Achnatherum Lettermanii, or more commonly know as Letterman's Needlegrass, is a graminoid with green foliage and yellow flowers of the genus Achnatherum. It has a slow growth rate and a height of 2 feet at maturity. Its duration is perennial which means it will grow year after year. It's active growth period is spring summer fall, blooms during summer, is intolerant of shade and is routinely available commercially. Achnatherum Lettermanii or Letterman's Needlegrass's floral region is North America US Lower 48, specifically in the states of Arizona, California, Colorado, Idaho, Montana, New Mexico, Nevada, Oregon, Utah and Wyoming.
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