Juncus tenuis (Path Rush)

Juncus tenuis

Juncus tenuis Willd.

Juncus macer Gray

Juncus tenuis Willd. var. multicornis E. Mey.

Juncus tenuis Willd. var. williamsii Fernald

Path Rush, Slender Rush, Field Rush, Poverty Rush, Wiregrass

Kingdom	Plantae	Plants, but not fungi, lichens, or algae
Subkingdom	Tracheobionta	Vascular plants—plants with a “circulatory system” for delivering water and nutrients
Division	Magnoliophyta	Flowering plants, also known as angiosperms
Class	Liliopsida	Monocots (plants with a single seed leaf); includes the lily family
Subclass	Commelinidae	Dayflowers and spiderworts, and several others
Order	Juncales	Rushes, sedges, and other grasslike plants
Family	Juncaceae	Rush family
Genus	Juncus	Possibly from Latin jungere, “to join or bind,” because the stems were used for binding
Species	tenuis	“Slender”

About plant names...

Path rush is native to and found throughout North America. It prefers full sun to light shade, and clay-loam or gravelly soils and a wide range of wetness.

Plants: Path rush, so-called because it is tough enough to grow right in the middle of trails, is easy to miss at first, looking like grass from a distance. But it is very common. Path rush is less than 12" (30 cm) high.

Leaves: Leaf blades are basal, and very thin, resembling pine needles, but up close they are narrow and flat, sometimes rolled slightly at the edges, resembling a slice of celery in cross-section. The blades are hairless, ~¹/₃₂" (0.5-1 mm) wide, and medium green in color, darkening later in the season.

Flowers: Tiny light greenish flowers consist of three petals and three sepals. They look nearly identical to each other, creating starlike flowers about ¼" (6.3 mm) around. Each petal and sepal is ¹/₁₆-³/₁₆" (3-5 mm) long. Flowers appear from April to May.

Fruits: Seed capsules are ovoid, about ¹/₁₆-³/₁₆" (3-5 mm) long and ¹/₁₆-⅛" (2-3 mm) around. The petals and sepals remain, now loosely wrapped around the capsule. Each capsule has three sections, a small point on top, and is filled with tiny seeds less than ¹/₃₂" (0.5 mm) long.

Online References:

Juncus tenuis at Illinois Wildflowers

Juncus tenuis on the New England Wildflower Society’s GoBotany site

Juncus tenuis at the Lady Bird Johnson Wildflower Center

Juncus tenuis on Wikimedia Commons