Fraxinus

A fast-growing, very adaptable North American ash that was once one of the most planted street and shade trees in the United States and Canada, and that the emerald ash borer is now killing across its range. NC State Extension and the Missouri Botanical Garden both say plainly that planting new green ash trees is no longer recommended. It is native to floodplains, riverbanks and swamps from the Atlantic to the Great Plains, tolerates wet ground, drought, wind, salt and city soil, and has compound leaves, gray-brown diamond-ridged bark and yellow fall colour. Existing trees are worth knowing and, where valued, protecting; for a new tree, choose a different genus.

A large native canopy tree of eastern North America, white ash (Fraxinus americana) is prized for its straight timber, compound leaves, and reliable purple-to-maroon fall color. HONESTY: it can no longer be recommended for new planting across most of its range. The emerald ash borer (EAB, Agrilus planipennis) is a near-certain lethal threat wherever it has spread, killing essentially all untreated ash within a few years of infestation. Treat this record as documentation of a historically important species, not a planting recommendation - plant only where EAB is confirmed absent and you are committed to lifelong systemic treatment, otherwise choose a non-ash canopy alternative.