Madder family (Rubiaceae)
Description: This native perennial wildflower is ¾–2' tall with erect to ascending stems. These stems are sometimes branched at the base, otherwise they are unbranched (except when axillary inflorescences are present). The stems are light green, 4-angled, and glabrous to sparsely hairy. At intervals along these stems, there are whorls of 4 leaves. The leaves are up to 2½" long and 1" across, lanceolate-ovate to ovate, medium green, sessile, and sparsely pubescent on both the lower and upper sides. Their margins are smooth and ciliate. Each leaf has 3 prominent parallel veins. Usually, the leaves toward the middle of each stem are largest. Each major stem terminates in a dichotomously forked inflorescence that produces only a few flowers; sometimes smaller inflorescences develop from the axils of the upper leaves. Like the stems, the branches of each inflorescence are 4-angled, light green, and glabrous to sparsely hairy. At each fork of the inflorescence, there are 0-4 small bracts that are linear or linear-lanceolate in shape.
The flowers occur individually along these branches and they are usually sessile (or nearly so). Each flower is about 1/8" across, consisting of a corolla with 4 lobes, a double-ovoid ovary, 4 stamens, and a pair of styles. The corolla is usually greenish white or greenish yellow; less often, it is purple. The immature ovary is green, bristly, and 2-celled. The blooming period usually occurs during the early summer and lasts about a month. At maturity, each ovary becomes a dry fruit that is black or dark brown, globoid in shape, and covered with hooked bristles. One cell of this fruit produces a single nutlet, while the other cell becomes a small fleshy elaiosome (food appendage). The root system is fibrous and rhizomatous. This wildflower spreads by reseeding itself or vegetatively through its rhizomes.
Cultivation: The preference is dappled sunlight to medium shade, mesic to dry conditions, and a loamy or rocky soil with some decaying organic matter (e.g., fallen leaves). The foliage usually remains in good condition throughout the summer.
Range & Habitat: Wild Licorice is occasional to locally common throughout Illinois (see Distribution Map). Habitats include mesic to dry deciduous woodlands, bluffs, woodland borders, areas along woodland paths, thickets, and limestone glades.
Faunal Associations: The flowers are visited sparingly by small bees and miscellaneous flies; these insects usually seek nectar. The caterpillars of several moths feed on Galium spp. (Bedstraws), including Lobocleta ossularia (Drab Brown Wave), Pleuroprucha insularia (Common Tan Wave), Scopula limboundata (Large Lace Border), Epirrhoe alternata (White-Banded Toothed Carpet), and Hyles gallii (Galium Sphinx). Bedstraws are summer hosts of Myzus cerasi (Black Cherry Aphid); another aphid, Aphis gossypii (Cotton Aphid), has been found on the leaves of Wild Licorice. Among vertebrate animals, the Eastern Box Turtle occasionally eats the foliage of bedstraws in woodlands; White-Tailed Deer also eat the foliage of these plants to a limited extent. The hooked bristles of the fruits can cling to the fur of mammals and the clothing of humans; this distributes the seeds into new areas. Because each fruit contains an elaiosome that is attractive to ants, these insects also help to distribute the seeds.
Photographic Location: A deciduous woodland at Pine Hills Nature Preserve in west-central Indiana.
Comments: While the flowers are not very showy, the foliage is reasonably attractive. Wild Licorice has larger leaves than most Galium spp. (Bedstraws). In addition to this characteristic, it can be distinguished from other bedstraws by its whorls of 4 leaves, pubescent leaves, bristly fruit, and/or flowers that are sessile along the branches of each inflorescence. A very similar species, Galium lanceolatum (Lance-Leaved Wild Licorice), has hairless leaves that are more narrow toward their tips, and its flowers are usually purple. Both of these species prefer shaded habitats that are rather dry.