This unique magnolia relative is easily overlooked during our typical window for highlighting the Garden’s magnificent magnolias – late winter to early spring – as it’s slower to break dormancy. Once winter dormancy has been overcome, however, this species puts on a show all its own.
Instead of an impressive display of white, yellow, pink, or purple flowers, the Chinese tulip tree more modestly delivers a leaf like few others in the plant kingdom. With a silhouette described as the form of a tulip or, if flipped, a t-shirt, this two-lobed, flat-tipped leaf blade is found on only one of two species of plant. Under a light breeze, the lobes on this large leaf blade can catch the current and animate the entire tree. Leaves can be up to 7 by 9 inches or more, and the tree can reach 70 feet tall and 30 to 40 feet wide. Pale, greenish-yellow flowers emerge after the leaves are fully open in late spring and are displayed upright on the stem tips. Though a member of the magnolia family, it is typically the leaf that takes center stage. Fall color is a very attractive yellow.
Found today in central and southern China as well as in far northern Vietnam, this near-threatened species suffers from harvest for timber and from land clearance for agricultural use throughout its range. Remaining populations are small, each with typically fewer than 50 individuals sufficiently mature to flower. As a general rule, small reproductive populations can have challenges setting viable seed, as flowers are few and the likelihood of pollen transfer from flower to flower decreases.
Interestingly, this species has only one close relative – the American tulip tree, also called the tulip poplar. Together, these two species are known as disjunct species, that is, geographically-separated relatives that share a common ancestor. Prior to the breakup of Laurasia, the large, northern half of the supercontinent called Pangaea, tulip trees spanned the contiguous land mass between what was to become China and North America, including Europe. Fossils found today in Europe support this broad, prehistoric distribution. As Laurasia broke up and the Atlantic Ocean formed, the distribution of this ancestor Liriodendron was fragmented and the Eurasian population receded to China as glaciation in Europe created a climate not amenable to their survival. Endemic to eastern North America today, Liriodendron tulipifera can reach 90 feet tall, rarely to 150 feet tall. This species is one of the tallest tree species on the East Coast.
Both species have successfully endeared themselves to us, and as a result are now cultivated widely as ornamentals.
IN BLOOM CONTRIBUTORS: Text by Corey Barnes and Profile by Mona Bourell. Photos by Joanne Taylor, Mona Bourell and David Kruse-Pickler.