Description
Yerba Buena is an aromatic perennial herb borne from a woody rootstock with short ascending branches and creeping above-ground stems which often root. The stems and branches are square in cross-section. The leaves are opposite, have short petioles (stalks), are 1-3.5 cm long and oval to almost round in shape, and have bluntly toothed margins and sunken, resin filled dots on the surfaces. Flowers are borne singly on 5-15 mm long pedicels (stalks) in the leaf axils. The calyx is 4-5 mm long and tubular shaped with 12-15 nerves and 5 teeth. The corolla is tubular with distinct short upper and lower lips at its mouth; it is 7-10 mm long, white to cream or purple-tinged, slightly hairy on the outside, and bears 4 stamens on the inside. There is a single pistil with a long slender style (stalk) that has a 2-branched tip.
Diagnostic Characteristics
The only species of its genus in Montana. Distinguished from other mints by combining creeping stems, bluntly toothed leaf margins, and solitary, axillary, pedicellate flowers, each with a 5-toothed calyx, 2-lipped corolla, and 4 stamens.
Habitat
Open woods and dry slopes.