Fraxinus latifolia aka Oregon Ash

Fraxinus latifolia, or Oregon ash, belongs to the olive family. This tree sheds its leaves each fall. Its native range runs from Vancouver Island south to California. It grows beside streams and across damp lowlands. Garden trees reach 40–80 feet [12–24.4 metres] tall. A straight trunk supports a dense, narrow crown. Trees with room to spread form broad, rounded crowns. Young trees grow fast, then slow as they age. Some live for as long as 250 years.

Dark gray-brown bark forms deep grooves and raised ridges with age. Stout twigs grow in opposite pairs and bear woolly hairs. Young twigs lose their hairs as they age. The leaves also grow in opposite pairs. Each pinnate leaf has five to seven broad leaflets. Their tips taper to points above rounded bases. The edges may be smooth or have small teeth. The end leaflet tends to be wider than the others. Green summer leaves turn yellow or brown in fall.

Small flower clusters open in spring before the leaves emerge. The flowers lack petals and draw little notice. Male and female flowers grow on separate trees. Both sexes must be present for seed production. Female trees bear hanging clusters of winged fruits called samaras. Each fruit holds one seed and measures about one to two inches. The fruits turn brown and ripen in fall. Songbirds, squirrels, and waterfowl eat the seeds. Deer and elk browse leaves and new shoots. Some butterfly larvae also feed on this tree.

Grow Oregon ash in sun or part shade. It suits deep, rich loam and clay with ample moisture. It also grows in sandy, rocky, or gravelly streamside soils. It tolerates seasonal floods and standing water during winter. NC State lists USDA zones 6–9 for this species. Cool, humid summers and mild winters suit it well. Oregon State says established trees can go without summer watering. Yet NC State warns that dry sites can stunt growth. Drought can also cause leaf loss and increase disease risk.

Oregon ash provides shade and suits ponds, meadows, and rain gardens. It can help restore wet ground and provide wildlife cover. Its wind resistance also makes it useful in shelterbelts. People use its wood for furniture, building interiors, barrels, and fuel. Indigenous peoples made paddles and digging tools from the wood. Fungi can cause leaf spot, powdery mildew, and heart rot. Emerald ash borer can kill trees by damaging their inner bark. PFAF records no known food uses or hazards. This does not establish that every part is safe to eat. It records past medicinal uses of roots, twigs, and bark.