Apera is a small genus of annual grasses in the family Poaceae, commonly known as silkybent grasses or windgrasses. The genus comprises a handful of species native to Europe, North Africa, and parts of Asia, and has been widely introduced and naturalized across North and South America, where several species occur as weeds of arable land and disturbed habitats.
Plants in the genus are slender, upright annuals producing open, delicate panicles with fine, silky spikelets — a feature that gives rise to the common name "silkybent." The most widespread and economically significant member is Apera spica-venti (loose silkybent or common windgrass), which ranges from the Canary Islands north to Denmark and east to Yakutia, and has naturalized in the United States, Canada, and the Russian Far East. Apera interrupta (dense silkybent or interrupted windgrass) has a similarly broad Eurasian and North African distribution and has also naturalized in Argentina, Chile, and North America. Several additional species — including Apera intermedia, Apera baytopiana, and Apera triaristata — are more restricted, occurring primarily in Turkey and the surrounding region.
Distribution
Apera is native to Europe, North Africa, and parts of Asia, with its range extending from the Canary Islands and Portugal across to Yakutia and Central Asia. Species such as A. spica-venti and A. interrupta have been introduced and naturalized in North America (United States and Canada), South America (Argentina and Chile), and parts of the Russian Far East.
Taxonomy Notes
The genus Apera belongs to the family Poaceae (grasses). Several species formerly placed in Apera have been transferred to other genera including Agrostis, Anemanthele, Dichelachne, Muhlenbergia, and Sporobolus.
