11. Chenopodium missouriense Aellen
C. album L. var. missouriense Bassett
& Crompton
Pl. 355 f, g;
Map 1531
Plants annual,
without an odor. Stems 20–150 cm long, erect or ascending, usually few- to
several-branched above the base and below the inflorescence, glabrous or more
commonly sparsely to moderately white-mealy, sometimes reddish-tinged or
reddish purple–striped, almost always reddish purple at each node (on the side
to which the leaf is attached). Leaves mostly long-petiolate. Leaf blades 1–6
cm long, mostly 1–3 times as long as wide (1–4 cm wide), usually 1.2–1.5 times
in the largest (lowermost) leaves, ovate-rhombic or ovate-triangular, the
uppermost usually linear to narrowly lanceolate, angled or tapered to a rounded
or more commonly bluntly to sharply pointed tip, the middle lobe not appearing
unusually elongate, broadly angled at the base, green or reddish-tinged, thin
and herbaceous to thickened, somewhat leathery, and slightly succulent in
texture, the margins entire to wavy or irregularly and often relatively
coarsely several-toothed (the basal pair of teeth sometimes larger than the
others, sometimes appearing shallowly lobed), the upper surface glabrous or
sparsely to moderately mealy at maturity, not shiny, the undersurface sparsely
to moderately white-mealy. Venation noticeably branched, with 1 or 3 main
veins. Inflorescences axillary and terminal, consisting of short spikes with
often well-separated small clusters of flowers, the terminal ones usually
grouped into small to relatively large panicles. Flowers all maturing at more
or less the same time. Calyx 5-lobed nearly to the base, usually covering the
entire fruit except sometimes for a minute area surrounding the style,
occasionally somewhat spreading in a few flowers of a given inflorescence, the
lobes 0.7–1.0 mm long, ovate to triangular-ovate, bluntly pointed at the tip,
usually with a sometimes poorly developed narrow keel or raised area along the
midvein dorsally, sparsely to moderately white-mealy. Stamens 5. Stigmas 2.
Fruits 0.9–1.1(–1.2) mm wide, depressed-ovoid, the seeds positioned
horizontally, the wall thin, membranous, and somewhat translucent, smooth or
finely roughened, not appearing honeycombed, sometimes difficult to separate
from the seed. Seeds black, shiny, smooth or nearly so, rounded to very bluntly
angled along the rim. 2n=54. September–October.
Scattered nearly
throughout the state (eastern U.S. west to North Dakota and Texas; introduced
farther west to California and Alaska; Canada). Banks of streams, rivers,
spring branches, and sloughs, less commonly in bottomland forests and mesic
upland forests; also crop fields, fallow fields, roadsides, railroads, and
open, disturbed areas.
The
inflorescences of C. missouriense tend to be more open and have more
spreading, relatively slender branches than those of C. album.
Relatively synchronous autumnal flowering and small fruits also are
characteristic of C. missouriense. The reddish patches at the stem nodes
occasionally are poorly developed.