Bean family (Fabaceae)
Description: This perennial plant is ½–2' tall, branching occasionally. The hairy stems are sprawling or erect. The alternate compound leaves are trifoliate. The lower compound leaves have long hairy petioles, while the upper leaves have short petioles or they are sessile. The leaflets are up to 2" long and ¾" across. They are oval-ovate or slightly obovate; sometimes they are a little broader below the middle. Their margins are smooth and ciliate and their tips are blunt. Toward the middle of the upper surface of each leaflet, there is usually a chevron that is white or light green. The leaflets are sessile and lack petioles of their own. At the base of each compound leaf, there is a pair of ovate stipules up to ½" long. The upper stems terminate in flowerheads that are spheroid or ovoid. Usually there are 1-3 leaflets immediately beneath each flowerhead, as well as several green bracts with tips that abruptly taper to a slender tip. Each flowerhead is about 1" across and consists of numerous flowers. These flowers are sessile, tubular-shaped, and spread outward in different directions. Each flower has 5 narrow petals that are pink or purplish pink, becoming light pink or white toward the base of the flowerhead; a rare form of this species with white petals also exists. The upper petal is slightly longer than the lower petals. The light green calyx of each flower has 5 slender teeth and it is usually hairy.
The blooming period usually occurs from late spring to mid-summer and lasts about 1-2 months. However, a few plants may bloom later in the summer or fall. The flowers have a mild honey-like fragrance, while the foliage, when it exists in abundance, produces a distinctive clover-like aroma that is quite pleasant. Each flower is replaced by a small seedpod containing 1 or 2 heart-shaped seeds. The root system consists of a taproot and produces rhizomes. This plant can spread vegetatively or by reseeding itself.
Cultivation: The preference is full sun, mesic conditions, and a loam or clay-loam soil. This plant adds nitrogen to the soil by forming root nodules that accommodate rhizobial bacteria. Partial sun is tolerated.
Range & Habitat: The non-native Red Clover is a common plant that occurs in every county of Illinois (see Distribution Map). It was introduced from Eurasia as a fodder crop for farm animals and as a cover crop to improve agricultural soil. Habitats include fields, pastures, weedy meadows, vacant lots, grassy areas along roads, waste areas, and degraded prairie remnants. This plant occurs in native habitats occasionally, but it is only slightly to moderately aggressive. It is often found in grassy areas that are not subjected to regular mowing.
Faunal Associations: The nectar and pollen of the flowers attract many kinds of long-tongued bees, including bumblebees, Anthophorine bees, Mason bees, and large Leaf-Cutting bees (Megachilini tribe). Butterflies, skippers, and day-flying Sphinx moths also visit the flowers for nectar. Typical visitors among the butterflies include Swallowtails, Monarchs, Painted Ladies, Whites, and Sulfurs. The caterpillars of several butterflies feed on the foliage, including Everes comyntas (Eastern Tailed-Blue), Colias eurytheme (Orange Sulfur), Colias philodice (Clouded Sulfur), and Colias cesonia (Dog-Faced Sulfur). The caterpillars of many moth species feed on the foliage of this and other Trifolium spp. as well (see Moth Table). Both the seedheads and foliage are eaten occasionally by upland gamebirds, including the Ruffed Grouse, Greater Prairie Chicken, Wild Turkey, and Ring-Necked Pheasant. Similarly, many small mammals eat the seedheads and/or foliage, including the Cottontail Rabbit, Groundhog, Thirteen-Lined Ground Squirrel, and Meadow Vole. Among the hoofed browsers, the foliage of Red Clover is readily eaten by deer, horses, cattle, and sheep. The value of Red Clover to wildlife and domestic animals is high.
Photographic Location: A weedy meadow at Judge Webber Park in Urbana, Illinois.
Comments: Among the various Trifolium spp. (Clovers), Red Clover is fairly easy to identify because of its large pink flowerheads and the white chevrons on its leaflets. It is unusual among the clovers in having sessile leaflets at the base of the flowerheads. There is some variability in the hairiness of the foliage and the color of the flowers. The common name is somewhat misleading because the flowers are never a true red. On rare occasions, a compound leaf will produce 4 or more leaflets.