Town Crier Articles

Invader in Our Midst: Japanese Stiltgrass

Posted on April 1, 2020 7:00 AM by Patti Vaticano

We have an insidious invader in New Town, a deceptively pretty and even delicate foliage that sports bright, lime-green leaves on slender stems. This is Japanese Stiltgrass, also known as Eulalia or in Latin, Microstegium vimenium. If looks can be deceiving, then Stiltgrass is the proverbial wolf in sheep’s clothing, offering incursion tactics extremely hard to combat. Even where the grass has been established for a short time, it forms a dense mat of ground cover with leaves growing up to 40 inches long and rooting at the stem nodes, deadly to all other plant growth and efficiently preventing regeneration of forests, fields, and home gardens, thereafter. Within just three to five years, the plant creates impenetrable, single stands which crowd out native herbaceous vegetation with alarming precision, reducing the growth and flowering of native species, suppressing entire native plant communities, altering and/or overwhelming insect colonies, slowing plant succession, and altering nutrient cycling. Only the full eradication of Stiltgrass will assure the recovery of native species, both plant and insect, from the destruction that it brings.

This curious aggressor prefers moist soil that is shaded from full sun. It is found in marshes, ditches, low-lying woods, floodplains, woodland borders, damp fields, woodland thickets, lawns, and along stream sides and roadsides. Wet soils that have periods of standing water are not suitable for Japanese Stiltgrass. Regardless, its seeds can survive and germinate after extended periods of inundation. Although moderately prolific, with a single plant typically giving rise to as many as 1000 seeds, the seeds remain viable in the soil for three to five years, and the plant can spread rapidly, particularly following a disturbance such as flooding or mowing. An additional means of rapid growth of this grass is via the white tail deer, which, while not feeding on the grass itself, remove its competition by feeding on other native plant species of wood and field.

Proper identification of Japanese Stiltgrass is crucial in the war against growth. It’s lime-green leaves, four to five inches in length and half an inch wide, taper at both ends and should not be confused with Wavyleaf Grass, whose sheaths and stems are noticeably hairier than those of Stiltgrass. Waveyleaf Grass is also an invader, though with somewhat weaker abilities, and eradication of the two would require very different tactics. Stiltgrass is an annual plant, beginning its life cycle from a newly germinated seed each year. Waveyleaf grass, on the other hand, is a perennial that can reemerge from an established root system to spread its seeds. Recognizing these life cycle differences is key to establishing an effective control strategy for Stiltgrass.

Native to Asia from India to Japan, Japanese Stiltgrass was first discovered in this country in 1919, in the state of Tennessee. Since then, it has spread to all states east of the Mississippi and south of and including Connecticut. One of its uses in the Orient was as a packing material for porcelain from China, and this was, most likely, its means of introduction to our area. Japanese Stiltgrass is now found in every county in the Commonwealth.

For residents of New Town, this is not a problem we can solve ourselves, as the plant has appeared on private land and in environmentally sensitive areas. Possible methods of control may include biological controls as well as us of herbicide and manual removal. The LAC would like residents to know that the Committee is currently working with local and state agencies to formulate a control strategy. With better information, the LAC will develop a plan which will include a strategic method and the best season in which to implement it. More information from the LAC as to that method and its progress will be forthcoming.

Comments

Comment By: Edwin Elmore

Posted on April 1, 2020 10:58 AM

Where is it located in New Town?

Response from LAC Chair:
We have residents reporting stiltgrass in multiple locations. Most often it is found in natural areas and around our walking trails. Residents have also reported it in flower beds, presumably brought there by bird droppings. The seeds are quite small and can also be transported by animal fur and clothing. Our turf is frequently mowed and not an ideal place for stiltgrass to entrench.

All areas of James City County are reporting stiltgrass growth. William & Mary has the problem as well. As the article states, the NTRA will coordinate our response with local and state agencies.

Last Edited: 04/01/2020 at 04:24 PM