Deceptively beautiful, the emerging invasive Mexican feathergrass is a graceful, delicate and fine textured ornamental grass. It grows in a dense fountain like clump with slender leaves that roll tightly inward so that they appear wiry. It blooms in late spring with a greenish flower cluster that persists well into fall as it ripens to golden brown.
How does it spread?
Mexican feathergrass produces thousands of seeds, which are dispersed by wind, water or contaminated soil – as well as via automobiles and animal droppings. The seed-bank can persist for four years and the plant commonly self sows in California.
Where would I find it?
Nassella tenuissima grows on well drained soil and is drought tolerant. It is found in urban spaces, agricultural areas, forests, open grasslands, riparian zones, disturbed land, and shrublands.
What problems does it cause?
Mexican feathergrass often self sows abundantly and may spread out of its designated place in the garden. It is an extremely vigorous plant, which crowds out pasture species as well as native grasses in coastal areas.
In Argentina, where Mexican feathergrass is native, it is regarded as an unpalatable grass (Moretto & Distel 1998). The grass forms indigestible balls in the stomach of livestock and, if they are forced to graze the infected pasture, they may lose weight and die. Mexican feathergrass can become dominant under continual heavy grazing pressure with a low frequency of high-intensity fire (Distel & Boo 1995).