Mountain Ash
Sorbus aucuparia
Washington State Classification
Monitor List
This plant is on the monitor list - it is not a listed noxious weed in Washington.
Quick Reference
Identification
Growth Habit
This (usually small) tree is popular in garden plantings and was frequently planted on homesteads. It can grow up to 50 feet tall.
Leaves
The leaves are compound, made up of 4 to 9 leaflets. Each leaflet is a narrow egg shape, 0.75-2.25 inches long, and have serrated edges.
Flowers
It can take over 10 years for a tree to start producing flowers and fruit. Each flower is made of 5 white petals, and are less than half an inch wide. They grow in flat topped bunches all over the outside of the tree.
Fruit & Seeds
When ripe, the hard berries start green and ripen to orange or orange-red. Inside, they are 5 segmented, each containing 2 flat seeds
Impact
This plant is on the monitor list - it is not a listed noxious weed in Washington. Please contact Sofia Sherman to report locations or for more information.
Ecology & Spread
Habitat
Escaped from gardens and homesteads, birds spread the seed across a landscape. It can survive in full to partial sun, and from sea level to high elevations.
Spread Mechanisms
Reproduction
Seed, frequently spread by birds
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