Will Vinegar Kill Japanese Stiltgrass?

If you’ve ever visited a Virginia State Park to enjoy the outdoors and saw grasses that resemble the ones shown below, you might be viewing the highly invasive Japanese stiltgrass (Microstegium vimineum).

When a plant is invasive, it indicates that it will outcompete native plants in the region where it is growing and eventually take over. Invasive species can change the amount of food and resources available to other native organisms, which can have a devastating effect on our ecosystems.

Invasive Japanese stiltgrass is frequently found in disturbed regions, moist environments, close to bodies of water, and environments with a variety of light conditions from completely shaded to sunny. Japanese stiltgrass does not tolerate cold weather very well. Microstegium vimineum (Trin.) Camus, a.k.a. Japanese stiltgrass, n.d.

Justin Vollmer, a resource specialist for the Virginia Department of Conservation and Recreation’s (DCR) Potomac District, is investigating a different approach to controlling Japanese stiltgrass as a result. In late August, the Japanese stiltgrass could be destroyed using dry ice, halting further invasion for a few years.

The issue Vollmer has discovered with this approach is that because so much dry ice must be used to treat such a small area, it is not a practical way to get rid of Japanese stiltgrass. The dry ice may kill the stilgrass for up to three years, but the seed bank (dormant seeds in the soil) may persist for up to ten years, necessitating the use of second and even third applications of dry ice, raising the cost of the already pricey treatment.

One of the management strategies used at Leesylvania State Park is the removal of Japanese stiltgrass.

A much diluted solution (1/2% solution) of a common herbicide, such as Roundup, can be used to kill stiltgrass but won’t affect nearby flora, such as ferns, as other techniques that Vollmer discovered to be more effective at Virginia State Parks.

Additionally, vinegar can be used to treat Japanese stiltgrass. Because vinegar does not require a license, rigorous training, or protective equipment like other herbicides do, it can be administered by any authorized staff or volunteers. The vinegar shocks the soil with acidity, killing the stiltgrass, but can be metabolized by soil microbes so that an acidic soil is not produced.

There are options to assist Virginia State Parks with invasive plants like Japanese stiltgrass if you’re interested. Invasive species control in Leesylvania State Park and other Virginia State Parks, among many other crucial environmental chores, are offered seasonal opportunities with the Virginia Service and Conservation Corps program (part of AmeriCorps).

Is stilegrass killed by vinegar?

Invasive Japanese stiltgrass can drive out other grass species from your yard. Fortunately, removing it is simple;

1. Before it produces seeds, hand-pull any visible Japanese stiltgrass from your lawn. Be cautious when working with established plants because freshly planted Japanese stiltgrass loves disturbed soil. Since the grass has weak roots, you run the risk of overwatering the area before you even start to pick it out.

2. Mowing is an effective alternative because it stops the grass from producing seeds. Between August and the beginning of September is the ideal time to mow. Avoid cutting your grass too short since stiltgrass infestations may result. To prevent sunlight from penetrating the soil, mulch your lawn. This stops the seeds of Japanese stiltgrass from sprouting.

3. Maintain a lush, healthy grass. Make careful to fertilize and water properly.

4. Ordinary vinegar also aids; it lowers Japanese stiltgrass production by more than 80%.

5. For up to three years, dry ice kills stiltgrass and stops it from growing again. The seeds, though, survive and can slumber for up to ten years. Additionally, a tiny area of stilt grass will require a lot of dry ice to be treated, making it useless for a widespread infestation. When handling dry ice, use caution since it sublimates to carbon dioxide.

How can stiltgrass be removed naturally?

Public education’s gardener is Sonia Uyterhoeven. Join her every weekend for home gardening demonstrations in the Home Gardening Center on a range of subjects.

I went to a class on NOFA Organic Land Care’s organic treatment of invasive species in the landscape this past summer. I’d want to impart some of what I’ve learned, particularly in relation to the Japanese stilt grass (Microstegium vimineum), about which I wrote last week.

As an annual grass, the main objective is to stop Japanese stilt grass from generating seeds. Let’s examine how to utilize its life cycle to eliminate it.

Hand pulling is an alternative if you have a manageable or compact area of Japanese stilt grass. This annual grass has a prodigious capacity to produce seeds, which land in the soil seed bank. You must be careful when pulling the grass because physical removal can stimulate seed from past seasons to germinate and develop in the disturbed soil.

The optimum time is in the late summer, when the grass has begun to flower or has gone to seed, when it is tall and simple to grip onto. Fall is an excellent season to hand-pull crops since frost will kill any seeds that do develop in the soil before they have a chance to make seeds. Because the new plants that germinate will have time to generate another crop of seeds, pulling in the spring or early summer will result in twice as much effort for you. To safeguard your hands, don’t forget to wear gloves.

Mowing: Mowing or weed-whacking are effective solutions for vast areas. Before the grass blossoms and produces seeds, late in the season (August through early September) is the optimal time to use these techniques. Early in the season, the grass can be mowed, giving it time to rejuvenate, blossom, and produce seeds. Every year, before the young plants go to seed, the same area should be mowed to manage this issue.

Spraying: Another alternative for vast areas is to use a certified organic herbicide to spray. The issue with the majority of herbicides, organic or synthetic, is that they not only kill the targeted plant but also all other plants in the treated area, including those you want to keep.

The greatest time to spray is in the late summer, when the grass has just started to flower and has just finished spending a lot of energy growing. The facility won’t have sufficient energy reserves to recover for the season.

