Yellow Nutsedge

Invasive: 

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.

 

 

 

 

 

 

 

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. 

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. 

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.

DO:

• 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.

DO NOT:

• 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.

Control

Mechanical 

• 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.

Chemical

• 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.

Biological

• There are currently no available biocontrols in Canada.

Integrated Control

• A combination of crop rotation and herbicide treatments will help decrease population densities.