Groundnuts

The groundnut is known by many names; the earthnut, tekeneipen, Indian potato, potato bean, hopniss, or by many aficionados, simply Apios. A nitrogen-fixing root crop, it has captured the attention of humans for thousands of years. It was one of the earliest native crops to find its way to Europe, documented as early as 1585.¹ Part of Fabaceae, it is included in the pea family, and while the beans themselves are not seen as a primary crop, it is a reminder of the historical ecological role they play in the ecosystem.

Now, unlike many of the species we have covered to date, apios doesn’t appear to have any unique specialist relationships with pollinators; leaf cutter bees and honeybees have been documented extensively on the flowers, and those still seem to have poor reproductive success, suggesting that if they had co-evolved with any specialist pollinator, it no longer exists.²

The flowers of Apios are gorgeous and can be found draped over spicebush in the summer here in New England.

The genus Apios comprises three species native to Asia and two species found in North America. Apios americana is native to Eastern North America from New Brunswick, Canada to Florida and as far west as Texas, thriving in waterlogged soils. Thomas Harriot, who accompanied Sir Walter Raleigh on his expedition in 1584, describes “Openauk”, which are a root “of the bigness of walnuts” that are “fastened with a string” that were boiled for consumption.³ Over a thousand miles north, in New England, John Brereton describes the same, stating that “in every Island, and almost in every part of every Island, are great store of Groundnuts, fortie together on a string, some of them as bigger as hennes eggs.”

Colonel James Smith, under captivity by the Delawares, describes eating the potatoes boiled and dipped in raccoon fat. They were boiled alone, cooked with meat or corn, or roasted directly in hot ashes. The Menominee made preserves by boiling the tubers in maple syrup. The groundnut was primarily a food for the summer, according to early reports, they were often eaten in June, July, and August, alongside berries and fish. However, there are reports of tubers peeled and dried for winter storage— sometimes in maple syrup, and even more described as a winter food in places like modern Virginia. This speaks to the capacity of the groundnut to fill a variety of niches within a community’s diet based on the local ecological conditions, and why the plant was so valued by Indigenous communities.

The plants themselves danced between crop and wild-harvested food. According to William Cronon, groundnuts were harvested wild but also planted along hunting trails and clearings in the forest, providing accessible food regardless of the hunt’s success.⁴ They were considered not a domesticated crop but not quite wild, either. Given their prominence in the diets of so many Indigenous communities, tubers have been dug up on several sites, from Red Cloud Nebraska, near a historical Pawnee village, and from four Ozark sites. On one particular site in Mississippi, groundnuts were found alongside corn, suggesting that the food was still significant even after corn had arrived, which had fundamentally altered the food production of indigenous people across the East Coast.⁵

The landscapes around Indigenous settlements were often managed to support food-producing plants; we’ve covered the extensive selection for hickories, oaks, chinquapins, black walnuts, and butternut, but underneath the canopy in wet regions where the black walnuts called home were pawpaws, groundnuts, spicebush, and more. Colonists described arriving at hunting campsites where Indigenous hunters had dug up massive stretches of groundnuts, a reminder that hunting paths were filled with edible plants similar to the areas around their settlements.

A common trend that we have seen discussing native crops is that apios shows two primary ‘lines’ of genetics; a triploid form that predominated the northern range of the species and a diploid form for much of the south. It is suggested that a combination of the triploid and self-incompatibility is the cause of the sterility of the species over much of the range.⁶ Historically, it was assumed that the driver for the infertile nature of northern species was the season length— however that doesn’t seem to be the case, and it is instead driven by its ploidy status.

As shown in the graph above, Apios in the United States are split into two species; “Medikus” and “Robinson”. Medikus is the groundnut most folks reading this are familiar with, while Robinson is, today, an extremely rare species that offers much less in terms of human consumption.⁷ A. priceana primarily grows in rocky open woodlands, while A. americana thrives in forests, thickets, prairies, riverbanks, and wetlands.

While the groundnut fed the starving pilgrims during their first winter, it has never captured much of the attention of the nation, despite the later successes of blueberries, pecans, and strawberries. However, in 1985, serious research into the viability of Apios as a crop was led by Bill Blackmon & Berthol Reynolds at the Louisiana State University Agricultural Experiment Station in Baton Rouge, Louisiana. The program was short-lived— it continued for 9 years until 1994— despite its successes. Blackmon moved away for personal reasons and later commented that he would not have left if he knew the program wouldn’t continue without him— in his words, “I left LSU. I thought they were going to let Bert continue. Bert, because of his name, continued to work with this plant but they kind of moved him to doing something else else”.⁸ Without their leadership, the LSU project was considered dead.