Draba reptans (Lam.) Fern. - Whitlow Grass
Family - Brassicaceae
Stems - To +10cm tall, erect, from a branched taproot, branching, purplish below, with stipitate stellate pubescence, becoming glabrous near apex of stems.
Close-up of stem with stellate hairs.
Leaves - Alternate, ovate, sessile to short-petiolate, entire, +2cm long, -1mm broad, with stipitate stellate pubescence, mostly basal but with some cauline.
Cauline leaves.
Inflorescence - Terminal compact raceme. elongating in fruit. Pedicels to 5mm long in flower, longer in fruit.
Flowers - Petals 4, clawed, white, glabrous. Claw to .7mm long. Limb to 2.1mm long, 1.8mm broad, rounded at apex. Stamens 6, erect. Filaments to 1.4mm long, white, glabrous. Anthers yellow, .3mm long. Ovary terete, green, 2mm long, glabrous, .7mm in diameter. Style lacking. Stigma small. Sepals 4, erect, oblong-elliptic, 2.1mm long, 1.5mm broad, glabrous, green. Margins slightly scarious. Silicles compressed, to +1.5cm long, 2-3mm broad, linear, glabrous to minutely pubescent.
Calyx close-up.
Flowers close-up.
Fruits close-up.
Flowering - February - May.
Habitat - Rocky open ground, glades, pastures, roadsides, railroads.
Origin - Native to U.S.
Other info. - This tiny species is found scattered throughout Missouri. It is easily overlooked as are many of the plants in this genus.
Steyermark lists two varieties for the plant. Variety reptans has glabrous fruits.
Variety micrantha (Nutt.) Fern. has fruits which are minutely pubescent. The former variety is much more prevalent in Missouri.
Photographs taken at Eagle Bluffs Conservation Area, Boone County, MO., 3-14-03 and 4-11-04.
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