American bellflower (Campanulastrum americanum)
Campanula americana L.
Campanula americana var. illinoensis (Fresen.) Farw.
CONFIRMATION STATUS: Pending confirmation.
TAXONOMY: The currently accepted scientific name of American bell-
flower is Campanulastrum americanum (L.) Small. The older scientific
name is Campanula americana, but it has been reassigned to its own gen-
us (Campanulastrum) because of the unique structure of the flowers. The
other members of the Bellflower Family, whether native or introduced,
have bell-shaped flowers, while the flowers of the American bellflower
have a more open design with widely spreading lobes. Consequently, this
species is easy to identify.
NATIVE STATUS: Native, United States and Canada.
GENERAL BOTANICAL CHARACTERISTICS:
Habit: This native plant is an annual or biennial from 2-6' tall. Usually, it
is unbranched, although sometimes a few side stems will develop from the
lower central stem. The central stem is more or less hairy.
Leaves: The alternate leaves are up to 6" long and 2" across, tapering to
slender petioles. They are lanceolate to ovate, with serrated margins and a
rough upper surface.
Flowers: The central stem terminates in a spike of flowers about ½2' long.
From the axils of the upper leaves, secondary spikes of flowers may devel-
op, but these are much shorter (about 16" in length). Each flower is about
1" across, and varies in color from light to dark violet-blue. The corolla has
5 spreading lobes that are divided nearly to the base; they have a satiny
appearance under bright light, and tend to have margins that twist and curl.
In the center of the flower is the top of a 5-angled ovary, from which a light
violet style is strongly exerted. This style bends downward from the flower,
but curls upward near its tip; the small stigma is white and divided into 3
lobes. The flower is often white toward the center, rather than blue- violet.
The green tubular calyx is strongly ridged and has 5 long narrow teeth that
curl backward when the flower opens.
Fruit/Seeds: The seed capsule is 5-angled and rather flat-topped.
Roots: The root system consists of a taproot.
REGENERATION PROCESS: American bellflower propogates itself
HABITAT TYPES: Habitats include moist to slightly dry deciduous
woodlands, woodland borders, and thickets. It is often found along
woodland paths, and appears to prefer slightly disturbed areas.
SITE CHARACTERICS: American bellflower perfers light shade to
partial sun, moist to mesic conditions, and a rich loamy soil. During a
drought, this plant often drops its lower leaves. Depending on moisture
conditions and the fertility of the soil, the size of this plant can be highly
SEASONAL DEVELOPMENT: The blooming period occurs from mid-
summer to early fall, and lasts about 1½ months.
GENERAL DISTRIBUTION: American bellflower is primarily a spec-
ies of the eastern United States, ranging from Florida to the mid-Atlantic
states, but not New England, and extending west through the Ohio Valley
region to the beginning of the Great Plains (Oklahoma north to South Da-
kota). It is not naturally found in the western Great Plains states nor in the
far western states. It has been reported as occurring in Ontario, but not the
other Canadian provinces.
SKY MEADOWS DISTRIBUTION: To be determined.
IMPORTANCE AND USES: Long-tongued bees are the primary pol-
linators of the flowers, including bumblebees and large leaf-cutting bees
(Megachilidae). Among the latter, is the oligolectic bee Megachile
campanulae campanulae. Other visitors of the flowers include halictid
bees, butterflies, and skippers. These insects seek nectar, and some of
the bees collect pollen from the anthers. Syrphid flies may feed on the
pollen, but they are not effective pollinators. Deer occasionally eat the
flowers and foliage.
Crooked Run Valley