This herbaceous perennial plant is ½–2' tall and unbranched. The
central stem is light green, glabrous to pubescent, and slender.
Several alternate leaves occur along this stem; the stem has a tendency
to zigzag between pairs of succeeding leaves. The leaf blades are 2–5"
long and ½–2" across; they are narrowly cordate, ovate-sagittate, or
narrowly hastate with a pair of rounded basal lobes. The leaves are
where the petioles join the blades, and their tips are narrowly acute
to acute. Two varieties of this plant have been described: the typical
variety (var. serpentaria
has leaves usually exceeding ¾" in wide that
are cordate or ovate-sagittate in shape, while a narrow-leaved variety (var. hastata
leaves less than ¾" across that are narrowly hastate in shape.
Both the upper and lower surfaces of the leaf blades are medium green
and glabrous. The slender petioles are light green and ¼–1¼" long. One
or more solitary flowers are produced from the tips of lateral stems
that are found at the base of the plant; these flowers are held
slightly above the ground surface, lie directly on the ground surface,
or they are buried by fallen leaves. The alternate leaves of these
lateral stems have been reduced to bracts that are less than ¼" in
length. The flowers are ½–¾" in length; they are shaped somewhat like
an old-fashioned tobacco pipe. Each flower has a petaloid calyx that is
tubular and curved, 6 stamens, and an inferior ovary with a single
style and 3-lobed stigma. The petaloid calyx is somewhat constricted at
the throat, while its narrow outer opening is surrounded by 3 blunt
lobes that are joined together and spreading. The outer surface of the
petaloid calyx varies in color from pale greenish purple to deep
reddish brown (maroon) and it is more or less pubescent. In addition to
the chasmogamous (insect-pollinated) flowers that have been described,
sometimes smaller cleistogamous (self-fertile) flowers are produced.
The blooming period occurs during the late spring or summer.
Afterwards, fertile flowers are replaced by 6-valved seed capsules that
are about ½" across at maturity and more or less globoid in shape. The
outer surface of each seed capsule has 6 fine ridges along its outer
surface that are equidistant and longitudinal. Eventually, these seed
capsules split open to release their seeds (there are about 48 seeds
per capsule). These seeds are 4-5 mm. long, compressed-obovoid in
shape, and brown. The root system consists of a short knotty rhizome
that has abundant fibrous roots below.
preference is light to medium shade, mesic conditions, and a loamy soil
with decaying organic matter (e.g., fallen leaves). As the flowers are
not conspicuous, this is primarily a foliage plant for shade gardens or
restoration of woodland habitat.
Virginia Snakeroot is uncommon to occasional in most areas of Illinois,
except in the NW section of the state, where it is absent (see
The typical variety of this plant (Aristolochia
) occurs in all of the areas that
while the narrow-leaved variety (Aristolochia
restricted to the southern tip of Illinois, where it is rare. Illinois
lies near the northern range-limit of this plant. Habitats include rich
woodlands, upland rocky woodlands, wooded slopes, and wooded ravines.
This is a conservative species that is normally found in higher quality
woodlands where the original ground flora is intact. It usually
occurs in the forest understory as scattered solitary plants, rather
than in colonies.
The odd-looking flowers
are cross-pollinated primarily by flesh flies, fungus gnats, and
possibly carrion beetles. After entering the flowers, these insects
remain trapped in the calyx tube until the stamens mature, after which
they escape carrying some of the pollen on their bodies. The floral
reward of these insects is primarily nectar. The caterpillars of a
butterfly, the Pipevine Swallowtail (Battus philenor
feed on the foliage
of Virginia Snakeroot (Aristolochia
), although more than
one plant is required to complete their development. Because the
foliage and roots are toxic and unpleasant-tasting, mammalian
herbivores do not feed on this plant. The method of seed dispersal for
this plant is something of a mystery, although it has been speculated
that small rodents may carry the the seeds to caches, where they are
eaten as food. Because such rodents have short life spans, not all of
the seeds are eaten (Allard, 2002).
A woodland in southern Illinois. The
photographed plant is an example of the typical
variety, or Aristolochia
is possible to identify Virginia Snakeroot (Aristolochia serpentaria
by the shape of its leaves and its relatively low stature. The flowers
of this plant resemble those of Woolly Pipevine (Aristolochia
) and Dutchman's Pipe (Aristolochia macrophylla
the flowers of Virginia Snakeroot are smaller in size and they are held
much closer to the ground.
The latter two plants are much longer vines that are distributed
primarily in SE United States, although Woolly Pipevine also occurs as
a native plant in
the southern tip of Illinois. These two vines are also cultivated
occasionally. Some authors have assigned Virginia Snakeroot to the
Endodeca genus, although this classification is not universally
accepted. For example, Mohlenbrock (2014) refers to the typical variety
of this plant as Endodeca
, while the narrow-leaved variety
is referred to as Endodeca
. There is also disagreement about
whether or not plants with narrow leaves are worthy of status as a
variety or a distinct species.