is its showy clusters of bright yellow flowers that bloom in late June or early July. The tree’s large seed pods turn an attractive bronze color in the fall.
	7) Siberian Elm—Ulmus pumila Commonly called Chinese elm, this tree is often planted for its shade because of its rapid growth rate. But this species of elm is weak-wooded, and has continuous dieback problems once it reaches a large size. This characteristic makes Siberian elm undesirable for landscaping purposes.
	8) Shingle Oak—Quercus imbricaria Shingle oak was given its name for its ability to produce a quality, durable splitshake shingle. Its leaves cling to the tree through most of the winter, creating ideal dens for squirrels.
	9) Kentucky Coffee Tree—Gymnocladus dioicus The coffee tree bears stout twigs and large, feathery, compound leaves up to three feet long. Locally scarce, the tree is used for ornamental purposes. Pioneers roasted the seeds for imitation coffee.
	10) White Oak—Quercus alba White oak is an important hardwood timber tree and the best cooperage wood in the U.S., used in the construction of buckets, pails, and barrels. This tree produces acorns that are eaten by many species of wildlife. It is the state tree of Maryland and Illinois.
	11) Amur Maple—Acer ginnala This tree is one of the more commonly planted Asian maples. Generally a large shrub or small tree exhibiting beautiful scarlet fall color, it’s also one of few maples that boast fragrant flowers.
	12) Whitespire Birch—Betula platyphylla var. japonica “Whitespire” This cultivar appears to be resistant to bronze birch borer, an insect that attacks and kills most other white-barked birches.
	13) Japanese Zelkova—Zelkova serrata An Asian cousin to our native elm, this tree has gained popularity in the U.S. because of its resistance to Dutch elm disease and its tolerance of urban conditions. In youth, the bark is a smooth gray with numerous lenticels. As the tree matures, the bark becomes scaly and peels off, exposing oranges and reds.
	14) Hican—Carya illinoensis X Carya laciniosa This tree is a hybrid of pecan and shellbark hickory. It was developed to produce a nut with the taste of pecan, but with the weaker shell of shellbark hickory.
	15) Pin Oak—Quercus palustris Pin oak is native to the Midwest but is commonly planted throughout the U.S. The tree is predominantly used for ornamental purposes. It is best known for its thick, interlacing branches.
	16) Columnar European Hornbeam— Carpinus betulus “Columnaris” This is a narrow, oval-shaped tree with dense branching. It grows up to 30 feet tall and 15 feet wide. Columnar European hornbeam can be useful as a screen, a hedge, in groupings, and around large buildings.
	17) Sargent Cherry—Prunus sargentii This is one of the first trees to bloom in our area. The deep pink flowers open in late April. The leaves are a shiny dark green in the summer, turning to bronze or red in the fall. The glossy, reddish-brown bark is also attractive.
	18) Katsura Tree—Cercidiphyllum japonicum The Katsura tree has a leaf that is similar in shape to that of the eastern redbud, except for the rounded teeth found in this species. This tree will grow to be 40 to 60 feet tall with an oval shape.
	19) Horse Chestnut—Aesculus hippocastanum Horse chestnut is related to the buckeye tree and grows extensively in the eastern U.S. Like the fruit of the buckeye, that of the horse chestnut is poisonous. Over the years, many students have enjoyed sitting under the expansive branches of this particular tree.
	20) Paperbark Maple—Acer griseum As the name suggests, this tree’s most outstanding feature is its bark. Much like a birch’s, the bark of this tree peels back in paper-thin sheets to show a beautiful cinnamon color. This maple is an import from China and, like most maples from Asia, remains relatively small, growing to 25 feet in height.
	21) European Beech—Fagus sylvatica This species is similar to the American beech but has a darker gray bark. It grows up to 60 feet tall and 45 feet wide. This particular tree is the largest European beech on campus.
	22) Sawtooth Oak—Quercus acutissima This oak grows best in southern climates. The chestnut-like leaves are a dark, lustrous green.
	23) Black Locust—Robinia pseudoacacia Black locust grows faster than many of its eastern forest companions. Its timber is used for making fence posts and railroad ties. It resprouts from stumps so readily that it can take over fence rows, fields, and clearings.
	24) Peirce Pines These various pines were planted in 1874 by 25) Basswood (Redmond Linden)— Tilia americana Basswood, often referred to as linden or linn, has many useful qualities. Flowers from the basswood tree provide a rich commercial honey. The ropiness and flexibility of the wood has proven to be valuable for use in livestock fencing gates. Native Americans made rope from the inner bark.
	25) Basswood (Redmond Linden)— Tilia americana Basswood, often referred to as linden or linn, has many useful qualities. Flowers from the basswood tree provide a rich commercial honey. The ropiness and flexibility of the wood has proven to be valuable for use in livestock fencing gates. Native Americans made rope from the inner bark.
	26) Red Oak—Quercus rubra Red oak is the most commercially important oak. It is a desired timber and ornamental species and can be easily transplanted. Fine furniture and veneer are manufactured from red oak. It is the New Jersey state tree.
	27) Red Pine—Pinus resinosa Red pine is extremely cold-hardy, being able to withstand temperatures of up to 60 degrees below zero. The needles grow in pairs and are four to six inches long.
	28) Bur Oak—Quercus macrocarpa Bur oak is native to the central U.S. It is a slow-growing, stout tree typical of the oak family. It produces an acorn with conspicuous fringes around the cap.
	29) White Ash—Fraxinus americana Its straight, clean form and springy wood have made this tree a favorite since the time of the pioneers. Uses for the wood include skis, tool handles, baseball bats, and crutches. Ash also provides excellent fuel wood and is an effective shade tree.