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Pest SolutionsPESTS + WEEDSUSING PESTICIDES OR HERBICIDES?
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Nutsedge
Cyperus esculentus and Cyperus rotundus
Updated Apr 16, 2026
Make a Positive Identification
- Nutsedges are weeds in yards, gardens and agriculture.
- Nutsedge leaves are stiffer than lawn grass, and arranged in sets of three. They grow from a triangular base.
- Nutsedge spreads aggressively by underground tubers, and sometimes by seed.
- Seedlings and sprouts from tubers look similar to the mature plant.
Yellow Nutsedge
Species: Yellow nutsedge
Ohio State Weed Lab, The Ohio State University, Bugwood.org
Yellow nutsedge (Cyperus esculentus) leaves are light green. Narrow leaves grow up to 12 inches long and have pointed tips as shown in the photo. Stems grow up to 3 feet tall from a triangular base.
Species: Yellow nutsedge
John Cardina, The Ohio State University, Bugwood.org
Yellow nutsedge flowers (spikelets) and seeds are light brown to golden.
Species: Yellow Nutsedge
Howard F. Schwartz, Colorado State University, Bugwood.org
Mature yellow nutsedge tubers are up to ½ inch wide, round, smooth and brown-black. A single tuber forms at the end of a rhizome.
Purple Nutsedge
Species: Purple Nutsedge
"Cyperus rotundus" by anpingwater is licensed under CC BY-NC 4.0
Purple nutsedge (Cyperus rotundus) leaves are dark green with rounded tips. They grow 2 - 6 inches long. Stems grow up to 1 - 2 feet tall from a triangular base.
Species: Purple Nutsedge
"Cyperus rotundus" by chiuluan is licensed under CC BY 4.0
Purple nutsedge flowers (spikelets) are red to purple. The seeds are dark brown or black.
Species: Purple nutsedge
Mature purple nutsedge tubers are up to 1 inch wide with red-brown scales. The tubers grow in chains on a single rhizome.
LOOK-ALIKES: OTHER NUTSEDGE SPECIES
Species: Other Nutsedge Species
There are several other weedy and many native species of nutsedge in North America.
It takes a special identification key and training to tell the species apart.
Control methods for all nutsedge species are the same.
Your local Extension Specialist in Oregon and other states can help you identify plants on your property.
Nutsedge Benefits
- Yellow and purple nutsedge tubers are edible.
- Cultures around the world use them as a food source.
- Hogs dig and eat the tubers.
Only eat wild edible plants you correctly identify. Only eat nutsedge tubers from your own property. Don’t eat nutsedge tubers that have been sprayed with chemicals or growing on roadsides.
Nutsedge Risks
- Nutsedges form a dense mat of stems and leaves if left un-managed.
- They exclude other garden and landscape plants.
- They become a nuisance in lawns by replacing grass.
Risk Card
Does it cause harm?
Adults & Children
Low
Property
Some
Pets
None
Annoyance
High
Difficult to control
Environment
Some
Action Recommended
TAKE ACTION
Nutsedge is an invasive weed. It spreads quickly via tubers and rhizomes.
If you have nutsedge in your garden or on your property, take action to control its spread. Report infestations of purple nutsedge.
Do I need to take action?
Yes. Remove individual plants and patches. Nutsedges spread aggressively and are difficult to control.
What if I do nothing?
Nutsedge forms dense mats and is difficult to control. The longer you wait to act, the more difficult it will be to control it.
PREVENT NUTSEDGE
Howard F. Schwartz, Colorado State University, Bugwood.org
Look for Nutsedge Leaves Following Control Activity
- Return to the site after control activities and look for regrowth. It regrows from underground rhizomes and tubers. Take action as needed.
- Look for young nutsedge growth in spring and early summer, as shown in the photo..
- Large, established patches of nutsedges will require several years of follow-up monitoring and treatment.
Weston Miller, Oregon State University
Remove Soil from Shoes and Equipment
- After working or traveling in a patch of nutsedge, clean your boots and tools. Use a wire brush to remove soil and seeds.
- If you drive through patches of nutsedge, clean your vehicle.
Weston Miller, Oregon State University
Install New Plants
- Take care of the plants to get them established and suppress nutsedge regrowth.
- Replanting stabilizes the soil surface, shades young nutsedge plants, and creates wildlife habitat.
- Nutsedge prefers wet conditions. Improve soil drainage to reduce the wet conditions that favor nutsedge growth.
- Don't bring nutsedge tubers to your site with garden amendments such as compost. Tubers may also be in soil with potted nursery plants
SOLUTIONS FOR NUTSEDGE
Early Detection & Rapid Response
- Nutsedges are difficult to control if they are allowed to get established.
