Hackelia virginiana (L.) I. M. Johnst.
Family - Boraginaceae
Stems - To 1.5m tall, single
from base but with many divergent branches,(branches perpendicular to stem
axis, horizontal), scabrous, often with purple-black striations, hirsute
and antrorse strigose above, sometimes retrorse strigose below, erect, herbaceous
but tough and stout.
Leaves - Alternate, petiolate.
Petiole winged. Blade to +/-20cm long, +/-7cm broad, ovate to elliptic-ovate
below, becoming lance-oblong above, scabrous, acute, entire, reduced above.
Inflorescence - At anthesis
flowers in a compact coiled cymes at tip of stems. Inflorescence quickly
elongating and become racemose, to +20cm long. Fruits pendant, subtended
by small bract. Petioles to 2mm in flower, elongating in fruit to +4mm
long, dense pubescent.
Flowers - Corolla tube 1.2mm
long, glabrous, white, 5-lobed. Lobes blunt, rounded, -1mm long, 1mm broad,
glabrous, with conspicuous fornices at corolla throat. Fornices white.
Stamens 5, included, adnate at base of corolla tube, alternating with corolla
lobes. Filaments .1mm long, white, glabrous. Anthers yellowish at first,
reddish with age, .3mm long. Ovary 4-lobed, green, tuberculate, .8mm broad.
Style short, included, .2mm long, glabrous, pale yellow to whitish. Stigma
capitate. Calyx tube to .3mm long, pubescent, 5-lobed. Lobes ovate, 1.2mm
long, acute, antrorse pubescent externally, glabrous internally, erect
in flower, spreading in fruit. Calyx accrescent. Fruit a 4-parted globose
capsule, 5-6mm in diameter, with dense bristles. Bristles glochidiate.
Calyx.
Flower.
Fruit.
Flowering - June - September.
Habitat - Open woods, thickets, waste ground.
Origin - Native to U.S.
Other info. - This is a common
species in Missouri and quite a pain if you happen to walk into a fruiting
bush. The fruits cling to clothing and hair better than probably any other
Missouri species. Viewed under a microscope, the bristles of the fruit
have a ring of retrorse barbs at their apices (glochidiate).
The flowers of the plant are incredibly
minute but are easily recognizable as belonging to the family Boraginaceae
because of their tubular 5-lobed design, and the fornices at the base of
the corolla lobes.
Photographs taken in the Ozark Scenic Riverways, Shannon County, MO., 7-20-04.
|