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Montana Field Guide

Montana Field Guides

Threadleaf Beakseed - Bulbostylis capillaris

Status Under Review
Native Species

Global Rank: G5
State Rank: SU

Agency Status
MNPS Threat Rank:

External Links

General Description
Cespitose annuals. Culms to 30 cm, bases soft. Leaves spreading to ascending, ¼–1/3 length of scapes; sheath borders tan, backs prominently ribbed, glabrous; blades filiform, 0.5 mm wide, involute, margins ciliate-scabrid, surface glabrous. Inflorescences solitary or more commonly in simple, open, rarely compact, involucrate anthelae; scapes filiform (rarely with several spikelets sessile or subsessile at plant base), prominently ribbed, glabrous; proximalmost involucral bract cuspidate or setaceous bladed, exceeding or exceeded by inflorescence. Spikelets 3-5 mm, red-brown, ovoid to lanceoloid; fertile scales ovate, 1.5–2 mm, apex acute, glabrous or distally puberulent, keel prominent, short-excurrent. Flowers: stamens (1–)2; anthers 0.5-0.7 mm, oblong-elliptic. Achenes ca 1 mm, trigonus-obovoid, rugose, yellowish to pale brown (adapted from Kral, 2003, Fl. North America, Vol. 23).

Range Comments
Widespread but highly sporadic across much of North America; more common in the east and nearly entirely absent from Rocky Mountains and Great Basin regions (Kartesz 2009).

Prairie, sandy outcrops and gravelly waste areas.

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Citation for data on this website:
Threadleaf Beakseed — Bulbostylis capillaris.  Montana Field Guide.  .  Retrieved on , from