(Oxalis violacea) Wood-sorrel family
Flowers - Pinkish purple, lavender, or pale magenta; less than 1
in. long; borne on slender stems in umbels or forking clusters,
each containing from 3 to 12 flowers. Calyx of 5 obtuse sepals; 5
petals; 10 (5 longer,
5 shorter) stamens; 5 styles persistent
above 5-celled ovary. Stem: From brownish, scaly bulb 4 to 9 in.
high. Leaves: About 1 in. wide, compounded of 3 rounded,
clover-like leaflets with prominent midrib, borne at end of
slender petioles, springing from root.
Preferred Habitat - Rocky and sandy woods.
Flowering Season - May-June.
Distribution - Northern United States to Rocky Mountains, south
to Florida and New Mexico; more abundant southward.
Beauty of Leaf and blossom is not the only attraction possessed
by this charming little plant. As a family the wood-sorrels have
great interest for botanists since Darwin devoted such exhaustive
study to their power of movement, and many other scientists have
described the several forms assumed by perfect flowers of the
same species to secure cross-fertilization. Some members of the
clan also bear blind flowers, which have been described in the
account of the white wood-sorrel given above. Even the
rudimentary leaves of the seedlings "go to sleep" at evening, and
during the day are in constant movement up and down. The stems,
too, are restless; and as for the mature leaves, every child
knows how they droop their three leaflets back to back against
the stem at evening, elevating them to the perfect horizontal
again by day. Extreme sensitiveness to light has been thought to
be the true explanation of so much activity, and yet this is not
a satisfactory theory in many cases. It is certain that drooping
leaves suffer far less from frost than those whose upper surfaces
are flatly exposed to the zenith. This view that the sleep of
leaves saves them from being chilled at night by radiation is
Darwin's own, supported by innumerable experiments; and probably
it would have been advanced by Linnaeus, too, since so many of
his observations in "Somnus Plantarum" verify the theory, had the
principle of radiation been discovered in his day.
The violet wood-sorrel produces two sorts of perfect flowers
reciprocally adapted to each other, but on different plants in
the same neighborhood. The two are essentially alike, except in
arrangement of stamens and pistil; one flower having high anthers
and low stigmas, the other having lower anthers and higher
stigmas; and as the high stigmas are fertile only when pollenized
with grains from a flower having high anthers, it is evident
insect aid to transfer pollen is indispensable here. Small bees,
which visit these blossoms abundantly, are their benefactors;
although there is nothing to prevent pollen from falling on the
stigmas of the short-styled form. Hildebrand proved that
productiveness is greatest, or exists only, after legitimate
fertilization. To accomplish cross-pollination, many plants bear
flowers of opposite sexes on different individuals; but the
violet wood-sorrel's plan, utilized by the bluet and
partridge-vine also, has the advantage in that both kinds of its
flowers are fruitful.
COMMON, FIELD, or PURPLE MILKWORT; PURPLE POLYGALA
(Polygala viridescens; P. sanguinca of Gray) Milkwort family
Flowers - Numerous, very small, variable; bright magenta, pink,
or almost red, or pale to whiteness, or greenish, clustered in a
globular clover-like head, gradually lengthening to a cylindric
spike. Stem: 6 to 15 in. high, smooth, branched above, leafy.
Leaves: Alternate, narrowly oblong, entire.
Preferred Habitat - Fields and meadows, moist or sandy.
Flowering Season - June-September.
Distribution - Southern Canada to North Carolina, westward to the
When these bright clover-like heads and the inconspicuous
greenish ones grow together, the difference between them is so
striking it is no wonder Linnaeus thought they were borne by two
distinct species, sanguinea and viridescens, whereas they are now
known to be merely two forms of the same flower. At first glance
one might mistake the irregular little blossom for a member of
the pea family; two of the five very unequal sepals - not petals
- are colored wings. These bright-hued calyx-parts overlap around
the flower-head like tiles on a roof. Within each pair of wings
are three petals united into a tube, split on the back, to expose
the vital organs to contact with the bee, the milkwort's best
Plants of this genus were named polygala, the Greek for much
milk, not because they have milky juice - for it is bitter and
clear - but because feeding on them is supposed to increase the
flow of cattle's milk.
In sandy swamps, especially near the coast from Maine to the
Gulf, and westward to the Mississippi, grows the MARSH or
CROSS-LEAVED MILKWORT (P. cruciata). Most of its leaves,
especially the lower ones, are in whorls of four, and from July
to September its dense, bright purple-pink, white, or greenish
flower-heads, the wings awn-pointed, are seated on the ends of
the square branching stem of this low, mossy little plant.
FRINGED MILKWORT or POLYGALA; FLOWERING WINTERGREEN; GAY WINGS
(Polygala paucifolia) Milkwort family
Flowers - Purplish rose, rarely white, showy, over 1/2 in. long,
from 1 to 4 on short, slender peduncles from among upper leaves.
Calyx of 5 unequal sepals, of which 2 are wing-like and highly
colored like petals. Corolla irregular, its crest finely fringed;
6 stamens; pistil. Also pale, pouch-like, cleistogamous flowers
underground. Stem: Prostrate, 6 to 15 in. long, slender, from
creeping rootstock, sending up flowering shoots 4 to 7 in. high.
Leaves: Clustered at summit, oblong, or pointed egg-shaped, 1 1/2
in. long or less; those on lower part of shoots scale-like.
Preferred habitat - Moist, rich woods, pine lands, light soil.
Flowering Season - May-July.
Distribution - Northern Canada, southward and westward to Georgia
Gay companies of these charming, bright little blossoms hidden
away in the woods suggest a swarm of tiny mauve butterflies that
have settled among the wintergreen leaves. Unlike the common
milkwort and many of its kin that grow in clover-like heads, each
one of the gay wings has beauty enough to stand alone, Its oddity
of structure, its lovely color and enticing fringe, lead one to
suspect it of extraordinary desire to woo some insect that will
carry its pollen from blossom to blossom and so enable the plant
to produce cross-fertilized seed to counteract the evil
tendencies resulting from the more prolific self-fertilized
cleistogamous flowers buried in the ground below. It has been
said that the fringed polygala keeps "one flower for beauty and
one for use"; "one playful flower for the world, another for
serious use and posterity"; but surely the showy flowers, the
"giddy sisters," borne by all cleistogamous species to save them
from degenerating through close inbreeding, are no idle,
irresponsible beauties. Let us watch a bumblebee as she alights
on the convenient fringe which edges the lower petal of this
milkwort. Now the weight of her body so depresses the keel, or
tubular petals, wherein the stamens and pistil lie protected from
the rain and useless insects, that as soon as it is pressed
downward a spoon-tipped pistil pushes out the pollen through the
slit on the top on the bee's abdomen. The stigmatic surface of
the pistil is on the opposite side of the spoon, nearest the base
of the flower, to guard against self-pollination. After the
pollen has been removed, a bumblebee, already dusted from other
blossoms, must leave some on the stigma as she sucks the nectar.
Indeed, every feature possessed by this pretty flower has been
developed for the most serious purpose of life - the salvation of
Only locally common throughout a wide area, embracing the eastern
half of the United States and Canada, is the RACEMED MILKWORT (P.
polygama), whose small, purple-pink, but showy flowers, clustered
along the upper part of numerous leafy stems, are found in dry
soil during June and July. Like the fringed milkwort, this one
bears many cleistogamous, or blind flowers, on underground
branches, flowers that always set an abundance of fertile
self-planted seed in case of failure to form any on the part of
their showy sisters, which are utterly dependent upon the bee's
ministrations. During prolonged stormy weather few insects are
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