Description: This native perennial vine is up to 10' long and somewhat woody. The young stems are angular, terete, slightly pubescent, and green or red. Older stems become hairless, brown, and woody, otherwise they resemble the young stems. Pairs of opposite leaves occur at intervals along the vine. These leaves are simple or compound; if the latter, they are odd pinnate. Simple leaves and leaflets are up to 3" long and 2" across. They are ovate or cordate-ovate, smooth along the margins, and largely hairless; sometimes 1 or 2 lateral lobes are present. The major veins of each leaf are parallel, while the secondary veins criss-cross between them. These veins are often elevated and conspicuous on the lower surface. Each simple leaf or leaflet has a slender petiole that is slightly pubescent.
From the axils of the upper leaves, there
often develops a single flower on a long pedicel; this flower nods downward.
Each flower is about ¾" long and bell-shaped. It consists of 4 thick
leathery sepals and no petals; within the flower, there are several stamens and
styles. The sepals are slightly pubescent and light purple, except near their
recurved tips, where they are light green or white. The blooming period occurs
during the summer (usually mid-summer) and lasts about a month. Each flower is
replaced by a whorl of flattened achenes with long beaks that are persistent
styles. The tips of these styles are slightly hairy, becoming hairless with
age. The achenes are light green or burgundy and have a spidery appearance;
they become brown or black with age. They are blown about by the wind to a
limited extent.
Cultivation: The
preference is partial sun, moist to mesic conditions, and a soil that is loamy
or rocky. Full sun and drier conditions are also tolerated, but the leaves have
a tendency to turn yellow during hot dry weather.
Range & Habitat: Pitcher's Leather Flower is
occasional to common throughout Illinois, except for the upper two tiers of
counties in NE and north-central areas of the state, where it is absent (see
Distribution
Map). This is one of the more common Clematis spp. in Illinois.
Habitats include open woodlands, rocky
bluffs, woodland borders, areas along
woodland paths, powerline clearances through wooded areas, thickets, and fence
rows. This species tolerates human-caused disturbance to some extent; it
doesn't spread to new areas readily.
Faunal
Associations: Bumblebees pollinate the flowers, where they suck
nectar and collect pollen. The caterpillars of the moths Thysis maculata
(Spotted Thyris) and Thysis sepulchralis (Mournful Thyris) feed on the
foliage of Clematis spp. The foliage is probably poisonous to mammalian
herbivores.
Photographic Location:
The upper photograph was taken at a powerline clearance in Busey Woods of
Urbana, Illinois, while the lower photograph was taken at a roadside fence row
in rural Champaign County, Illinois.
Comments: The Clematis spp. that are Leather
Flowers have similar-appearing bell-shaped flowers that nod downward. Other
Clematis spp., such as Clematis virginiana (Virgin's Bower), have
showier flowers with spreading white sepals and conspicuous stamens and styles.
However, both groups of Clematis spp. have whorled flattened achenes
with long beaks that are persistent styles. Pitcher's Leather Flower has a
similar appearance to Clematis viorna (Leather Flower). However, the
persistent styles of Pitcher's Leather Flower are slightly hairy or glabrous
toward their tips, while the persistent styles of Leather Flower have abundant
plumose hairs. Sometimes the leaf undersides of Pitcher's Leather Flower have
conspicuous elevated veins, while the leaf undersides of Leather Flower are
more smooth. However, this distinction is not always reliable. Leather Flower
is an uncommon species that occurs in only a few counties in southern Illinois.
It is more common outside of the state in areas that are further to the east
and south.