The American tulip poplar, scientific name Liriodendron tulipifera, is a native tree to North America, ranging from Florida to New England and as far west as eastern Texas. The tree is named for the large orange and yellow flowers it produces that are similar in form to tulip flowers. According to the Native Tree Society, certain tulip poplars number among the tallest and oldest trees in the eastern United States.
The tulip poplar typically grows from a single leader trunk that is usually tall and columnar in form. On mature specimens the lower portion of the trunk is often devoid of any branches. The tree grows relatively fast, with a somewhat oval shape to its canopy that often becomes more irregular as it grows. The canopy typically has an average spread of 40 to 50 feet.
The average height of a tulip poplar at maturity is from 20 to 30 feet. Most trees typically continue growing to a height of from 60 to 90 feet, depending on soil, water and light conditions. The trunk diameter of the typical tulip poplar averages from 4 to 6 feet across with a circumference of between 12 and 18 feet.
The tallest known specimen of tulip poplar currently stands in the Baxter Creek area of the Great Smoky Mountains National Park in North Carolina and is 177.4 feet tall and 11 feet in circumference. Another famous specimen, the Sag Branch Giant, is the second tallest, with an estimated height of 167.7 feet. Other tall specimens of note are also in the park and include the Mill Creek Monster at 156 feet, and the Greenbrier Giant at 146 feet.
When its impressive height is combined with its massive girth of 22 feet, 5 inches, the Sag Branch Giant is considered the largest tulip poplar alive. Other tulip poplars not quite so tall have even larger girths. The Greenbrier Giant is an example, with a girth of 24 feet 3 inches. Tulip poplars also live to be very old, with many trees well over one hundred years of age. The oldest know specimen of Liriodendron tulipifera, according to the Eastern Oldlist database at Eastern Kentucky University, is in the Forge Creek region of the Great Smoky Mountains National Park with an estimated age of over 500 years.