College Park Wild: Down yonder in the pawpaw patch

By Rick Borchelt

Welcome to “ha’siminikiisfwa,” or pawpaw moon in the Shawnee tongue — the month we know as September. Along the region’s woodland rivers and streams, and in our sheltered coves and valleys, pawpaw trees are dropping fat, fragrant fruit during this brief autumn window. The pawpaw’s a strange tree with strange tropical fruit, and we’re lucky to have them here.

Strange, because no other tree in the Mid-Atlantic has the pawpaw’s combination of huge leaves — a foot-and-a-half or more long and half as wide — on a small, 20-foot-tall trunk that bears large, fleshy fruit: indeed, the largest of any native fruit north of Mexico. The pawpaw is the only temperate-climate representative of Annonaceae, a large family of tropical trees. Their fruit are commonly called custard-apples for their sweet, yellow flesh.  

Pawpaws are known to science as Asimina triloba, the genus name Asimina being an adaptation of several similar Native American names for pawpaw, through the colonial French to the standard scientific Latin. The common name pawpaw is likely a corruption of papaya; European colonists may have been misled or confused by the two species’ similar fruits. Pawpaws have an abundance of other regional common names, too — wild banana, prairie banana, Hoosier banana, Ozark banana and banango among them. 

Despite its tropical origins, pawpaw currently grows wild in 26 eastern and midwestern states.  One reason for the pawpaw’s widespread distribution here, outside the tropics, may be that the species was deliberately cultivated and traded by Indigenous peoples well north of Maryland, up into the New York area, long before European settlers arrived on the continent. 

The pawpaw’s ecological backstory predates European exploration by hundreds of thousands of years. Its large fruit and huge black seeds suggest it evolved with the giant megafauna of the Pleistocene epoch — ground sloths, tapirs, and giant, armadillo-like glyptodonts among them.  These large animals would have been able to eat the six-inch fruit whole and swallow the large seeds, which the roaming animals would later deposit in their dung perhaps miles from where they ate their meal. These large mammals were wiped out in North America about 12,000 years ago; since then, pawpaws have been spread naturally by less-efficient herbivores like black bears and raccoons — and by Indigenous peoples deliberately cultivating them.  

Left to their own devices, though, pawpaws don’t rely exclusively on spreading seeds to expand their territory. These trees often mass in large orchards along streams and riverbanks as a parent tree sends up new shoots from its spreading roots. These large pawpaw patches are actually a single tree, with all the clones still connected by a root system to the parent pawpaw.  

You can also collect seeds from ripe fruit and grow pawpaws yourself. I now have a sizable orchard of a half-dozen trees in my backyard from a single seed I planted a decade ago.  

If the pawpaw’s slightly smelly, maroon flowers are successfully pollinated in spring, the tree will grow fruit over the summer that looks like a fat, green oblong banana. Unlike most fruit, pawpaws stay green until they’re ripe, which allows the fruit to contribute energy to the tree through photosynthesis as it ripens. The skin develops dark brown or black blotches that signal it’s ripe and ready to eat. Fully ripe fruit falls to the ground, which is where most of its Pleistocene diners would have eaten it.  

That the Shawnee and many other tribes had their own words to honor the pawpaw hints at its long history with Indigenous peoples of the Americas.  Pawpaw seeds and fibers have been found at Native American sites dating back millennia. The first post-colonization reference to pawpaws is attributed to Spanish explorer Hernando de Soto, who in 1541 described Mississippian Indian cultures growing and eating the fruit.

Modern pawpaws also have their share of devotees. While most pawpaw aficionados prefer to eat the fruit fresh, some split them and use the fragrant flesh for baking bread, or in puddings and custards. The taste of the fruit varies considerably among different populations of pawpaws;  people describe the taste as being similar to mangos, bananas or papayas.  

Mammals aren’t the only fans of pawpaws, though; the leaves are the sole food source for the caterpillars of one of Maryland’s iconic butterflies, the zebra swallowtail (Eurytides marcellus). If you see a zebra swallowtail on the wing, you can bet you’re in the presence of a significant pawpaw patch!

Over the next few weeks, you can find your own pawpaws in nearby woodlands along Northeast Branch, Paint Branch and Indian Creek; at Lake Artemesia; along the Anacostia; and along the Patuxent River in places like the Patuxent Wildlife Research Refuge, near Laurel, and Governor Bridge Natural Area in Bowie. Pick from the fruits that have already fallen but are not yet decaying; these will be ripe, while the green fruit still on the tree is almost always too astringent to eat. 

But you’ll have to beat the foxes and their friends to the feast, and you can’t wait too long — pawpaw season is short! 

###

Have questions for Rick about the world of nature in and around the city, or suggestions for future College Park Wild columns? Drop him a note at rborchelt@gmail.com.