Yellow poplars (Liriodendron tulipifera), also called tulip trees are tall straight fast-growing trees with great fall color. Trees often attain heights of a hundred feet or more. They also require little or no pruning to develop a uniform and dense canopy. These attributes make them a good choice for landscape shade trees.
Another plus is that yellow poplars are also native trees. An increasing number of folks are concerned about the invasive effects of exotic species.
They grow well in moist soils but sometimes struggle on dry sites. Trees also don’t tolerate pollution or salt spray very well. They also can be susceptible to aphids and tulip tree scale as well as verticillium wilt if drought-stressed.
Yellow poplars also have relatively soft wood and loads of foliage and fruit residue to deal with. That’s not so good, but I don’t think it’s bad enough to reject using them.
Along property lines they are awesome. Yellow poplar also can be well suited to large lawns since they grow tall enough to be planted well away from structures and still provide shade to the yard.
The foliage of these giants is intriguing. Leaves are large and shaped somewhat like the face of a cat. The upper two lobes are pointed and look like the ears. The sides stick out like a cat’s cheeks. In the fall, these leaves turn a bright yellow. The bark is an attractive light gray color. Flowers resemble tulip flowers.
From a forestry standpoint, they are a very valuable tree, but they aren’t really a true poplar. They are in the magnolia family. Their wood does resemble the true poplars, which we commonly call aspens. Their wood is soft, but it is straight-grained, lightweight and easy to work.
These magnolia relatives also self-prune effectively. This means they naturally shed their lower branches, so lumber has few knots. Copious quantities of clear boards can be sawed from each tree. We use the wood for construction lumber and fencing, and because of the straight uniform grain, they take stain and paint evenly.
In nature, yellow poplars often form pure stands. This is because they are what we call intolerant trees. Seedlings must have full sunlight to develop, so they establish in abandoned sites or after clear-cut timbering operations, assuming mature trees are nearby.
Historically, herbalists have used these trees to treat a variety of ailments. The bark contains an alkaloid called tulipferine. Native Americans once chewed it as an aphrodisiac. This sounds interesting; however, I have no personal experience with it.
Inner bark from yellow poplar species here and in China are steeped into teas to treat fever and digestive problems. Many early settlers used the bark this way. The tea is a natural diuretic, so people also used it as a quinine substitute. These preparations are rarely used now, but there have never been any reported ill-effects from them.
It’s amusing. Yellow poplar is one of our most common and recognized trees but one not often used ornamentally. With the trend toward using native species for landscaping, I bet that might change.
Leaf with catface appearance
Ted Manzer teaches agriculture at Northeastern High School.