POLYGONACEAE (BUCKWHEAT FAMILY) 99 
Stem rigidly upright, sometimes attaining four feet but more often 
six inches to two feet in height, much branched, slender, slightly 
ridged, and smooth. Leaves yellowish green, smooth, narrow 
lance-shaped, pointed at both ends, a quarter-inch to an inch long, 
with very short petioles conspicuously jointed to the collar-like 
stipules, which are funnel-form, thin, usually cut and torn. Flowers 
in axillary clusters, greenish with yellow margins; stamens three 
to six; sepals six, the three inner ones small, the outer ones 
larger, keeled and curving inward at the summit, persistent, their 
withered remains enfolding the smooth, shining, three-angled 
achenes when they mature and fall. 
Means of control 
Prevent reproduction by cutting or pulling when in first bloom. 
SWAMP SMARTWEED 
Polggonum Muhlengérgii, Wats. 
(Polggonum emérsum, Britton) 
Native. Perennial. Propagates by seeds and by rootstocks. 
Time of bloom: July to September. 
Seed-time: August to October. 
Range: Ontario to British Columbia, southward to Virginia, 
Louisiana, and Texas. 
Habitat: Muddy or dry soil; fields, low meadows, swamps. 
Although this weed seems to prefer moist soil, it will grow any- 
where, even on mountains, varying its form to fit its surroundings. 
When established in field or meadow its creeping, horizontal root- 
stocks make it difficult to suppress, as by ordinary cultivation they 
are likely to be broken and further distributed. 
Stems one to three feet long, decumbent or sometimes erect, 
usually simple, rough with short, appressed hairs, or sometimes 
smooth and slightly grooved, swollen at the joints. Leaves vari- 
able, those in wet places usually smooth, rather broad, and heart- 
shaped at base; in dry situations narrow, lance-shaped, pointed at 
base, and covered on both sides with appressed hairs ; loose sheath- 
ing stipules: nearly as long as the petioles. Flowers dark rose- 
