The American Bladdernut (Staphylea trifolia) is a unique, small tree, or more often a shrub. This Ohio native, and the Sierra Bladdernut (S. bolanderi) are the only members of the genus Staphylea native to the US. Their distinctive papery fruits and trifoliate compound leaves set them apart.
Bladdernut Leaves
Bladdernut leaves are oppositely-arranged. Opposite leaves (and branches) are attached to the tree directly across from one another, while alternate leaves are not. The main opposite trees in Ohio are the MADBucks: Maple, Ash, Dogwood, Buckeye. Most of the rest, except for a few shrubby trees, are alternately arranged. But Bladdernut is generally more of a shrub than a tree, so it doesn’t fit the MADBuck list of oppositely arranged trees.
The leaves are also palmately-compound, with three finely-toothed, elliptical leaflets per leaf. Palmately-compound leaves have multiple leaves attached at a single point, like the fingers on the palm of one’s hand. Pinnately-compound leaves have leaflets attached at various points on the stem. The leaflets are approximately 1.5 to 3 inches long, and the lateral leaflets have essentially no stem. The leaflets are pinnately-veined. The leaves are deciduous and turn yellow or brown in the fall.
Flowers & Fruits
Bladdernut flowers emerge in spring and consist of small white bells with five petals and yellow interiors. Each flower develops into a papery, three-sided fruit with three points at the bottom. The fruits contain several small seeds similar to popcorn seeds. Bladdernuts are often found near water, and some sources suggest that the bladders evolved to float the seeds downstream for propagation. The fruits are persistent and a few are often present through the winter.
Staphylea trifolia is monoecious and every tree can potentially produce fruits, whereas dioecious trees have male and female flowers on separate trees. Like many or most white or colorful flowers, Bladdernuts are insect-pollinated. Wind-pollinated flowers are more often green. Bladdernuts are self-incompatible, and do not pollinate themselves. They often grow up from runners.
Bladdernuts are usually more shrubby than tree-like, and are usually under 20 feet in height, with multiple trunks. There is no designated Ohio Champion. The trunks are seldom large enough to have obviously characteristic bark.
Identification Summary
ID Summary: Shrub or small tree with three palmately-compound leaves, oppositely-arranged. Three sided-papery fruits in fall that persist into winter.
Similar Trees: The trifoliate compound leaves are similar to those of the Common Hoptree (Ptelea trifoliata), but Hoptree leaves are alternately-arranged, and Hoptree fruits consist of clusters of small round samaras (wafers) with seeds in the middle. Bladdernut fruits are similar to those of the non-native Goldenrain Tree (Koelreuteria paniculata) but Bladdernut fruits have three points at the bottom, and the Goldenrain Tree fruits have one. The large, pinnately-compound leaf of the Goldenrain Tree is easily distinguished from the trifoliate Bladdernut leaf.
American Bladdernuts tolerate a variety of soils, but do best in moist conditions in full sun to partial shade. The trees are short-lived.
Bladdernut Range
Bladdernuts are a small group, with only three species native to the US. One species occurs in the Sierra Mountains, one in southern Florida, and American Bladdernut occurs in the east-central US. Lucy Braun’s The Woody Plants of Ohio indicates that Bladdernuts are found in all of Ohio’s 88 counties, except for seven in the western part of the state. Oddly, several sources indicate that Bladdernuts prefer alkaline soil, despite the fact that western Ohio has predominantly limestone or dolomite bedrock, typically associated with alkaline soil. Bladdernut is not among the top 80 trees in the Columbus, Ohio Street Tree Inventory.
Uses of Bladdernut Wood
There is little or no use for Bladdernut wood.
According to the Native American Ethnobotany Database, Staphylea trifolia was used by American Indians in the following ways:
- Iroquois – Infusion of plants taken for rheumatism,
- Iroquois – Used to treat skin conditions,
- Iroquois – Infusion of powdered bark used as a wash for sore faces,
- Iroquois – Gynecological aid; bark poultice applied “when a woman swells after copulation”,
- Iroquois – Infusion of bark used as a wash to keep children from crying,
- Meskwaki – Seeds used in gourd rattles for ceremonial dances.
Bladdernuts provide human food, but not a lot of it. Each bladder contains several small seeds similar to popcorn seeds that can be eaten raw, when young, or roasted. To me, they taste like pistachios. The seeds were once pressed for edible oil, but gathering them makes one appreciate how much effort was required to survive in earlier times. Several online sources indicated that the flowers of some species of European Bladdernut were pickled for use in Georgian cuisine.
Bladdernut for Wildlife
Several sources indicated that American Bladdernut has relatively little value to animals as well. Howard A. Miller & H. E. Jaques’ How to Know the Trees, claimed that, “It does not appear to have any value for wildlife except possibly as nesting sites for low-nesting species of songbirds”. They did concede that its dense root system is good for soil stabilization. They also mentioned a tree near Utica, Michigan, with a height of 29 feet, a trunk diameter of 4.8 inches, and a crown width of 21 feet (at the time of printing in 1941).
Illinois Wildflowers indicated some faunal associations for American Bladdernut, including:
- The flowers attract various bees, Syrphid flies and dance flies,
- Syrphid flies feed on the pollen and some of the bees collect pollen for their larvae,
- Thrips quinciensis has been observed sucking juices from Bladdernut,
- The Bladdernut Plant Bug (Lopidea staphyleae) feeds on the shrub.
They go on to say that, “Additional information about floral-faunal relationships for this species is scarce. Apparently, White-Tailed Deer are less likely to browse on Bladdernut than other woody shrubs, although the reasons for this preference are unclear.”
This diminutive tree, or mere shrub, apparently has few admirers. But count me in. I always delight in encountering its unique bladders and trifoliate leaves.
You can also listen to my talks on Ohio Broadleaf Tree Identification on YouTube, Part 1 and Part 2.
