Big Blue Lilyturf, Creeping Liriope (Liriope spp.)

Taxonomy

Domain	Eukarya
Kingdom	Plantae
Phylum	Magnoliophyta
Class	Magnoliopsida
Superorder	Lilianae
Order	Asparagales
Family	Asparagaceae
Subfamily	Nolinoideae
Genus	Liriope

Scientific Name

Liriope muscari

Common Name

monkeygrass

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

The 2 liriope species are similar and even confused in the ornamental trade, with big blue lilyturf being the more common invasive. Both species form dense, evergreen ground cover of crowded tufts of grasslike but thicker leaves, 6 to 18 inches (15 to 45 cm) high and increasing with plant age. Stalked spikelike racemes of small lavender-tolilac flowers jut upward in early summer to yield stalks of small, green-to-black berrylike fruit in summer through winter. Aggressively spreads by radiating underground stems (rhizomes) that produce a spaced sequence of vertical, white plant initiates, being connected in a line for a time. Young plants have a filmy basal sheath around leaves and a swollen taproot that becomes fibrous and intertwining, eventually filling the upper 6 to 12 inches (15 to 30 cm) of soil. Roots produce scattered small, fleshy, peanut-shaped corms that can sprout as well.

Stem

Grasslike tufts of initially interconnected plants lacking a central stem, except for the flower/fruit stalks.

Leaves

Grasslike but fleshier, radiating from the soil surface in expanding tufted groups, 2.5 to 7 inches (6 to 18 cm) long and 0.1 inch (2 mm) wide on new plants, up to 18 inches (45 cm) long and 0.4 inch (1 cm) wide on mature plants, widest at the middle and tapering to a blunt tip. Multiple lengthwise, parallel veins with a distinctly indented midvein and slightly thickened, very finely serrated margins. Glossy green being somewhat lighter beneath with whitish bases. Variegated varieties appear less aggressive. Leaf tips turn brown and die back in winter. New leaves grow from the base in spring.

Flowers

June to August. Multiple slender flower stalks, 15 to 14 inches (6 to 36 cm) tall, with the terminal 1.5 to 4.5 inches (4 to 12 cm) having spaced clusters of tiny lavender or violet (to white) flowers, with yellow centers, opening at different times.

Fruit and seeds

August to February. Spherical, green, berrylike drupes turn blue ripening to black purple, 0.2 to 0.3 inch (6 to 8 mm) wide. Have grapelike skin and little to no pulp, contain a single spherical dark seed.

Ecology

Grow in full sun to shade and a range of soils, spread is most rapid on moist, highly organic soils. Many cultivars are widely planted as ornamental ground cover and can escape to nearby forests by seeds. Displace forest plants to form ground-layer monocultures. Pollinated by insects. Spread by bird- and animal-dispersed seeds and soil movement with rhizomes and corms.

Resembles

Resembles mondo grass (Ophiopogon spp.), a much smaller-leaved common ornamental. Can resemble tall nut-rush (Scleria triglomerata Michx.), a forest nut sedge that has similar clumps of leaves from the soil that are 16 to 24 inches (40 to 60 cm) long, angular flower/seed stalks tipped by brownish leafy bracts that yield tiny, smooth nutlets, white to gray.

History and use

Native to China and Japan. Two of the most common ornamentals planted for ground cover, with both having several varieties.

Distribution

Found in LA, MS, AL, FL, GA, SC, and VA in scattered infestations.

Management strategies

• Remove prior plantings, and control sprouts and seedlings. Bag and dispose of plants, underground corms, and fruit in a dumpster or burn.
• Treat when new plants are young to prevent seed formation.
• Pull, cut, and treat when fruit are not present.
• Frequent repeated mowing can assist control.

Recommended control procedures

• Thoroughly wet leaves with one of the following herbicides in water with a surfactant (June to October with multiple applications to regrowth): a glyphosate herbicide as a 2-percent solution (8 ounces per 3-gallon mix), mix) or, when safety to surrounding plants is not a concern, Arsenal AC* as a 0.5 percent solution (2 ounces per 3-gallon mix), Arsenal PowerLine* as a 1-percent solution (4 ounces per 3-gallon mix), or Journey* as a 3-percent solution (12 ounces per 3-gallon mix) applied to actively growing shoots.

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

Images

August	August	July	December
July	November	September

Download the publication