Invasives_Content Page_Wavy leaf basket grass

Wavy leaf basket grass

(Oplismenus hirtellus ssp. undulatifolius)

Photo of wavy leaf basket grass
Photo credit: Kerrie L Kyde

An aggressive, stoloniferous perennial grass with wavy leaf blades. Grows in deep shade, invading undisturbed forest habitats.

Overview map of prohibited classification in WI
Prohibited (red) counties

Other names for this plant include:

  • Common names: basketgrass, wavy grass
  • Scientific names: Oplismenus undulatifolius

Classification in Wisconsin: Prohibited

Ecological Threat
  • The species invades temperate environments and is typically found in full-canopy hardwood forests, forest margins and shady riparian zones. It has been recorded in the coastal plain, piedmont and montane regions.
  • It spreads rapidly over the forest floor decreasing plant diversity and providing little to no value for wildlife.
  • Once established, it prevents the regeneration of native hardwood tree species. Furthermore, it forms a dense layer in the forest understory and crowds out native herbaceous plants.
  • Because this species is new to North America, early detection and control are essential.
  • It appears to tolerate a wide range of soil pH.
  • The species can regenerate both vegetatively through stolons and from seeds. Stands of the species can produce upwards of 1,000 seeds per square meter per year.
  • It is known to out-compete the invasive plant garlic mustard.
Identification

Leaves & stems: Stems and leaves (upper and lower sides) are covered in scattered hairs about 1-2 mm long. Leaves have horizontal ripples or undulations across their width, tapering to an elongated sharp point. Leaves remain green late into fall.

Flowers: Blooms from mid-September to November.

Fruits & seeds: Forms spikelets with long sticky awns, which readily adhere to passing animals, greatly enhancing seed dispersal.

Roots: This grass is a shallow-rooted perennial with spreading stolons that grow several feet long.

Similar species: Wavy leaf basket grass is similar in appearance to Japanese stilt grass (Microstegium vimineum; invasive). Any sightings of either species should be reported immediately since they are not currently present in Wisconsin.

Distribution

There have been no reports of wavy leaf basket grass in Wisconsin. Have you seen it? Please send us a report

Control
Mechanical:
  • Because the species has shallow roots, it can be easily hand-pulled, which is thought to be more effective than chemical treatment. Be sure to pull the entire plant, including the seeds. Double bag and seal all plant material.
Chemical:
  • Apply herbicide as a foliar spray. Chemical treatment includes an application of 1-2% solution of glyphosate. Roundup works well later in the year, while a grass-specific herbicide is more effective early in the season.
Resources
Sources for content:
  • U.S. National Early Detection and Rapid Response System for Invasive Plants
  • The Global Invasive Species Database, ISSG, ICUN.
  • National Park Service. Invasive Exotic Plant Factsheet, Wavyleaf basketgrass (Oplismenus hirtellus ssp. undulatifolius).
  • USDA Animal and Plant Health Inspection Service. Weed Risk Assessment. 2012.
  • Virginia Department of Forestry
Links for more information: