Description: This is a biennial or
short-lived perennial plant up to 5' tall. It branches frequently at the leaf
nodes and has a rather bushy appearance when mature. The stems are dark red and
have conspicuous white hairs, particularly in the upper half of the plant. The
alternate leaves are up to 4" long and 2" across. They are broadly ovate or
lanceolate, slightly to coarsely serrated, and have a rough texture. Some of
the lower leaves are divided into three lobes. At the end of each upper stem, a
single composite flower develops with a daisy-like appearance. It is about
1½-2" across, with 6-12 yellow ray florets surrounding a brown flattened
cone of numerous disk florets. The compound flowers have little or no scent.
The blooming period occurs for a month or two during mid-summer to late summer.
There are usually a half-dozen or more compound flowers in bloom at any given
time, creating a showy effect. The achenes are 4-angled and have no tufts of
hair. The root system is shallow and fibrous.
Cultivation: The preference is full to partial sun,
and moist to mesic conditions. A rich loam produces the best growth, although a
soil with some gravel or clay is tolerated. This plant has limited drought
tolerance, and may drop some of its lower leaves should this occur. After the
blooming season is over, Brown-Eyed Susan can appear untidy.
Range & Habitat: This is a common plant in
Illinois, except for some counties in the south and northwest (see
Distribution
Map). Brown-Eyed Susan occurs occasionally in moist to mesic black soil
prairies, brushy thickets, and openings or lightly shaded areas of floodplain
forests. It also occurs in some wetland areas, such as fens and lakeside
borders, and in some developed areas, such as partially shaded vacant lots and
abandoned fields. This plant favors disturbed areas in these various
ecosystems.
Faunal
Associations: This plant is often self-pollinated, but nonetheless
attracts numerous insect visitors to the flowers. These include both
long-tongued and short-tongued bees, including bumblebees, Little Carpenter
bees, Miner bees, Green Metallic bees, Panurgine bees, and Andrenine bees.
Among the latter, Andrena aliciae and Andrena rudbeckiae tend to
restrict their visits to various species of coneflowers. Various flies are
common visitors, including Syrphid flies, Bee flies, and Tachinid flies. Some
butterflies, wasps, and beetles visit the flowers occasionally, including
Chlosyne nycteis (Silvery Checkerspot), Phyciodes tharos (Pearl
Crescent), and Chauliognathus pennsylvanicus (Goldenrod Soldier Beetle).
Bees suck nectar and collect pollen, while other insect visitors seek nectar
only.
Photographic Location: The
photographs were taken at of plants growing in a wildflower garden at Crystal
Lake Park, Urbana, Illinois.
Comments: This coneflower can be distinguished from
others by the smaller size of the flowers, which also have fewer ray florets.
It is often observed in the eastern range of the tallgrass prairie, but tends
to retreat to wetland or woodland areas further to the west where rainfall
amounts are lower and summer temperatures are more extreme.