Kansas Wildflowers and Grasses

HAIRY ROCKCRESS

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Arabis pycnocarpa M. Hopkins

[=Arabis hirsuta (L. ) Scop.]

Konza Prairie, Riley County, Kansas

Biennial or perennial

Height: 4-32 inches

Family: Brassicaceae - Mustard Family

Flowering Period: May, June, July

Stems:

Erect, simple or branched above.

Leaves:

Basal and cauline, alternate, simple. Basal leaves with petiole .2 to .8 inch; blade spatulate, oblanceolate, or oblong, .4 to 3.2 inches long, .4 to 1 inch wide, margins entire, wavy, or dentate, surfaces sparsely to densely pubescent with simple or branched hairs. Cauline leaves sessile; blade oblong to ovate or lanceolate, .4 to 3 inches long, .12 to 1 inch wide, base nearly cordate to auricled, margins entire to dentate, lower surfaces hirsute or becoming glabrous with age.

Inflorescences:

Racemes, terminal. Fruiting pedicels erect, .08 to .5 inch.

Flowers:

Sepals 4, distinct, oblong, 2.5--4 mm, glabrous; petals 4, white, distinct, .14 to .2 inch, base attenuate; stamens 6, 4 long stamens barely exserted, 2 short stamens included; sigma 1.

Fruits:

Siliques, sessile, strongly ascending or appressed to rachis, linear, 1.4 to 2.6 inches long, .04 to .1 inch wide, slightly flattened; seeds brown, round to oblong, .04 to .07 inch, essentially smooth, winged, sometimes obscurely so.

Habitat:

Bluffs, cliffs, ledges, open floodplains, and rocky sites in tallgrass prairies.

Distribution:

Northeast quarter of Kansas and Cherokee County

Origin:

Native

Comments:

Arabis, Arabia, and pycnocarpa, crowded carpels.

Hairy rockcress leaves