Shrubby Nonnative Lespedezas (Lespedeza spp.)

Taxonomy

Domain	Eukarya
Kingdom	Plantae
Phylum	Magnoliophyta
Class	Magnoliopsida
Superorder	Rosanae
Order	Fabales
Family	Fabaceae
Subfamily	Faboideae
Tribe	Desmodieae
Genus	Lespedeza

Scientific Name

Lespedeza bicolor

Common Name

shrubby lespedeza

Miller, J.H., E.B, Chambliss, N.J. Loewenstein. 2010. A Field Guide for the Identification of Invasive Plants in Southern Forests. General Technical Report SRS-119. Asheville, NC. United States Department of Agriculture, Forest Service. 126 p.

Plant

Perennial, erect, and much branched or ascending leguminous shrubs, 3 to 10 feet (1 to 3 m) in height. Stems clustered at the base with Thunberg’s and single with bicolor. Trifoliate (3-leaflet) leaves, many small purple-to-white pea flowers, and singleseeded pods, from a woody root crown. Dormant brown plants remain upright most of the winter and may sprout at branches in the spring. Species probably hybridize to blur traits.

Stem

Arching branched, upright-to-ascending stems, 0.2 to 0.8 inch (0.5 to 2 cm) in diameter. Thunberg’s often purple when young and bicolor often light tan to gray green. Appressed hairy to hairless.

Leaves

Alternate, 3-leaflet leaves. Thunberg’s leaflets mostly narrowly elliptic to oblong, 0.8 to 2 inches (2 to 5 cm) long, and shrubby broadly elliptic to oval, 0.8 to 1.2 inches (2 to 3 cm) long, both with a hairlike tip. Lower surfaces lighter green than upper surfaces. Petioles 0.8 to 1.6 inches (2 to 4 cm) long. Stipules narrowly linear, 0.04 to 0.3 inch (1 to 8 mm) long.

Flowers

June to September. Clusters (racemes) 4 to 6 inches (10 to 15 cm) long growing from upper leaf axils—each cluster subtended by a tiny ovate bract—composed of 2 to 15 well-spaced, pealike flowers, more drooping in Thunberg’s while shrubby are erect and extending beyond leaves. Each flower 0.3 to 0.6 inch (8 to 15 mm) long and beyond the upper leaves. Petals usually rosy purple in center and often grading to lighter shades, but can vary to white (many cultivars). Sepal teeth sharp with the lowest longer than the tube for Thunberg’s while rounded and shorter than the tube for shrubby.

Fruit and seeds

August to March. Flat legume pod 0.2 to 0.3 inch (6 to 8 mm) long, broadly elliptic with pointed hairlike tip. Green becoming gray and densely appressed hairy, not splitting. Single seed 0.12 to 0.16 inch (3 to 4 mm) long, black for Thunberg’s and mottled purple on green for shrubby.

Ecology

Planted widely in forest openings for wildlife food plots and soil stabilization to later encroach into adjoining stands. Reproduce and spread by abundant seed production even under a medium-to-dense overstory to exclude all other vegetation. Spread encouraged by burning that clears adjoining areas for seeding. Infestations seasonally changes from fire resistant in summer to hot burning in winter. Leguminous nitrogen fixers. Dense infestations hinder or stop recreational access, even by hunters.

History and use

Introduced from East Asia as ornamentals in the late 1800s. Later programs promoted uses for wildlife food and soil stabilization and improvement. Still sold even by States and planted for quail and whitetail deer food plots, while other birds and rodents do not eat the seed.

Distribution

Found throughout the region with scattered dense infestations in every State.

Management strategies

• Treat, cut, or mulch when new plants are young to prevent seed formation.
• Manual pulling and weed wrenching is limited to new seedlings when soil is moist to ensure removal of all roots.
• Minimize disturbance within miles of where these plants occur, and anticipate wider occupation if plants are present before disturbance.
• Burning treatments have limited application in most situations and can worsen infestations.
• While grazing by cattle, sheep, and goats can reduce growth, forage quality varies, and grazing also can spread seeds.

Recommended control procedures

• Thoroughly wet all leaves with one of the following herbicides in water with a surfactant (July to September): Milestone VM* as a 0.1-percent solution (0.5 ounce per 3-gallon mix) applied as 50 gallons per acre, Garlon 4 as a 2-percent solution (8 ounces per 3-gallon mix), Escort XP* at 1 ounce per acre (0.2 dry ounce per 3-gallon mix), a glyphosate herbicide as a 2-percent solution (8 ounces per 3-gallon mix), or Velpar L* as a 2-percent solution (8 ounces per 3-gallon mix).
• Mowing or mulching 1 to 3 months before herbicide applications can assist control.

* Nontarget plants may be killed or injured by root uptake.

Images

Shrubby: July	Thunberg's: June	Shrubby: July
Thunberg's: June	Thunberg's: June	Shrubby: January	Shrubby: January

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