Barbarea vulgaris R. Br. - Yellow Rocket
Family - Brassicacaea
Stems - To -1m tall, multiple from base, branching, glabrous, herbaceous, from taproot, erect, carinate, greenish-purple.
Leaves - Alternate. Lower leaves lyrate, petiolate, glabrous or with some sparse pubescence, to +20cm long. Lobes with coarse shallow teeth or entire. Upper leaves reduced, sessile, entire or with a few coarse teeth.
Inflorescence - Compact terminal racemes elongating in fruit to +40cm long. Flowers on pedicels to 3mm long. Pedicels elongating in fruit to 6mm long, 4-angled, glabrous.
Flowers - Petals 4, yellow, free, 7-8mm long, 2-3mm broad, truncate at apex, glabrous, tapering and lighter yellow to white at base. Stamens 6, erect. Longer 4 stamens with filaments to 4mm long. Filaments glabrous, whitish yellow, with glands at base. Anthers yellow, 1.1-1.5mm broad. Ovary (sub)terete, green, glabrous, 4mm long. Style 1.8mm long, persistent. Stigma sub-biglobose. Sepals 4, greenish-yellow, glabrous, 4-5mm long, 1-1.5mm broad, with lighter yellow margins.
Fruit - Siliques glabrous, many seeded, erect to spreading, 2-3cm long, slightly compressed, beaked. Beak to 3mm long.
Flowering - April - June.
Habitat - Waste ground, disturbed sites, pastures, roadsides, railroads.
Origin - Native to Eurasia.
Other info. - Its hard to
miss this plant in the middle of spring. The bright and abundant yellow
flowers dominate the roadsides and waste places. It is yet another one
of aggressive, introduced members of the Brassicaceae
we see so often in this state. Care should be taken not to spread the plant.
Photographs taken at Danville Conservation Area, Montgomery County, MO., 4-17-04.