_Polygonum pennsylvanicum_
_Flowers_--Very small, pink, collected in terminal, dense, narrow obtuse
spikes, 1 to 2 in. long. Calyx pink or greenish, 5-parted, like petals;
no corolla; stamens 8 _or_ less; style 2-parted. _Stem:_ 1 to 3 ft.
high, simple or branched; often partly red, the joints swollen and
sheathed; the branches above, and peduncles glandular. _Leaves:_ Oblong,
lance-shaped, entire edged, 2 to 11 in. long, with stout midrib, sharply
tapering at tip, rounded into short petioles below.
_Preferred Habitat_--Waste places, roadsides, moist soil.
_Flowering Season_--July-October.
_Distribution_--Nova Scotia to the Gulf of Mexico; westward to Texas and
Minnesota.
Everywhere we meet this commonest of plants or some of its similar kin,
the erect pink spikes brightening roadsides, rubbish heaps, fields, and
waste places, from midsummer to frost. The little flowers, which open
without method anywhere on the spike they choose, attract many insects,
the smaller bees (_Andrena_) conspicuous among the host. As the
spreading divisions of the perianth make nectar-stealing all too easy
for ants and other crawlers that would not come in contact with anthers
and stigma where they enter a flower near its base, most buckwheat
plants whose blossoms secrete sweets protect themselves from theft by
coating the upper stems with glandular hairs that effectually discourage
the pilferers. Shortly after fertilization, the little rounded,
flat-sided fruit begins to form inside the persistent pink calyx. At any
time the spike-like racemes contain more bright pink buds and shining
seeds than flowers. Familiarity alone breeds contempt for this plant,
that certainly possesses much beauty. The troublesome and wide-ranging
weed called lady’s thumb is a near relative.