1. Cynodon dactylon (L.) Pers. (Bermuda grass)
Pl. 143 e,
f; Map 578
Plants perennial, creeping widely by stolons and rhizomes,
low‑growing and forming mats. Flowering stems 10–40 cm long, erect or
ascending at the tip from prostrate bases, glabrous. Leaf sheaths rounded to
slightly keeled on the back, hairy near the tip, the ligule a short membrane
with hairs along the margin. Leaf blades 1–8(–15) cm long, 1–4 mm wide, flat or
with the margins loosely inrolled, usually hairy toward the base.
Inflorescences with 3–6 spikes, these arranged palmately at the tip of the
axis. Spikes 2–6(–8) cm long, with numerous spikelets, these appressed in 2
rows along 1 side of the slender, flattened or narrowly trigonous axis,
disarticulating above the glumes. Spikelets with 1 perfect floret, the axis
extended past this as a short, slender bristle, occasionally with a tiny,
highly reduced floret. Glumes 1–2 mm long, lanceolate, 1‑nerved, sharply
pointed at the tip but unawned, the lower glume slightly shorter and somewhat
curved, the upper glume slightly longer and straight. Lemmas 1.7–2.8 mm long,
broadly boat‑shaped and keeled, 3‑nerved, the tip pointed, unawned,
hairy or roughened along the nerves. Paleas narrowly lanceolate, 2‑nerved.
Anthers 0.9–1.3 mm long, orangish yellow to yellow. Fruits 1.2–1.4 mm long,
elliptic in outline, somewhat flattened, yellow to yellowish brown. 2n=14,
18, 27, 30, 36, 40, 54. June–October.
Introduced, scattered, mostly south of the Missouri River
(presumed native of Africa, now a weed throughout the warmer parts of the
world). Pastures, gardens, roadsides, railroads, and open, disturbed areas.
Bermuda grass is an important turf species for golf courses
and commercial and residential lawns in the southern United States, where it
sometimes also is grown for forage. Missouri is toward the northern edge of the
region in which it is commonly cultivated. Occasional abnormal specimens have
some or all of the spikelets modified into leafy or stemlike structures.
Another member of the tribe Cynodonteae superficially
similar vegetatively to Bermuda grass is Zoysia Willd. Although the
inflorescence (a single, slender, cylindrical, spikelike raceme) and spikelets
(with the lower glume absent and the upper enlarged to enclose the floret) are
quite different from that of Cynodon, members of this genus spread
vegetatively by shallow, stolonlike rhizomes and have short, firm leaves.
Various cultivars of primarily Z. japonica Steud. are cultivated
commonly for lawns in Missouri, but Zoysia has not been documented as an
escape yet in the state. It has become established sporadically in the
southeastern states, and therefore eventually may be encountered in Missouri.