E-Flora BC: Electronic Atlas of the Flora of British Columbia

Trisetum spicatum (L.) K. Richt.
spike trisetum
Poaceae (Grass family)

Introduction to Vascular Plants

© Jamie Fenneman  Email the photographer   (Photo ID #4237)

E-Flora BC Static Map
Distribution of Trisetum spicatum
Click here to view the full interactive map and legend
Details about map content are available here
Click on the map dots to view record details.

Species Information

Click on the image below to view an expanded illustration for this species.

Perennial, tufted grass from fibrous roots; stems rough or short-hairy, 10-50 (70) cm tall.
Sheaths open, the basal sheaths short-hairy; blades folded to flat, minutely rough, 1.5-4 (5) mm wide; ligules usually hairy externally, finely jagged and more or less fringed with fine hairs, 0.5-2 (averaging 1) mm long.
Inflorescence a dense, spikelike, usually continuous but often interrupted, purplish, tawny or silvery panicle, 2-15 cm long; spikelets 2- to 3-flowered, nearly unstalked; glumes membranous, the lower ones averaging about (3) 4 (4.5) mm long, the upper ones mostly rough on the keels, 1/5-1/4 longer and about 1/2 again as wide, usually surpassing the lower florets and nearly equal to the upper florets; lemmas usually minutely rough, 4-5 mm long, bidentate, awned, the awns strongly abruptly bent, broadly spreading, arising up to 1.5 mm below the tips of the lemmas, 5-6 mm long; lodicules nearly entire to sharply lobed, about 0.7-1 mm long; anthers up to 1.5 mm long.
This is a highly variable species which cannot realistically be separated into infraspecific taxa. Even Hulten (1959), who recognized 14 subspecies in the T. spicatum complex, stated that "...the differentiation between the different taxa becomes somewhat arbitrary..." for our western cordilleran material.

Source: The Illustrated Flora of British Columbia

USDA Species Characteristics

Flower Colour:
Blooming Period:
Fruit/Seed characteristics:
Colour: Brown
Present from Summer to Fall
Source:  The USDA

Habitat / Range

Moist to dry, often rocky sites in all vegetation zones; common throughout BC although less frequent along the coast; circumpolar, N to AK, YT and NT, E to NF and S to ME, MA, PA, VA, TN, MN, SD, NM, AZ, CA and MX; Eurasia, S America.

Source: The Illustrated Flora of British Columbia


Ecological Framework for Trisetum spicatum

The table below shows the species-specific information calculated from
original data (BEC database) provided by the BC Ministry of Forests and Range.
(Updated August, 2013)

Site Information
Value / Class




Elevation (metres) 7 1787 3000
Slope Gradient (%) 0 26 230
Aspect (degrees)
[0 - N; 90 - E; 180 - S; 270 - W]
0 182 360
Soil Moisture Regime (SMR)
[0 - very xeric; 4 - mesic;
8 - hydric]
0 2 8
Modal Nutrient Regime
Number of field plots
 species was recorded in:
Modal BEC Zone Class
All BEC Zones (# of stations/zone) species was recorded in: AT(164), BAFA(288), BWBS(24), CDF(2), cma(11), CWH(3), ESSF(736), ICH(21), IDF(53), IMA(80), MH(23), MS(136), SBPS(70), SBS(53), SWB(50)


The climate type for this species, as reported in the: "British Columbia plant species codes and selected attributes. Version 6 Database" (Meidinger et al. 2008), is alpine tundra & boreal.

Synonyms and Alternate Names

Aira spicata L.
Trisetum molle Kunth
Trisetum montanum Vasey
Trisetum montanum var. shearii Louis-Marie
Trisetum spicatum subsp. alaskanum (Nash) HultΘn
Trisetum spicatum subsp. congdonii (Scribn. & Merr.) HultΘn
Trisetum spicatum subsp. majus (Rydb.) HultΘn
Trisetum spicatum subsp. molle (Kunth) HultΘn
Trisetum spicatum subsp. montanum (Vasey) W. Weber
Trisetum spicatum subsp. pilosiglume (Fernald) HultΘn
Trisetum spicatum var. alaskanum (Nash) Malte ex Louis-Marie
Trisetum spicatum var. congdonii (Scribn. & Merr.) Hitchc.
Trisetum spicatum var. maidenii (Gandog.) Fernald
Trisetum spicatum var. majus (Rydb.) Farw.
Trisetum spicatum var. molle (Kunth) Beal
Trisetum spicatum var. pilosiglume Fernald
Trisetum spicatum var. spicatiforme HultΘn
Trisetum spicatum var. villosissimum (Lange) Louis-Marie
Trisetum subspicatum (L.) Beauv.
Trisetum triflorum (Bigelow) A. L÷ve & D. L÷ve
Trisetum triflorum subsp. molle (Kunth) A. L÷ve & D. L÷ve
Trisetum villosissimum (Lange) Louis-Marie

Taxonomic and Nomenclatural Links

Additional Photo Sources

General References