Lespedeza cuneata (Dum. Cours.) G. Don

Sericea Lespedeza


CC = *
CW = 3
MOC = 78

© SRTurner

Family - Fabaceae/Faboideae

Habit - Perennial forb.

Stems - Ascending to erect, to 1.5 m, often multiple from a woody caudex, unbranched or branched above the midpoint, densely pubescent with appressed to somewhat spreading hairs mostly confined to conspicuous, white, longitudinal ridges running the length of the stem.

Lespedeza_cuneata_stem.jpg Stem and nodes.

© SRTurner

Leaves - Alternate, trifoliate, petiolate, stipulate. Petioles 2-12 mm long (shorter toward the stem tip), densely pubescent with appressed or slightly spreading hairs. Stipules 2-8 mm long, hairlike. Leaflets 1-3 cm long, 2-6 mm wide (mostly more than 3 times as long as wide), those of the uppermost leaves usually smaller, narrowly oblanceolate to narrowly oblong, narrowly angled or tapered at the base, truncate at the tip, but sometimes shallowly notched and usually with an abrupt, minute, sharp point at the very tip, often with a grayish appearance, both surfaces densely appressed-hairy or the upper surface sometimes becoming glabrous. Axillary clusters of leaves sometimes present.

Lespedeza_cuneata_leaf1.jpg Leaf adaxial. Leaflet shape is usually wedgelike, with the widest part toward the tip.

© SRTurner

Lespedeza_cuneata_leaf2.jpg Leaf abaxial.

© SRTurner

Lespedeza_cuneata_leaf1a.jpg Leaf adaxial, showing the herringbone venation which differentiates this plant from native species of Lespedeza.

© SRTurner

Lespedeza_cuneata_leaf2a.jpg Leaf abaxial surface.

© SRTurner

Lespedeza_cuneata_leaf.jpg Pressed leaf.

© DETenaglia

Inflorescences - Axillary clusters of 1-4 flowers from the median and upper leaves, shorter than or nearly equal to the associated leaves.

Lespedeza_cuneata_inflorescence.jpg Inflorescence.

© SRTurner

Flowers - Calyces with the tube 1.0-1.5 mm long, the lobes 2.5-4.0 mm long. Corollas papilionaceous, 5-9 mm long, creamy white with purple markings on the banner, the keel about as long as the wings.

Lespedeza_cuneata_flowers.jpg Flowers.

© SRTurner

Lespedeza_cuneata_calyx.jpg Calyx.

© SRTurner

Fruits - Fruits from open flowers 3.0-4.5 mm long, the calyx nearly equal in length; fruits from cleistogamous flowers 2.0-3.5 mm long, the calyx slightly shorter than to somewhat longer than the fruit. Seeds 1.5-2.0 mm long, olive green to brown.

Lespedeza_cuneata_fruits.jpg Fruit clusters.

© SRTurner

Flowering - August - October.

Habitat - Prairies, glades, streambanks, pond margins, fields, quarries, railroads, roadsides, any open disturbed area. Deliberately seeded in the past.

Origin - Native to Asia.

Lookalikes - L. virginica.

Other info. - This aggressive weed is reviled by land managers and concerned property owners across Missouri and the southeastern quadrant of the continental U.S. It thrives in disturbed areas, invades natural communities, and is difficult to eradicate. Even small scale control efforts are hampered by strong rhizomes which make it very difficult to uproot. It spreads rampantly along roadsides and is readily spread by mowing and grading equipment. The decision to deliberately introduce this species for forage, erosion control, soil enrichment, and as a wildlife food source turned out to be spectacularly ill advised.

Sericea lespedeza is generally easy to recognize, as much as anything by the thick populations which result from its invasion. Identification of nonflowering plants can be a little tricky, as the plant can sometimes resemble the desirable native L. virginica. Close examination of the leaflets will show that they are often wedge-shaped (cuneate), tapered at the base, wider above the middle, and truncate at the tip. In contrast, the native L. virginica has leaflets which are narrowly oblong or elliptic, and rounded at the tip. The noxious weed also has leaflets with herringbone venation, with the lateral veins running straight to the leaflet margins. The native species, in contrast, have looping venation in their leaflets.

The species epithet cuneata means "wedge-shaped," in reference to the leaflets. The common term "sericea," meaning "silky," refers to the silky hairs on the leaves.

Photographs taken in Brown Summit, NC., 9-18-02 (DETenaglia); also at Tyson County Park, St. Louis County, MO, 9-8-2021, along the Al Foster Trail near Glencoe, St. Louis County, MO, 9-9-2021, and at Don Robinson State Park, Jefferson County, MO, 9-19-2021 (SRTurner).