Native to Eurasia, but accidentally introduced to the rice-growing regions of California, and now a widespread weed in marshy habitats in California.
A perennial reproducing from seeds and propagating by long rhizomes. It is a problem along drainage and irrigation canals.
Mature plants are as tall as 3 feet, with thick stems that are sharply triangular in cross-section. Stems are leafless, but at their base is a short sheath that ends in a flattened point.
Flower heads form at the end of the stem, along with a pointed, leaf-like structure that comes off the stem at a sharp angle. Flower heads are open clusters of several spikelets, each on a short stalk or no stalk. Spikelets are elongate and pointed.
Characteristicts Important to Control:
Aggressively growing perennials that are found in marshy or aquatic habitats. Growth is from thick, strong rhizomes, making physical removal unlikely to be successful.