Angelica arguta is a species of angelica known as Lyall's angelica. This is a taprooted perennial herb growing an erect, hollow stem to heights between one and two meters. It produces large, somewhat triangular leaves made up of many toothed, pointed leaflets each up to 9 centimeters long. The top of the stout stem is occupied by an inflorescence in a compound umbel arrangement, with the webbed rays of the umbel up to 10 centimeters long each. The flowers are generally yellowish.
Irrigation is gradually reduced in September and October. Plants are leached with clear water and fertilized with 10-20-20 liquid NPK fertilizer once before winterization.
Use caution as roots contain coumarins (blood-thinning compounds) and may be toxic if eaten fresh. Seeds in tea or tincture form may treat acid indigestion and nausea. Angelica arguta is a species of angelica known as Lyall's angelica. It is native to western North America, where it grows in coniferous forests from British Columbia to Utah.