Description: calamus oil; "sweet flag oil". acorus calamus root oil is an essential oil obtained from the rhizomes of the calamus, acorus calamus l., araceae. it contains beta-asarone (up to 76%), calamene (about 4%), calamol (about 3%) alpha-asarone (about 1%), camphene (about 1%) and some beta-pinene and asaronaldehyde