CROWFOOT FAMILY - Ranunculaceae: Tall Meadow-rue
Thalictrum polygamum (T. Cornuti)
Flowers--Greenish white, the calyx of 4 or 5 sepals, falling early; no petals; numerous white, thread-like, green-tipped stamens, spreading in feathery tufts, borne in large, loose, compound terminal clusters 1 ft. long or more. Stem: Stout, erect, 3 to 11 ft. high, leafy, branching above. Leaves: Arranged in threes, compounded of various shaped leaflets, the lobes pointed or rounded, dark above, paler below.
Preferred Habitat--Open sunny swamps, beside sluggish water, low meadows.
Distribution--Quebec to Florida, westward to Ohio.
Masses of these soft, feathery flowers, towering above the ranker
growth of midsummer, possess an unseasonable, ethereal, chaste,
spring-like beauty. On some plants the flowers are fleecy white and
exquisite; others, again, are dull and coarser. Why is this? Because
these are what botanists term polygamous flowers, i.e., some of
them are perfect, containing both stamens and pistils; some are male
only; others, again, are female. Naturally an insect, like ourselves,
is first attracted to the more beautiful male blossoms, the pollen
bearers, and of course it transfers the vitalizing dust to the dull
pistillate flowers visited later. But the meadow-rue, which produces a
super-abundance of very light, dry pollen, easily blown by the wind,
is often fertilized through that agent also, just as grasses,
plantains, sedges, birches, oaks, pines, and all cone-bearing trees
are. As might be expected, a plant which has not yet ascended the
evolutionary scale high enough to economize its pollen by making
insects carry it invariably overtops surrounding vegetation to take
advantage of every breeze that blows.
The Early Meadow-rue (T. dioicum), found blooming in open, rocky woods during April and May, from Alabama northward to Labrador, and westward to Missouri, grows only one or two feet high, and, like its tall sister, bears fleecy, greenish-white flowers, the staminate and the pistillate ones on different plants.