This week for Flora and Fauna Friday, we have an overgrown bushy-tailed grain-like wetland grass: Giant Bristlegrass (Setaria magna).
Giant Bristlegrass is a member of the Bristlegrass genus, Setaria. Bristlegrasses all share a similar growth habit: stiff flower stalks with widely spaced leaves that end in a bristly cylindrical cluster of seeds. The most famous of the genus, Foxtail Millet (Setaria italica) was domesticated more than 10,000 years ago and is still grown widely as a food grain throughout Asia. Here in the Lowcountry, we have three native species of Bristlegrass (Giant, Coastal, and Marsh) and two invasive species (Green and Yellow). Of those, four are relatively small and fairly innocuous grasses that, to the untrained eye, can easily be mistaken for one another. However the fifth, Giant Bristlegrass, stands out above the rest, literally.
Giant Bristlegrass can easily exceed six feet in height with a seed head a foot long and an inch and a half in diameter. Individual plants grow as clumps and often have a half-dozen or more seed heads at once. When several plants grow together, they can really standout above a marsh or wetland. They grow in brackish marshes in saturated soils and tolerate periodic salt intrusion well. Seed heads mature in late summer and fall. The seeds of Giant Bristlegrass provide food for resident rodents and songbirds and migrating sparrows during winter.
