This section is from the book "Nature's Garden", by Neltje Blanchan. Also available from Amazon: Nature's Garden; An Aid To Knowledge Of Our Wild Flowers And Their Insect Visitors.
Flowers - White, about 1/2. in. across, clustered in a simple terminal raceme. Calyx of four sepals; corolla of 4 petals in form of a cross; 6 stamens; 1 compound pistil with a 2-lobed style. Stem: 6 to 18 in. high, erect, smooth, from a tuberous base. Leaves: Basal ones rounded, on long petioles; upper leaves oblong or lance-shaped, toothed or entire-edged, short peti-oled or seated on stem. Fruit: Very slender, erect pods about 1 in. long, tapering at each end, tipped with a slender style, the stigma prominent; 1 row of seeds in each cell, the pods rapidly following flowers up the stem and opening suddenly.
Flowering Season - April - June.
Distribution - Nova Scotia to Florida, west to Minnesota and Texas.
Pretty masses of this flower, that look like borders of garden candytuft planted beside some trickling brook, are visited and cross-fertilized by small bees, of the Andrena and Halictus clans chiefly. How well the butterflies understand scientific classification with instinct for their sure guide! The caterpillar of that exquisite little white butterfly with a dark yellow triangular spot across his wings, the fulcate orange-tip (Euchloe genutia), a first-cousin of the common small white cabbage butterfly, feeds on this plant and several of its kin, knowing better than if the books had told it so, that all belong to the same cross-bearing family. The watery, biting juice in the Cruciferae - the radishes, nasturtiums, cabbage, peppergrass, water-cress, mustards, and horseradish - by no means protects them from preying worms and caterpillars; but ants, the worst pilferers of nectar extant, let them alone. Authorities declare that the chloride of potassium and iodine these plants contain increase their food value to mankind.
The Purple Cress (C purpurea), formerly counted a mere variety of the preceding, has now been ranked as a distinct species. Its purplish-pink flowers, found about cold, springy places northward, appear two or three weeks earlier than those of the white spring cress.
The Meadow Bitter-cress (or Cross), Ladies' Smock, or Cuckoo-flower (C pratensis), an immigrant from Europe and Asia now naturalized here north of New Jersey from coast to coast, lifts its larger and more showy white or purplish-pink flowers, that stand well out from the stem on slender pedicels, in loose clusters above watery low-lying ground in April and May.
"Lady-smocks all silver white " now paint our meadows with delight, as they do Shakespeare's England; but ours have quite frequently a decided pink tinge. The light and graceful growth, and the pinnately divided foliage, give the plant a special charm. In olden times, when it was counted a valuable remedy in hysteria and epilepsy, Linnaeus gave it its generic name Cardamine from two Greek words signifying heart-strengthening.
More bees, flies, butterflies, and other insects visit the ladies' smock than perhaps any other crucifer found here, since it has showy flowers and so much nectar the long-persistent sepals require little pouches to hold it. No wonder this plant has triumphantly marched around the world, leaving its relatives that take less pains to woo and work insects far behind in the race. Owing to a partial revolution of the tall stamens away from the stigmas, a visitor in sipping nectar must brush off some pollen on his head or tongue, although in stormy weather, when the movement of the stamens is incomplete, self-pollination may occasionally occur, according to Muller.