Article by Frank Dennis Bishop, Jr.
FAMILY: Betulaceae
DESCRIPTION: The 1890 edition of the North American Botany described Carpinus as the following: "Staminate flowers--aments cylindric: scales ovate, acute, ciliate near the base: anthers slightly bearded at the summit. Pistillate flowers--aments oblong, loosely imbricated, bracteate, with the flowers in pairs: scales unequally 3-lobed, 1-flowered, persistent, enlarging and becoming foliaceous: perianth urceolate, 6 toothed, incorporated with the ovary: styles 2, united at the base: not bony, ovate, acute, sub-compressed, ribbed." (Eaton and Wright, 1890). Today the hornbeams are described as deciduous, hardwooded trees and rarely described as shrubs with smooth or scaly bark. The hornbeams are associated with hop-hornbeams, hazels, and birches. The trees have zigzag twigs and alternate, toothed leaves. The leaves are more or less in two ranks and have unbranched, parallel veins running outward from the midribs. The flowers of the hornbeams are unisexual with the sexes in separate catkins on the same plant (Everett, 1981). The tree has slender shoots and slender conic to oviod buds with the terminal bud absent. The hornbeam has male catkins opening from buds in spring which are not exposed in winter and flowers solitary below small bracts. The flowers have six to twenty stamens and the flower is wind pollinated. Each flower is set on a large trilobed to simple serrate floral bract. The hornbeam has fruit that is a ribbed nut subtended by a floral bract (Huxley, 1992).
IDENTIFICATION KEY:
Trees of the Northern United States and Canada
The New Royal Horticulture Society Dictionary of Gardening
GENERAL INFORMATION: Carpinus is confined to the Northern Hemisphere, and is distributed from the Province of Quebec through the eastern United States to the highlands of Central America, Sweden to Southern Europe, Asia Minor, temperate Himalayas, Korea, southern China, and Japan (Sargent, 1933). Carpinus is made up of some thirty-five species and flourishes on most soils (Everett, 1981). The hornbeam grows very slowly and is raised from seed which is slow to germinate. The tree has ornamental value and its rounded heads of foliage are rarely subject to insect attacks and have attractive autumn tints (Seymour, 1990). In spring, the hornbeam bears attractive yellow catkins, through to their autumn display of long pendulous clusters of fruit with autumn colors of clear yellow, old gold, and crimson (Huxley, 1992). The wood of the hornbeam is extremely hard and difficult to work with. In the past, the wood had been used as wheel spokes and axils, and charcoal for gunpowder. The wood is also an excellent fuel (Everett, 1981).
REFERENCES:
Eaton, Amos & John Wright. 1890. North American Botany. Elias Gates. Troy, NY. pg.
90.
Everett, Thomas. H. 1981. The New York Botanical Garden Illustrated Encyclopedia of
Horticulture. Garland Publishing Inc. New York, NY. pg. 626-7.
Farrar, John L. 1995. Trees of the Northern United States and Canada. Iowa State
University Press. Ames, Iowa. pg.306.
Furlow, J. J. 1987. The Carpinus Caroliniana Complex in North America. Lawrence,
Kansas. pg. 416, 428-9.
Hooker & Jackson. 1895. Index Kewensis. "Carpinus, Linn. Gen. ed. I. 292 (1737)
CUPULIFERAE, Benth. & Hok. f. iii. 405". At the Clarendon Press. Oxford.
(Could have been used for oringinal citiation and general info but was not available).
Hurley, Anthony & Mark Griffiths ed. 1992. The New Royal Horticultural Society
Dictionary of Gardening. Macmillan Press Limited. London. pg. 523-4.
Sargent, Charles. 1933. Manual of the Tress of North America. Riverside Press. Boston,
MA. pg. 201.
Seymour, E. L. D ed. 1990. The Wise Garden Encyclopedia. Harper Collins. New York,
NY pg. 200-1.
Stapf, O. 1930. Index Londinensis. "Gard & Forest, vi. 365 (1893)". At the Clarendon
Press. Oxford. (Could have been used but was not available).