Liriodendron tulipifera—known as the tulip tree, American tulip tree, tulipwood, tuliptree, tulip poplar, whitewood, fiddletree, lynn-tree, hickory-poplar, and yellow-poplar—is the North American representative of the two-species genus Liriodendron (the other member is Liriodendron chinense), and the tallest eastern hardwood. It is native to eastern North America from Southern Ontario and possibly southern Quebec to Illinois eastward to southwestern Massachusetts and Rhode Island, and south to central Florida and Louisiana. It can grow to more than 50 m (160 ft) in virgin cove forests of the Appalachian Mountains, often with no limbs until it reaches 25–30 m (80–100 ft) in height, making it a very valuable timber tree. The tallest individual at the present time (2021) is one called the Fork Ridge Tulip Tree at a secret location in the Great Smoky Mountains of North Carolina. Repeated measurements by laser and tape-drop have shown it to be 191 feet 10 inches (58.47 m) in height.[4] This is the tallest known individual tree in eastern North America.
It is fast-growing, without the common problems of weak wood strength and short lifespan often seen in fast-growing species. April marks the start of the flowering period in the Southern United States (except as noted below); trees at the northern limit of cultivation begin to flower in June. The flowers are pale green or yellow (rarely white), with an orange band on the tepals; they yield large quantities of nectar. The tulip tree is the state tree of Indiana, Kentucky, and Tennessee.
Description
The tulip tree is one of the largest of the native trees of eastern North America, known in an extraordinary case to reach the height of 58.5 m (192 ft)[5] with the next-tallest known specimens in the 52–54 m (170–177 ft) range.[6] These heights are comparable to the very tallest known eastern white pines, another species often described as the tallest in eastern North America.
The trunk on large examples is typically 1.2–1.8 m (4–6 ft) in diameter, though it can grow much broader. Its ordinary height is 24–46 m (80–150 ft) and it tends to have a pyramidal crown.[7] It prefers deep, rich, and rather moist soil; it is common throughout the Southern United States. Growth is fairly rapid.[8]
The bark is brown, furrowed, aromatic and bitter. The branchlets are smooth, and lustrous, initially reddish, maturing to dark gray, and finally brown. The wood is light yellow to brown, and the sapwood creamy white; light, soft, brittle, close, straight-grained. Specific gravity: 0.4230; density: 422 g/dm3 (26.36 lb/cu ft).
Winter buds are dark red, covered with a bloom, obtuse; scales becoming conspicuous stipules for the unfolding leaf, and persistent until the leaf is fully grown. Flower-bud enclosed in a two-valved, caducous bract.
The alternate leaves are simple, pinnately veined, measuring 125–150 mm (5–6 in) long and wide. They have four lobes, and are heart-shaped or truncate or slightly wedge-shaped at base, entire, and the apex cut across at a shallow angle, making the upper part of the leaf look square; midrib and primary veins prominent. They come out of the bud recurved by the bending down of the petiole near the middle bringing the apex of the folded leaf to the base of the bud, light green, when full grown are bright green, smooth and shining above, paler green beneath, with downy veins. In autumn they turn a clear, bright yellow. Petiole long, slender, angled.
- Flowers: May. Perfect, solitary, terminal, greenish yellow, borne on stout peduncles, 40–50 mm (1+1⁄2–2 in) long, cup-shaped, erect, conspicuous. The bud is enclosed in a sheath of two triangular bracts which fall as the blossom opens.
- Calyx: Sepals three, imbricate in bud, reflexed or spreading, somewhat veined, early deciduous.
- Corolla: Cup-shaped, petals six, 50 mm (2 in) long, in two rows, imbricate, hypogynous, greenish yellow, marked toward the base with yellow. Somewhat fleshy in texture.
- Stamens: Indefinite, imbricate in many ranks on the base of the receptacle; filaments thread-like, short; anthers extrorse, long, two-celled, adnate; cells opening longitudinally.
- Pistils: Indefinite, imbricate on the long slender receptacle. Ovary one-celled; style acuminate, flattened; stigma short, one-sided, recurved; ovules two.
- Fruit: Narrow light brown cone, formed from many samaras which are dispersed by wind, leaving the axis persistent all winter. September, October.[9]
Harriet Louise Keeler provided a description of the tulip tree in Our Native Trees and How to Identify Them. [a]