Burning is a last resort for those who are brave, cautious, and interested in pyrotechnics. This entails making an investment in a propane weed torch, learning how to use it properly, and, if required, securing a permission to carry out the work. The Nature Conservancy and the Connecticut Agricultural Station are places where you can receive training. Keep water nearby at all times in case the fire spreads.

Keep in mind that getting rid of any difficult weeds or invasive plants usually involves patience and repeated sprays. We’ll discuss how to maintain a space after removing invasive plants next week. You don’t want them to regrow after all this effort.

How is Japanese stiltgrass killed?

Postemergence herbicides work best when used prior to plant seed germination.

In gardens and planting beds, Japanese stiltgrass can be spot-treated with glyphosate and glufosinate (different trade names). Both of them are broad-spectrum herbicides that ought to be used solely on undesirable plants. Applying it to desired plants’ foliage, stems, or woody parts may also harm those parts.

Sethoxydim and Fluazifop-P-Butyl, two selective herbicides that can be used to control stiltgrass growth in landscaping beds, are sold under the trade names Bonide Grass Beater Over-the-Top Grass Killer and Ortho Grass B Gon Garden Grass Killer, respectively. These herbicides won’t harm the majority of ornamental plants that aren’t grass when applied as directed on the label. Pay great attention to the label and take all necessary precautions.

How can Japanese stiltgrass be eliminated without causing grass to die?

Because most chemical techniques, including a herbicide designed specifically for grasses like Clethodim, destroy turf grass, leaving a lawn with significant dead patches, killing Japanese stiltgrass in turf provides a unique difficulty. Fenoxaprop-p-ethyl, a herbicide that kills Japanese stiltgrass but NOT turf grass, is a suitable choice for killing stiltgrass in turf. The recommended application rate for this substance, Acclaim, is 0.4 oz./gallon plus 0.5% surfactant. In July 2020, this mixture was tried out successfully on five lawns in the Bloomington area. Turf grass remained untouched but stiltgrass perished after two to three weeks.

The blue flag in the image on the left delineates the boundary between the Acclaim-sprayed region to the right and the unsprayed area to the left. The stiltgrass on the left is robust and green, whereas the stiltgrass on the right has brown, curled leaves. Three weeks after spraying, this picture was taken. It should be noted that oftentimes a second spraying is required since after the initial spray, little plants hiding beneath other leaves may emerge.

Diluted vinegar: Does it kill grass?

One of the most prevalent liquids in kitchens, vinegar seems to have unlimited applications. A fast internet search will turn up thousands of uses for vinegar. People use vinegar for almost everything, from hair care to all-purpose cleaning, from medicine to disinfection. Therefore, it is not surprising that individuals are utilizing vinegar as a non-toxic substitute for conventional herbicides in their lawns and gardens. Household vinegar, which comes from the fermentation of alcohol, is non-toxic to humans, animals, and the environment. Where organic certification criteria are followed, it is very helpful.

Vinegar as a Natural Herbicide

While vinegar has been used as a herbicide for a very long time, the scientific evidence supporting vinegar’s effectiveness as a weed-killer has just recently come to light. Scientists from the Agricultural Research Service tested vinegar on some of the most prevalent weeds in 2002. They discovered that the weeds were eliminated within their first two weeks of life when vinegar was applied at average household strength concentrations (about 5 percent). Vinegar produced an 85 to 100% mortality rate at all growth stages at stronger doses (about 20%). Be cautious that solutions more than 11 percent can cause skin burns and should only be administered with proper clothes. Solutions higher than 5 percent vinegar should be handled carefully.

How to Use Vinegar as a Weed-Killer

Any form of vinegar will kill weeds, though white vinegar is typically the least expensive. Fill a spray bottle or pump sprayer with undiluted vinegar and use it freely on large weed patches. For areas like driveways, sidewalks, and other places where no vegetation is wanted, this spraying technique works well. Due to vinegar’s non-selective nature, it may harm any plant it comes into touch with, including grass and other desired plants like garden flowers. Use a paint brush to spot-spray weeds on your yard. Use an old brush to “paint the vinegar on the leaves and stems” of the weed you want to get rid of.

Other Tips for Using Vinegar

Vine works best on small, annual weeds with weak root systems, according to gardeners. It can take a few treatments to completely kill larger, perennial weeds. Apply on a sunny day with no breeze for optimal results. You will need to reapply if it rains within a day or two of your initial application. Although vinegar is an acid, it decomposes swiftly in the soil and is unlikely to have an impact on the pH values of the soil. According to some gardeners, using 1 oz. of liquid dishwashing soap per gallon makes vinegar more efficient at eliminating weeds.

How soon will weeds be killed by white vinegar?

A: Using commercial weed killers close to fruit or vegetable plants can raise safety concerns about some of the chemicals in such products. Is vinegar effective at killing weeds? You are fortunate. When used properly, vinegar can destroy weeds effectively. It is a natural herbicide and is equally safe to use while dressing a salad as vinaigrette. Additionally, vinegar comes in huge bottles that are affordable and practical for cooking and cleaning, so it is not a one-use item that will collect dust on a garage shelf.

Vinegar kills weeds quickly—usually within 24 hours—but it has no preference for the plants you want to grow or the weeds you want to destroy, so use it sparingly and under the correct circumstances. The concentration of the solution and the weather both affect vinegar’s effectiveness. A expert can handle the problem if the weeds are severe or if you are concerned about the integrity of your garden.

It’s best to leave some tasks to the experts. Get a free, no-obligation estimate from local, certified lawn service companies.