Trying to ID fast, pervasive, weed in Clarksville wooded property.

Asked June 30, 2018, 2:49 PM EDT

Thin stalked plant, with narrow leaves organized singly along stalk. Explodes over all bare ground beds and between lawn grass plants very quickly every mid June. Very fast growing, shallow root. Generally 3-6 inches, but grows to about 2.5 feed if not pulled for long period. Initially single stalked, but stalk eventually branches if left to grow longer. Shallow roots make it easy to pull in the garden beds when its taller, except that it grows in such quantity and quickly. Difficult to deal with in lawn since its pervasive and between grass, so not physically reasonable to pull by hand. I am looking to name it and for a way of dealing with it, possibly one that that avoids herbicides -- in fact, not even clear it would respond to broad leaf killers. Have not tried. Advice appreciated. Thanks! J.

Howard County Maryland lawns and turf grassy weed invasives invasive weed stiltgrass plant care explosion of grassy weed

1 Response

This is Japanese stiltgrass, a foreign invasive weed which has been in Maryland for over a decade and is very fast-moving.

The best way to manage it in the lawn is by applying a crabgrass pre-emergent herbicide in early spring. See here for control and specific effective herbicides: https://extension.umd.edu/hgic/problems/japanese-stiltgrass

When mowing, be very careful not to shoot clipping into bed when the stiltgrass is going to seed (late summer/early fall).

In beds, weed by hand. Do not let it go to seed (late summer/early fall).

This is a terrible problem in our parks and natural areas. Manage it near these areas especially.

ECN