Juncus tenuis Willdenow. Subgenus: Agathryon. Section: Steirochloa. Phen: Jun-Sep. Hab: Dry or moist soil along roadsides and paths, fields. Dist: NL (Labrador) west to AK, south to FL, TX, CA, and n. Mexico; Central and South America; introduced widely around the world.
ID notes: Similar to J. anthelatus but the heads are more congested on shorter inflorescence branches. Distinguished from J. dichotomus, J. dudleyi, and J. interior by the long membranous auricle.
Origin/Endemic status: Native
Taxonomy Comments: J. tenuis as it is here treated includes J. tenuis var. williamsii Fernald, which has a more congested inflorescence with arched to recurved inflorescence branches.
Synonymy: = Ar, ETx1, FNA22, Il, K3, K4, Mi, NcTx, NE, NY, Tn, Va, Kirschner (2002b), Kirschner (2002c); < Juncus tenuis Willd. – G, GrPl, GW1, K1, RAB, S, Tx, W, WH3; < Juncus tenuis Willd. var. tenuis – C, Meso6, Mo1, Pa, WV; > Juncus tenuis Willd. var. tenuis – F; > Juncus tenuis Willd. var. williamsii Fernald – F