- Watch for nutsedge on property you manage. Remove it before it becomes a bigger problem.
- Prevent establishment by removing small plants before they develop tubers.
Physical Removal of Plants & Non-chemical Methods
- Reduce patches by digging out plants by the roots and rhizomes.
- Screen soil for roots, rhizomes, and tubers.
- Dispose of nutsedge stems, roots and tubers in the trash or landfill.
Herbicides (Weed Killers)
- Herbicides effectively control nutsedges when used according to the label instructions.
Monitoring & Follow Up
- Nutsedge will grow from rhizomes and tubers left in the soil. It rarely grows from seed.
- Following removal, return to the area every few months. Look for regrowth and seedlings. Take action as needed.
- Established plants require several years of follow-up control actions.
NEED HELP?
Consider a licensed pest control company. Learn How to Hire a Pest Control Company.
Your local Extension Specialist in Oregon and other states can suggest other methods.
Jump to
| Method | Does it work? | Is it safe? | Recommendation |
|---|---|---|---|
A Physically Remove Plants |
Effective |
Low risk |
Recommended |
B Manage with Herbicides |
Effective |
Moderate risk |
Use if Necessary |
|
C If Using Herbicides, Protect Yourself and Minimize Risks
|
A
Physically Remove Plants
Non-Chemical Method
Weston Miller, Oregon State University
Physically Remove Plants
Recommended
- Dig out plants.
- Regularly cut or mow leaves.
- Cultivate and expose tubers to warm drying conditions. Withhold irrigation.
- These steps will weaken and kill tubers on the soil surface and reduce patch vigor.
- Assume there will be regrowth following control activities.
| Does it work? | Effective |
| How much effort? | High effort Established plants require several years of follow-up control actions. Following removal, return to the area every several months. Look for regrowth and seedlings. Take action as needed. |
| What's the risk? | Low risk |
| Possible risk of exposure or harm from chemicals | NONE |
Steve Dewey, Utah State University, Bugwood.org
Weston Miller, Oregon State University
Soil Disturbance and Erosion
- Digging out large patches of nutsedge plants creates significant soil disturbance.
- Minimize soil disturbance as much as possible.
- Take steps to prevent erosion as needed.
- Replant the area to shade nutsedge sprouts.
B
Manage with Herbicides
Chemical Method: Use with caution
Chameleonseye, iStock
Manage with Herbicides
Use if Necessary
| Does it work? | Effective
|
| How much effort? | Moderate effort
|
| What's the risk? | Moderate risk
|
| Possible risk of exposure or harm from chemicals | Using herbicides includes some amount of risk. The lowest risk comes with using alternative methods. You may be exposed to an herbicide if you:
Follow directions closely to reduce risk. |
Some herbicides are available for home use. A few are listed below. These active ingredients are available alone or in products containing more than one. They are effective chemical treatments for nutsedge. Look for these chemical names in the “Active Ingredients” section of product labels.
- Glyphosate, Isopropylamine salt
- Sulfentrazone
- Diquat dibromide
- Ammonium nonanoate
- Bifenthrin
Suggested active ingredients are from the Pesticide Information Center Online (PICOL) Database. They are permitted for HOME use in Oregon. Read the label for application directions and effectiveness information.
ONLY professional pesticide applicators can use Restricted-Use Pesticides (RUP) that may be more effective. For larger stands of nutsedge contact a licensed pesticide applicator with experience controlling nutsedge.
Herbicide Application Tips
- Premixed products are available in hardware stores and garden centers.
- Most of these ingredients will damage most plants and grasses. Don’t let the spray contact plants you want to keep.
- Apply herbicide to nutsedge when it is actively growing in spring and early summer. Apply before the plants have 5 or more leaves.
- Expect that nutsedges will regrow after treatment with herbicides. Look for regrowth and re-treat as needed.
- Herbicides have a limited impact on tubers. Applying herbicide to early growth and repeated applications are important.
- It takes repeated efforts over several years to get rid of a well-established stand of nutsedge.
Minimize the potential impact of herbicides to bees and other pollinators. Treat nutsedge plants before they flower. Or apply herbicides in the morning or evening when bees are less active. Avoid spraying pollinators directly. For more information, see OSU’s How to Reduce Bee Poisoning from Pesticides
If Using Herbicides, Protect Yourself and Minimize Risks
Chemical Method: Use with Caution
FangXiaNuo, iStock
Why is it important to read herbicide labels?
- They have detailed information on how to use the product correctly and legally.
- They contain information on potential hazards of the product.
- They provide instructions you should follow for poisonings and spills.
- Following label instructions helps to minimize the risks and maximize the benefits.
