Hypericum hypericoides ssp. multicaule (Michx. ex Willd.) N. Robson

St. Andrew's Cross


CC = 8
CW = 3
MOC = 47

© DETenaglia

Family - Hypericaceae

Habit - Perennial shrub to 30 cm tall.

Stems - Woody, sprawling to erect, much branched, multiple from base. Bark reddish brown, smooth, peeling in thin strips or flakes. Twigs angled or ridged below each leaf, reddish brown, the older stems usually angled below each leaf, glabrous.

Hypericum_hypericoides_ssp_multicaule_stem.jpg Stem and nodes.

© SRTurner

Leaves - Opposite, simple, decussate, sessile, obscurely jointed just above the base, more or less evergreen. Leaf blades 5-35 mm long, 2-8 mm wide, oblanceolate, rounded to bluntly pointed at the tip, tapered or narrowed at the base (sometimes with a pair of minute, rounded lobes at the jointed base), the margins often slightly rolled under at maturity, herbaceous to somewhat leathery in texture, with 1 main vein visible (sometimes difficult to observe), the surfaces with minute resinous dots, these yellowish brown to dark green or nearly black, the upper surface green, the undersurface slightly paler, not glaucous.

Hypericum_hypericoides_ssp_multicaule_leaves.jpg Stem and leaves.

© SRTurner

Hypericum_hypericoides_ssp_multicaule_leaf2.jpg Leaf abaxial.

© SRTurner

Inflorescences - Usually of solitary flowers at the branch tips and upper leaf axils, occasionally with small clusters of 3 flowers at the branch tips. Pedicels to 3 mm long. Flowers subtended by pair of brown attenuate bracts to 2 mm long.

Hypericum_hypericoides_ssp_multicaule_inflorescence.jpg Inflorescence.

© SRTurner

Hypericum_hypericoides_ssp_multicaule_inflorescence2.jpg Inflorescence.

© SRTurner

Flowers - Zygomorphic. Sepals 2 or 4, usually with minute, yellowish brown to dark green or black resinous dots, the outer pair 5.0-12.5 mm long, becoming somewhat enlarged at fruiting, broadly ovate to narrowly elliptic, rounded to shallowly cordate at the base; the inner pair absent or 1-4 mm long, lanceolate to narrowly lanceolate. Petals 4, grouped into 2 pairs, 6-11 mm long, narrowly oblong-elliptic to narrowly obovate or less commonly obovate, pale yellow to lemon yellow, lying flat on large sepals below, shed before fruiting. Stamens 35-50, the filaments not fused into groups. Ovary superior, flattened-ovoid, 3 mm long, 1.5 mm broad at base, glabrous, from 2 carpels but 1-locular, the placentation parietal. Styles 2, free above the base, somewhat spreading or curved outward, the stigmas minute.

Hypericum_hypericoides_ssp_multicaule_flower.jpg Flower.

© DETenaglia

Hypericum_hypericoides_ssp_multicaule_flower1.jpg Flower.

© SRTurner

Hypericum_hypericoides_ssp_multicaule_flower2.jpg Flower.

© SRTurner

Fruits - Capsules 5-9 mm long, elliptic-ovoid, widest at or slightly below the midpoint, tapered abruptly to the short beaks, flattened and thus narrowly elliptic in cross-section. Seeds numerous, 0.6-0.8 mm long, the surface with fine longitudinal lines, these sometimes forming a faint network, dark brown to purplish brown.

Hypericum_hypericoides_ssp_multicaule_fruits.jpg Fruits.

© SRTurner

Hypericum_hypericoides_ssp_multicaule_fruit1.jpg Fruit (sepals partially removed).

© SRTurner

Hypericum_hypericoides_ssp_multicaule_fruit2.jpg Fruit and seeds.

© SRTurner

Flowering - July - October.

Habitat - Forests, streambanks, pond margins, roadsides, open, disturbed areas, usually on acidic substrates.

Origin - Native to the U.S.

Other info. - This plant is found in the southern half of Missouri. Its range begins in eastern Oklahoma and extends eastward in a broad band through Missouri and continuing nearly to the Atlantic Coast. The plant is easy to identify by its distinctive flowers, which have two opposing pairs of petals arranged in a flattened "X" pattern. The stems are woody, with older ones having reddish shredding bark. Usually only a few (if any) flowers are present, rather than a showy display. The plant is usually found in areas of acidic substrate.

The ssp. multicaule listed here has a low, somewhat decumbent and matted growth form. Some authors elevate this form to species level, as Hypericum stragulum W.P. Adams & N. Robson. The other subspecies found in Missouri is ssp. hypericoides, which has a more erect growth form, reaching 1 m in height, and leaves that are linear to narrowly elliptic. This form is much less common in the state.

Photographs taken in the Ozark Scenic Riverways, Shannon County, MO., 7-1-03 and 7-7-04 (DETenaglia); also at Crowley's Ridge Conservation Area, Stoddard County, MO, 7-17-2009, LaBarque Creek Conservation Area, Jefferson County, MO, 8-22-2010, St. Francois State Park, St. Francois County, MO, 7-9-2020, and Taum Sauk State Park, Iron County, MO, 8-4-2020 (SRTurner).