Stems ascending but decumbent, simple or branched, 5–25 cm high. Leaves 10–25 mm long, lanceolate with rounded tips. Flowers: sepals attenuate-lanceolate, 4–7 mm long; petals as long as sepals. Capsule 4–6 mm long with yellow seeds
(Lesica 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX).
Montana has 3 native and 1 exotic species of
Hypericum. All have leaves that are opposite, sessile, entire, and dotted with translucent glands. Hold a leaf up to the sunlight and see the glands.
Larger Canadian St. John’s-wort -
Hypericum majus, native and desirable
* Mature plants are 5-25 cm tall, grow decumbant.
* Smaller flowers with 5-yellow petals not outlined by black glands and about as long as sepals.
* Habitat along rivers, ponds, and lakes in valley and montane zones.
Western St. John’s-wort –
Hypericum scouleri, native and desirable
* Mature plants are 5-60 cm tall.
* Large flowers with 5-yellow petals outlined by black glands.
* Sepals are ovate with rounded tips and amber veins.
* Rhizomatous and stoloniferous.
* Habitat is moist to wet areas in meadows, along streambanks, and on ledges from the valleys to the alpine zones.
Common St. John’s-wort -
Hypericum perforatum, exotic and noxious
* Size: Mature plants are 25-75 cm tall.
* Flowers: 5-yellow petals outlined by black glands and showy yellow stamens.
* Sepal: 5 linear-lanceolate with acute tips.
* Branches: reddish-colored that help make the plant more noticeable in fall.
* Fruit: a 3-valved capsules with many, tiny seeds.
* Roots: taprooted and rhizomatous.
Tinker’s-penny -
Hypericum anagalloides, native and desirable
* Mature plants are 2-12 cm tall, grow along the ground, and root at leaf nodes.
* Smaller flowers with 5-yellow petals not outlined by black glands and slightly longer than sepals.
* Habitat of wetlands and wet soil in meadows along streams in montane and subalpine zones.
