- Yellow Nut-grass
- Earth almond
- Edible Nutgrass
- Northern Nutgrass
- Rush Nut
- Tiger Nut
General: Yellow Nutsedge is a perennial herb from the Cyperaceae (Sedge) family.
Flowers: Inconspicuous flowers are arranged into numerous, narrow, straw-coloured clusters within a branched, umbrella-shaped flower head at the end of the stem. Each cluster contains 5 – 16 spikes, which grow perpendicular to the flower stalk.
Stems: Are unbranched, smooth, and 0.1 – 0.9m tall, with a triangular cross-section.
Leaves: Grass-like leaves are yellow to green and elongated (3 – 8mm wide) with a distinct mid-vein and a pointed tip. Leaves are typically clustered at the base of the plant.
Seeds: Underground structures include fibrous roots, rhizomes, tubers and bulbs. Notably, tubers are white, smooth and almond-flavoured.
Roots: Are one-seeded, oval and yellowish-brown.
Purple Nutsedge (Cyperus rotundus) can be distinguished by its generally darker leaves and red-brown to purple flower clusters. Tubers are dark, taste very unpleasant, and attached to a wiry rhizome.
Habitat and Origin
Yellow Nutsedge was introduced from Europe. Since 1950, it has been considered one of the world’s worst weeds, as it is currently found on all continents except Antarctica.
The plant prefers well-drained and sandy soils. It occupies riparian areas, wet fields, irrigated crop fields, roadsides and ditches. It is classified as a pioneer species and can quickly colonize recently disturbed areas.
Propagation & Vectors of Spread
Yellow Nutsedge spreads by rhizomes, tubers, and occasionally seed. Tubers can remain viable in the soil for up to 4 years and can regenerate new plants. Plant patches are known to extend 1 metre per year.
Local dispersal occurs primarily through rhizomes, tubers and bulb growth. However, long-distance dispersal occurs when seeds are transported by wind, agricultural and nursery activities, soil movement, and water.
Ecological, Economic, & Health Impacts
- Outcompetes native vegetation, forming dense monocultures.
- Can transmit pests and diseases.
- Decreases amenity values.
- Can impact tourism.
- Reduces resource availability for crops, reducing crop yields.
What Can I Do?
Yellow Nutsedge is not yet found in the Sea to Sky, so PREVENTION is key:
Learn to identify Yellow Nutsedge: use the images presented on this profile page to learn how to identify Yellow Nutsedge.
What to do if you spot it: You can report any Yellow Nutsedge sighting by clicking here.
- Regularly monitor properties for weed infestations.
- Minimize soil disturbances and promptly revegetate disturbed areas to prevent the growth of Yellow Nutsedge.
- Check wildflower mixes to ensure that they do not contain Yellow Nutsedge.
- Ensure all flowering heads or buds are bagged or covered to prevent spread during transport to designated disposal sites.
- Unload, park or store equipment or vehicles in infested areas; remove plant material from any equipment, vehicles or clothing used in such areas and wash equipment and vehicles at designated cleaning sites before leaving infested areas.
- Plant Yellow Nutsedge in a garden, no matter how well-contained its enclosure may seem.
- Compost any flowering heads or buds. Instead, dispose of Yellow Nutsedge in the general/household waste stream at the landfill as the seeds will be able to persist the composting process.
- Move soil, gravel, or fill that has been contaminated with Yellow Nutsedge.
- Removal may prove challenging due to its layered root system.
- Prevent plants from developing tubers by removing young plants as soon as possible.
- If plants have already formed tubers, then dig 20 – 30 cm into the soil to remove roots.
- Glyphosate has proven effective on Yellow Nutsedge infestations.
- We recommend that any herbicide application is carried out by a person holding a valid BC Pesticide Applicator Certificate. Before selecting and applying herbicides, you must review and follow herbicide labels and application rates; municipal, regional, provincial and federal laws and regulations; species-specific treatment recommendations, and site-specific goals and objectives.
- There are currently no available biocontrols in Canada.
- A combination of crop rotation and herbicide treatments will help decrease population densities.
- E-Flora, Introduction to Vasvular plants, http://linnet.geog.ubc.ca/Atlas/Atlas.aspx?sciname=Cyperus%20esculentus%20var.%20leptostachyus
- Fraser Valley Invasive Species Society, Yellow Nutsedge, https://www.fviss.ca/invasive-plant/yellow-nutsedge
- Government of BC, Invasive Species Alert, https://www2.gov.bc.ca/assets/gov/environment/plants-animals-and-ecosystems/invasive-species/alerts/yellow_nutsedge_alert.pdf
- Government of BC, Field guide to Noxious Weeds, https://bcinvasives.ca/wp-content/uploads/2021/02/Field_guide_to_Noxious_Weeds_11th_2021.pdf
- Ohio State University, Ohio Perennial and Biennial Weed Guide, https://www.oardc.ohio-state.edu/weedguide/single_weed.php?id=84
- Plants For a Future, Cyperus esculentus, https://pfaf.org/user/plant.aspx?LatinName=Cyperus+esculentus