Rolland's bulrush - Trichophorum pumilum
Scirpus pumilus, Scirpus rollandii
Caespitose. Stems terete, 5–25 cm, clustered on thin rhizomes. Leaf blades ca. 0.5 mm wide. Spikelet 3–4 mm long with 3 to 6 flowers; awn of lowest bract shorter than the spikelet. Scales 2.5–3.5 mm long, glabrous, brown with a pale midstripe; tip rounded. Flowers: bristles absent. Achene 1.5–2 mm long (Lesica et al. 2012. Manual of Montana Vascular Plants. BRIT Press. Fort Worth, TX
Fruiting in July.
After mid-summer, Trichophorum pumilum
looks like a tiny stick with a few little black eggs glued on top. It is most likely confused with species of Eleocharis
, but in these species, the base of the style is enlarged, and the scales are persistent. Trichophorum cespitosum
is a larger plant that forms distinctive tussocks. A hand lens will be necessary for positive identification.
In botanical keys,Trichophorum pumilum
and Amphiscirpus nevadensis
may key closely.Rolland's Bulrush
- Trichophorum pumilum
, Native, SOC
*Perianth Bristles: 0; absent.
*Achene: Tipped with a skinny, short beak (style). Subtended by a scale.
*Spikelets: Solitary, 3-7 mm long. Spikelet is not subtended by a leaf-like bract.
*Stems: Round, less than 15 cm tall.
*Leaves: Less than 0.5 mm wide.
*Habitat: Hummocks in calcareous fens.Nevada Clubrush
- Amphiscirpus nevadensis
, Native, SOC
*Perianth Bristles: 1-6, inconspicuous and shorter than the achene.
*Achene: Not tipped with a beak; style absent. Subtended by a scale.
*Scales: Awn absent.
*Spikelets: Solitary, but usually some plants have at least 2 spikelets; 6-12 mm long. Always with 1 long, leaf-like bract below (subtended) the spikelets.
*Stems: Round, wiry, and erect. Lacks internal cavities.
*Leaves: Basal and on lower stem, 0.5-2.0 mm wide.
*Habitat: Moist to wet alkaline wetlands, but not aquatic.
Calcareous fens in the foothills.