Pl. 129 l;
A. tenuis Sibth.
Plants perennial, with rhizomes and sometimes also stolons,
forming clumps. Flowering stems 20–60 cm long, erect to spreading, often
ascending from spreading bases. Leaf sheaths glabrous, the ligule 0.5–2.5 mm
long, mostly shorter than wide, truncate at the tip. Leaf blades 2–12 cm long,
2–6 mm wide, flat or folded, somewhat roughened, green to dark green.
Inflorescences 4–15 cm long, open panicles, erect, the main branches loosely
ascending to spreading, branched again below the middle, all naked (without
spikelets) toward the base, glabrous. Glumes 1.5–3.0 mm long. Lemma 1.4–2.5 mm
long, narrowed to the slender tip, sharply pointed or truncate at the very tip,
usually somewhat roughened toward the tip, awnless or with a slender straight
awn, this 0.5–2.0 mm long, shorter than the spikelet. Palea relatively well
developed, 1/2–2/3 as long as the lemma, 2‑nerved. Stamens 3, the anthers
0.5–1.5 mm long. Fruits 1.0–1.4 mm long, reddish brown. 2n=28–35.
Introduced, uncommon and widely scattered in the state (native
of Europe; cultivated and escaped sporadically in the northern U.S. and Canada). Roadsides, railroads, and open, disturbed areas.
Agrostis capillaris is cultivated as a turf grass for lawns. The correct name
for this species remains controversial. The original description by Linnaeus of
A. capillaris contained elements of five different species, including
the present taxon. Several authors, including Philipson (1937), have suggested
that it is thus of uncertain application and should be rejected under the
International Code of Botanical Nomenclature. Under this interpretation, A.
tenuis becomes the oldest validly published name. However, Widén (1971),
who reviewed the situation regarding nomenclature and typification, rejected
this argument because most authors have continued to apply the name A.
capillaris in a consistent fashion. He lectotypified (selected a type for
the species from among the materials available to Linnaeus) the name A.
capillaris to stabilize its application to plants of the present taxon.
According to the International Code, this must be followed unless a proposal is
approved in the future to officially reject the name A. capillaris.