Photo credit: Andrew Rohrbaugh (DCNR Bureau of Forestry)
(Oplismenus hirtellus spp. undulatifolius)
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Species at a Glance
Wavyleaf basketgrass is an introduced subspecies of the native basketgrass (O. hirtellus (L.) P. Beauv.). It is a fast-spreading, perennial, understory grass that forms dense stands that can crowd out native herbaceous plants and threaten the deciduous forests of eastern North America.
Leaves: Flat, dark green leaves are about 1.2 cm (0.5 in) wide and 4-10 cm (1.5-4 in) long with rippling waves across the blades and elongated, pointed tips. The leaf sheaths and stems are noticeably hairy.
Fruits/Seeds: Seeds, which begin to appear in late summer, are covered with a glue-like substance that allows them to stick to other objects and organisms.
Stems/Roots: Stems are branching and covered in fuzzy hairs. Rooting occurs at the nodes of the stems.
While wavyleaf basketgrass resembles Japanese stilt grass (Microstegium vimineum), these species differ in that the leaves of Japanese stiltgrass have a silvery row of hairs running down the midvein and end in a blunt gradual point. Wavyleaf basketgrass leaves are rippled across their width and end with an elongated sharp tip.
Wavyleaf basketgrass is a shade tolerant species that avoids sunny environments. It is mainly found in shaded, moist, deciduous forests.
Wavyleaf basketgrass spreads quickly through rhizomes and seeds. The sticky substance on the seeds allows them to adhere to passing animals, people, or vehicles, easily spreading to new locations.
Native to Europe and Asia, it’s unclear how wavyleaf basketgrass was first introduced to the United States; however, it’s possible it was through contamination of hanging baskets. It was first found in Howard County Maryland in 1996. In 2000, it was found growing along a stream in Baltimore County, Maryland. Documented locations have also been found in Virginia.
Note: Distribution data for this species may have changed since the publication of the Mid-Atlantic Field Guide to Aquatic Invasive Species (2016), the source of information for this description.
This species can completely cover the forest floor, providing competition against native forest species. With the decrease in plant diversity, wavyleaf basketgrass also provides very little wildlife value. Because it is still relatively new in the United States, its ecological impacts are mostly unknown.
Information for this species profile comes from the Mid-Atlantic Field Guide to Aquatic Invasive Species (2016).