What did the sulphur butterflies provide as food for their caterpillar babies before the commonest clovers came over from the Old World to possess the soil? Wherever a trifolium grows, there one is sure to see
"gallow-yellow butterflies,
Like blooms of lorn primroses blowing loose,
when autumn winds arise."
The BLACKSEED HOP CLOVER, BLACK or HOP MEDIC (Medicago lupulina), with even smaller, bright yellow oblong heads which turn black when ripe, lies on the ground, its branches spreading where they leave the root. A native of Europe and Asia, it is now distributed as a common weed throughout our area, for there is scarcely a month in the year when it does not bloom and set seed. It is still another of the many plants known as the shamrock.
YELLOW WOOD-SORREL; LADY'S SORREL
(Oxalis stricta) Wood-sorrel family
Flowers - Golden, fragrant, in long peduncled, small, terminal groups. Calyx of 5 sepals; corolla of 5 petals, usually reddish at base; stamens, 10; 1 pistil with 5 styles; followed by slender pods. Stem: Pale, erect, 3 to 12 in. high, the sap sour. Leaves: Palmately compound, of 3 heart-shaped, clover-like leaflets on long petioles. Preferred Habitat - Open woodlands, waste or cultivated soil, roadsides. Flowering Season - April-October. Distribution - Nova Scotia and Dakota westward to the Gulf of Mexico.
An extremely common little weed, whose peculiarly sensitive leaves children delight to set in motion by rubbing, or to chew for the sour juice. Concerning the night "sleep" of wood-sorrel leaves and the two kinds of flowers these plants bear, see the white and violet wood-sorrels.
WILD or SLENDER YELLOW FLAX
(Linum Virginianum) Flax family
Flowers - Yellow, about 1/3 in. across, each from a leaf axil,
scattered along the slender branches. Sepals, 5; 5 petals, 5
stamens. Stem: 1 to 2 ft. high, branching, leafy. Leaves.
Alternate, seated on the stem; small, oblong, or lance-shaped, 1
nerved.
Preferred Habitat - Dry woodlands and borders; shady places.
Flowering Season - June-August.
Distribution - New England to Georgia.
Certainly in the Atlantic States this is the commonest of its slender, dainty tribe; but in bogs and swamps farther southward and westward to Texas the RIDGED YELLOW FLAX (L. striatum), with leaves arranged opposite each other up to the branches and an angled stem so sticky it "adheres to paper in which it is dried," takes its place.
"Blue were her eyes as the fairy flax,"