Key Herbicide Safety Tips
- Read the entire label front to back.
- Follow the instructions.
- Review the instructions even for brands you know.
- Only apply the product where the label says it may be applied.
- Be precise in your application. More is not better.
The Label is the Law
ALWAYS read the label before using herbicide products. The label is a legal document that provides information on how to safely use the herbicide. It includes required personal protective gear and application methods. This helps avoid harm to human health and the environment. Using an herbicide in ways not listed on the label is illegal. It can result in legal enforcement actions.
READ THE LABEL & Follow Instructions
It has instructions to protect you and the environment.
- Labels are different for every product and they often change over time.
- Use a magnifying glass for small print.
- Pay attention to CAUTION, WARNING, and DANGER statements.
- Pay attention to the PRECAUTIONARY STATEMENTS.
- The law states you must read and follow herbicide instructions.
Protect Yourself
Eye, skin & lung irritants
- Wear the right protective gear. This often includes, but is not limited to: a long-sleeved shirt, pants, socks, closed shoes, safety glasses, and chemical-resistant gloves.
- Mix outdoors or in a well-ventilated area.
- Wash hands after mixing or applying, and before eating or smoking.
- Take a shower immediately after handling herbicides.
- Wash clothes worn while mixing or applying separately from other laundry.
Protect Children & Pets
Children and pets are at risk if they eat or touch the plants before they dry.
- Keep them away during and after applying herbicides (read the label for how long).
- Remove toys and pet dishes from the yard before applying.
- Don’t track herbicide products into your home on shoes or clothes.
Protect Pollinators
- Apply in the early morning or evening when bees are less active.
- Kill weeds before they flower. Avoid spraying flowering plants.
- Do not spray on bees or insects.
Protect Plants You Want to Keep
- Glyphosate and other broad-spectrum herbicide ingredients can damage both grass and broadleaf plants.
- Minimize spraying of foliage, stems, exposed roots, or the trunks of desirable shrubs or trees to avoid harm.
- Follow the label to avoid damaging the roots of trees and shrubs.
Avoid Wet, Windy, or Hot Weather
Use during favorable weather for best results.
- Don’t spray when it’s raining or when rain is expected in the next 24 hours.
- Wind causes the spray to drift, which can get on you and desired plants.
- Herbicides may be less effective in hot weather if the target plants are moisture-stressed.
- Some herbicides can turn into a vapor in hot weather and damage nearby plants.
Don’t Spray into Water
- It’s illegal to apply herbicides in a stream or slow-moving/wetland pool.
- You need a product registered for aquatic areas. This includes waterways, ditches, drains, and other places where water collects.
Storage & Disposal
- Store in a secure area away from children.
- Don’t put unused herbicide products in the trash.
- Never pour down any drain or waterway.
- Take unused herbicides to a hazardous waste facility.
Call 1-800-CLEANUP (1-800-253-2687) to find out where to dispose of herbicides.
For the Portland metro region in Oregon, contact Metro’s Recycling Information. Call 503-234-3000, email or visit Metro’s website
More about:
About Using Pesticides on School Grounds in Oregon
If using pesticides on school grounds, there are special rules in Oregon. See School Integrated Pest Management (Oregon Department of Agriculture).
NEED HELP?
The National Pesticide Information Center (NPIC) can answer questions about pest control chemicals.
1-800-858-7378 or npic@ace.orst.edu
Consider using a licensed pest or weed control company. Learn How to Hire a Pest Control Company.
Your local Extension Specialist in Oregon and other states can suggest other methods.
Invasive Species Alert
- Invasives are non-native species that spread aggressively and alter the environment.
- Controlling unwanted nutsedge is costly.
- Please do your part to control it on property you manage. Nutsedge can spread beyond your property and have an adverse impact on your neighbors.
If you think you’ve found purple nutsedge in the grey areas of this map, please report it to the Oregon Invasive Species Hotline at: 1-866-INVADER (1-888-468-2337) or use their online reporting form
Invasive species data @ 2022, iMapInvasives (NatureServe)
View Larger Map >
If you find purple nutsedge in a new area (orange shows already reported cases), please report it.
Content provided by editor Weston Miller, and writers J. Jeremiah Mann and Signe Danler. Pesticide safety information edited by Kaci Buhl.
Peer review facilitated by OSU Department of Horticulture.
Nutsedge (Cyperus spp.)
University of California IPM
Nutsedge Control
University of California IPM
Yellow Nutsedge
Washington State Noxious Weed Control Board
Purple Nutsedge
Washington State Noxious Weed Control Board
Yellow Nutsedge
Oregon State University Dept. of Agriculture