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.
Resembling the white sweet clover, except in color. (See p. 208.)
Flowers - Yellow, scale-like, overlapping in a densely many-flowered oblong head about 1/2 in. long, becoming brown with age. Stem: Ascending, branched, 6 to 18 in. high. Leaves: 3-foliate, very finely toothed.
Rabbit-Foot Clover (Trifolium arvense)
Preferred Habitat - Waste places, fields, roadsides.
Flowering Season - May - September.
Distribution - Virginia to Iowa, and far northward.
What did the sulphur butterflies provide as food for their caterpillar babies before the commonest ciovers came over from the Old World to possess the soil? Wherever a trifolium grows, there one is sure to see
" Sallow-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.