Discovering the North American Pawpaw Tree, Asimina triloba, (Sort of)

Fruit of the North American pawpaw tree (Asimina triloba) in the author's pawpaw patch. Copyright 2015, Richard Telford

Fruit of the North American pawpaw tree (Asimina triloba) in the author’s pawpaw patch. Copyright 2015, Richard Telford

By Richard Telford

The powerful forces of forest succession threaten always to engulf the 18th-century stonewalls that surround our 1770 center-chimney farmhouse. During the restoration of the house, we largely gave up trying to stem the encroachment of the surrounding forest. However, several years ago, we began in earnest to work to control that encroachment, in great part due to an alarming increase in the number of Lyme ticks in our yard, which resulted in two of our three children being positively diagnosed with Lyme disease. Reducing moist, shaded areas along the edge of a yard through tree cutting, in conjunction with short-cropping the grass and the removal of leaf litter and other detritus, is a critical component in the war on Lyme ticks (Ixodes scapularis) that has become critical to country living in the northeastern United States. I have previously written about the Lyme disease crisis—a word I don’t use lightly.

This past spring, I began cutting back saplings, creating a ten- to twenty-foot buffer along the outer edges of our stonewalls. At the same time, I began clearing and grass-seeding the inner buffer of the wall that separates our front yard from the road. When I first bought the house in 2003, I had noticed a small stand of trees along that wall that looked to be some kind of tropical ornamental that could survive New England winters. This seemed likely, given the line of Japanese maple trees (Acer palmatum) that lined the eastern edge of the yard. The stand on the south road-edge featured alternate broad leaves as long as sixteen inches stem to tip. They seemed conspicuously out of place amidst the maples, hickories, oaks, birches and elms that, along with eastern white pines and hemlocks, define the surrounding forest. Though I had often intended to identify this tropical oddity, I had not done so by this past spring. In the effort to clear the front wall, I began to cut the stand down, and, at the same time, began limbing an adjacent venerable eastern white pine, also a major shade source.

In the spring of 2014, to celebrate the arrival of our third child, a friend had given us a gift certificate for the annual native plant sale offered by the Eastern Connecticut Conservation District. As we mulled over the catalog choices, a particular fruit tree caught our attention, the North American pawpaw (Asimina triloba), which was purported to produce a fruit similar in appearance to bananas but with a flavor and texture more akin to mango. We were intrigued and initially decided to buy a bucket sapling. We reconsidered, however, for two reasons. First, owing to years of successional encroachment, we lacked a light-sufficient, open space in which to plant it. Second, the catalog noted that pawpaw flowers produce an odor similar to that of rotting meat. With conjured visions of a tree that mimicked, albeit on a smaller scale, the most famous of the “carrion flowers,” Titan arum (Amorphophallus titanum), we were reticent to plant one too close to our house and opted instead for a group of native butterfly attractors.

In both the foreground and the background, young pawpaw saplings rise near the trunk of a mature tree, demonstrating the pawpaw's tendency to reproduce quickly, forming large patches. Copyright 2015, Richard Telford

In both the foreground and the background, young pawpaw (Asimina triloba) saplings rise near the trunk of a mature tree, demonstrating the pawpaw’s tendency to reproduce quickly, forming large patches. Copyright 2015, Richard Telford

Fast forward to the early summer of 2015. Having cut about half the trees of the unidentified exotic stand along our front wall, I began to rake out the carpet of leafy detritus and natural mulch that had built up beneath them over decades, unearthing the fragmentary evidence of former property owners: assorted canning jar fragments and several rusted lids, old nails, an 80s-vintage orange foam Big Mac box, assorted hardware encrusted in rust, and, most interesting of all, a faded but still-legible plastic plant nursery tag that offered the life history of and planting tips for the pawpaw tree. The light went on. Gathering a handful of brown, nickel-sized seeds scattered among the leafy debris—mystery seeds that I had noticed every fall but never investigated—I went in the house and completed a quick Google image search for “pawpaw seeds.” With that first search confirming what I expected to see, I completed subsequent searches: “pawpaw leaf,” “pawpaw flower,” “pawpaw bark,” each subsequent search adding additional confirmation. We were the proud owners of a substantial pawpaw stand, more commonly referred to as a pawpaw patch, half of which I had just cut down.

John James Audubon's rendering of a male and female yellow-billed cuckoo (Coccyzus americanus) in a North American pawpaw tree.

John James Audubon’s rendering of a male and female yellow-billed cuckoo (Coccyzus americanus) in a North American pawpaw tree.

