Sitka Mountain Ash is found mainly on rich moist soils along the borders of streams, or rocky hillsides, usually in association with conifers.
An infusion of the branches can be given to young children with bed-wetting problems as treatment for weak kidneys in order to stop frequent urination. An infusion of the root and branch bark has been drunk in the treatment of stomach problems and rheumatism it can also be used externally as a bath for treating rheumatism. A concoction of the root and branch bark makes a soothing eyewash. The bark can be chewed as a treatment for colds.
Take caution with the seeds, they contain hydrogen cyanide. This is the ingredient that gives almonds their characteristic flavour. Unless the seed is very bitter it should be perfectly safe in reasonable quantities. In small quantities, hydrogen cyanide has been shown to stimulate respiration and improve digestion, it is also claimed to be of benefit in the treatment of cancer. In excess, however, it can cause respiratory failure and possibly even death.