Aster family (Asteraceae)
Description: This perennial wildflower is 1-5' tall and either unbranched or sparingly so. The central stem is erect, terete, densely hairy or pubescent, and light green to brownish red. The alternate leaves are up to 4" long and 1½" across; they are ovate, narrowly ovate, ovate-lanceolate, or ovate-oblanceolate in shape with crenate-serrate margins. The upper surfaces of the leaves are deeply indented by pinnate veins; this characteristic provides them with a somewhat wrinkled appearance. Additionally, the upper surfaces of the leaves are slightly pubescent to hairless, medium to dark green, and usually dull-colored. The central stem terminates in a panicle of yellow flowerheads of variable shape and size. Small plants often have narrow panicles that resemble racemes, while large plants often have broad panicles with spreading-recurved branches. The upper stems of some large plants may produce panicles that are smaller than that of the central stem.
Each yellow flowerhead spans about 1/8" (3 mm.) across, consisting of 4-8 ray florets and a similar number of tubular disk florets. The base of each flowerhead consists of overlapping scale-like bracts that are yellowish-green. The branches of larger panicles often have small leafy bracts. The blooming period can occur from mid-summer into the fall and lasts about 1-2 months. Each fertile floret is replaced by a small bullet-shaped achene with a short tuft of hairs at its apex. The root system is fibrous and rhizomatous. Vegetative colonies of plants are often formed by the spreading rhizomes.
Cultivation: The preference is full sun to light shade, moist conditions, and soil that is sandy, loamy, or gravelly with a slightly acid pH.
Range & Habitat: The native Wrinkled-Leaved Goldenrod occurs primarily in the southwest corner of Illinois, where it is uncommon. Elsewhere in the state, it is rare or absent (see Distribution Map). Illinois lies at the NW range limit of this species. Habitats include low open woodlands, thickets, sandy swamps, wet sandy prairies, sandy banks of marshes, acid gravelly seeps, sand dunes, and rocky bluffs or cliffs. Usually, this goldenrod is found in moist areas that are sandy or where sandstone is close to the ground surface. Sometimes it is found in gardens, although some cultivars of this species bear little resemblance to the native plants.
Faunal Associations: The nectar and pollen of the flowers attract a wide variety of insects, including small bees, wasps, flies, small butterflies, skippers, and beetles. The caterpillars of many moth species feed on various parts of goldenrods (see Moth Table), while several leaf beetles (Chrysomelidae) feed primarily on the foliage (see Leaf Beetle Table). Other insects that feed on goldenrods include various plant bugs, stink bugs, lace bugs, treehoppers, and leafhoppers; the Bug Table lists some of these species. Insectivorous birds benefit indirectly from goldenrods because of the numerous insects that they attract. Other birds feed directly on goldenrods to a minor extent, including the Indigo Bunting (seeds), Eastern Goldfinch (seeds), Swamp Sparrow (seeds), Ruffed Grouse (leaves), and Greater Prairie Chicken (leaves). White-Tailed Deer and Cottontail Rabbits feed on young foliage to a limited extent, while Meadow Voles eat both the seeds and foliage.
Photographic Location: A sandy bank along a marsh at Jasper-Pulaski Fish and Wildlife Area in northwestern Indiana. The photographed plant is a dwarf (about 1½' tall) that may have been mowed earlier in the year.
Comments: Across it range in the eastern United States, this goldenrod is somewhat variable in appearance. Nonetheless, Wrinkle-Leaved Goldenrod can be distinguished from other goldenrods as follows: 1) the central stem is quite hairy or pubescent, 2) the upper surfaces of the leaves have a wrinkled appearance because of the indentations of their pinnate veins, and 3) individual leaves lack 3 prominent veins that run parallel to each other. This latter characteristic is typical of Solidago canadensis (Canada Goldenrod), Solidago gigantea (Giant Goldenrod), and similar goldenrods. Two other species, Solidago ulmifolia (Elm-Leaved Goldenrod) and Solidago patula (Swamp Goldenrod), have stems that are glabrous or only slightly hairy and their leaves tend to be more thin in texture and shiny than those of Wrinkle-Leaved Goldenrod. Other common names of Solidago rugosa include 'Rough-Stemmed Goldenrod,' 'Rough Goldenrod,' and 'Rough-Leaved Goldenrod.'