Despite my own ignorance of the pawpaw as a native North American tree, according to an article by José I. Hormaza, published by the Arnold Arboretum at Harvard University, its presence in North America was documented as early as 1541 by a member of the De Soto expedition. Hormaza likewise notes that members of the Lewis and Clark expedition relied almost entirely on wild pawpaw fruit for subsistence over several days in September of 1806. In his book Pawpaw: In Search of America’s Forgotten Fruit, Andrew Moore writes of the cultivation of pawpaw trees by several Native American tribes in the pre-Columbian era, noting that tribe members “carrying seeds in satchels rather than their stomachs” likely replaced the traditional dispersal of pawpaw seeds by then-extinct prehistoric megafauna. John James Audubon, in The Birds of America (1827-1838), features the yellow-billed cuckoo (Coccyzus americanus) in the context of a detailed rendering of an insect-damaged pawpaw tree with a cluster of overripe fruit. Hormaza likewise notes that Thomas Jefferson cultivated pawpaw trees at Monticello and even sent both seeds and plants as official ambassadorial gifts to France in the late 18th century. Still, the pawpaw, as suggested by Andrew Moore’s book title, seems largely to have fallen victim to obscurity in the American public consciousness. So perhaps it should not be surprising that I could step out my front door for thirteen years, look directly at our pawpaw patch, even admire its downward-facing crimson flowers in spring, and remain ignorant of its natural history. Still, I am a bit surprised given my predilection to wanting to be able to identify the species of all kinds that occupy our woods.

A pair of pawpaw fruit deep within the branches of mature tree in the author's patch. Copyright 2015, Richard Telford.

A pair of pawpaw fruit deep within the branches of mature tree in the author’s patch. Copyright 2015, Richard Telford.

This summer, with our pawpaw patch thinned and the pine boughs that once shaded it cut back, the more mature of our trees have produced a respectable fruit crop. As I write this, it is still too early to harvest them, but we are eager to do so in mid to late October. They certainly produced fruit in other years, as evidenced by the seeds we would turn up in our fall raking, yet never once did we notice the fruit that followed the spring flowering. This is certainly due in part to the color of the fruit being, at least in our specimens, nearly identical to their leaf color. Even now, with our new awareness, it takes careful looking to see most of the fruit. Still, our failure to see the fruit of previous summers is also just as certainly a product of the fact that we as human beings, collectively speaking, often simply do not see what we are not looking for. And I am reminded in all of this that our minds can always be more open, our senses keener, our curiosity stronger. Natural history writer Edwin Way Teale, in his 1937 book Grassroot Jungles, notes, “Among the tangled weeds of the roadside or in the grassroot jungles of your own back yard, you encounter strange and incredible forms of life.” He later notes, “The more we know, the more we see; our adventures increase with knowledge.” When we are suddenly struck by our lack of such knowledge, as I was with my “discovery” of our pawpaw patch, we can be critical of our own ignorance, or, instead, we can be grateful for the rich and unquantifiable range of knowledge that is offered to us by the natural world. I choose the latter.

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8 thoughts on “Discovering the North American Pawpaw Tree, Asimina triloba, (Sort of)

  1. I have not noticed the smell at all. In fact, I built a swing set for my kids several years ago and it is located directly in front of the patch. My kids play there constantly, so we are near the patch all the time in good weather, and none of us has ever noticed the smell. If you are considering planting a pawpaw and are concerned about the smell, I would not worry about it. Thanks for reading my piece.

    • I have not seen zebra swallowtails, and some quick research indicates that we do not live within their range, which is south of us. We do see tiger swallowtails and spicebush swallowtails with some regularity, especially the latter, as our woods produce a bumper crop of spicebush (which, as an aside, we boil to make a very fragrant tea).

      • Do you~that is interesting. We get tigers too, and sometimes spicebush but not often. I think it is when their population has done well in a given season and they “spill over” up this way. More common are black swallowtails, their caterpillars on Queen Anne’s Lace and parsley. I am curious to see whether southern species expand north as temps rise.

  2. I think that a lot of species have already shifted their ranges due to anthropogenic climate change and other anthropogenic influences (think of all the human-transported invasive species, for example). It makes sense to me that this would result from a multiplicity of factors, e.g. if a plant shifts its range northward due to climate change, then the species it attracts and hosts may likewise shift if conditions are sufficiently favorable, and if other species requiring the same resources cannot outcompete the new arrival. This has, no doubt, gone on for millennia. The larger issue, of course, is that we are triggering rapid changes through human action that might previously have taken thousands of years. Species went extinct long before humans had the power to make them do so, but now we have the capacity to drive those extinctions at an exponential rate.

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