Stiltgrass: Remove ASAP!

If you’ve been noticing a sneaky bamboo-leaved grass creeping through your flower beds, veggie patches, or wooded paths, chances are you’ve met stiltgrass (Microstegium vimineum). It’s an nonnative annual that quickly smothers native plantings.

Stiltgrass can be distinguished from native look-alikes by the white line down the middle of the each blade.

Distribution range of Microstegium vimineum. Kartesz, J.T., The Biota of North America Program (BONAP). 2015. North American Plant Atlas. (http://bonap.net/napa).

Why Now?

Late summer is crunch time. Once stiltgrass drops its seeds, it’s like sending out party invitations for next year’s invasion. But the good news? It’s super easy to pull out by hand. The roots are shallow, so pulling barely disturbs the soil. At the residential level, there’s no need for herbicides—your gloved hands are just as fast.

The early morning dew gives stiltgrass leaves a blue hue making them standout amidst these violet leaves.

Stiltgrass Tips

• Go low: If stiltgrass is growing up through other plants, crouch down, and grab the stiltgrass at ground level. Pulling from the bottom is way more efficient than tugging from the t op.

• Get to know your stems: You can double your weeding efficiency by recognizing the stems of different plants. See this blog post.

• Early Morning Dew: In the morning, dew gives stiltgrass leaves a blue sheen making them easy to spot.

• Bundle it up: For big patches, just scrape your gloved hand across the soil and gather bundles of stiltgrass like gathering hair into a ponytail.

• Dry it out: Toss pulled stiltgrass onto your driveway or a sunny spot to dry. If you’ve caught it before it seeds, it makes an ideal straw mulch—perfect for woodland paths or veggie garden beds.

• Mowing Magic: If a large stand of stiltgrass has taken over an area, mowing or string trimming right before the seedheads form can knock back the population.

Dried stiltgrass, gathered before it goes to seed, is an ideal much for woodland paths.

Why It Matters

In the summer of 2023, there were a few stiltgrass plant (bottom of photo) which I removed from an otherwise clean native planting.

Here's the same garden area the following summer. Unable to get out into the garden, a year later the seed bank populated and smothered the entire bed.

Stiltgrass might look harmless, but its rampant growth overtakes native plants during the growing season. Worse yet, stiltgrass is allelopathic--it releases chemicals into the soil that inhibit the germination and growth of native plants. Its dead stems smother native plants beneath it. With each stiltgrass plant having the potential to produce 1,000 seeds, a little effort now means a lot less weeding in upcoming years!

So grab your gloves, cue up a garden playlist, and make it a satisfying afternoon of reclaiming your space.

Nature's Action Guide

Find more strategies for dealing with aggressive nonnative plants, check out Nature's Action Guide, Action 4: Remove Invasive Plants.