Black Ash

Fraxinus nigra, black ash, is a slow-growing wetland tree of the northern US and Canadian boreal forest, at home in swamps, bogs, and seasonally flooded bottomland where few other trees can compete. Its wood has a rare, culturally important property: pounding a log along its growth rings separates it cleanly into thin, flexible splints without cutting, a technique Indigenous nations across its range — including the Haudenosaunee, Wabanaki, and Anishinaabe — have used for centuries to weave baskets, a living tradition that continues today and depends entirely on access to healthy black ash.

That tradition, and the species itself, is now in serious jeopardy. The emerald ash borer (Agrilus planipennis) has proven especially devastating to black ash — its already-narrow wetland habitat leaves little room for the species to persist elsewhere as the borer spreads, and black ash is classified as Critically Endangered by the IUCN, with some ecologists warning of functional extirpation across large parts of its range within decades. Regeneration is also complicated by black ash's dependence on the specific hydrology of the wetlands it grows in — it cannot simply be replanted on drier upland sites as a workaround. Anyone planting or maintaining black ash today, especially for basketry use, should coordinate with local tribal natural resources programs and university extension seed-banking or resistance-breeding efforts already underway to conserve the species.