Weed Seed - Yellow Bluestem (Bothriochloa ischaemum)
Since its initial finding in the United States, yellow bluestem has spread over much of the southern United States. Yellow bluestem can crowd out native grasses and has negative effects on ecosystem biodiversity.
Where it's found
Yellow bluestem has not been found in Canada. It is native to Asia and southern Europe, and has been introduced into the Caribbean, Mexico, parts of South America, and the United States. Typical habitats include roadsides, waste places, rangelands and pastures.
What it looks like
Yellow bluestem is an erect, slender, perennial grass that typically reaches 30–80 cm tall. A notable feature of this species is its reddish-purple, spiky seed heads, which are 5–10 cm long. Nodes, where the leaves emerge, become brown to purple with maturity, and stems turn from light green to yellow.
How it spreads
Yellow bluestem can spread as a seed and grain contaminant and in association with road construction and maintenance. Often abundant along roadsides, it tends to spread outwards from roadsides and into new areas. Yellow bluestem establishes easily from seed. Seeds can survive a long time in the soil.
Legislation
Yellow bluestem is listed as a prohibited noxious weed on the Weed Seeds Order, 2016 under the Seeds Act. Its presence in domestic and imported seed for planting is prohibited.
What you can do about it
- Use clean grain, hay and straw.
- Maintain healthy and diverse pastures.
- Use clean, high-quality seed that is certified if possible.
- Contact your local Canadian Food Inspection Agency (CFIA) office if you suspect you have found this invasive plant. The CFIA will follow up and determine if further action is needed.
Learn more about invasive species.

Bob Harms, University of Texas

Bob Harms, University of Texas

Bob Harms, University of Texas