Description:
This herbaceous perennial plant develops 1-2 compound basal leaves
during the spring. The blades of these leaves are 3-7" long and 3-7"
across; they are ascending to more or less parallel with the ground.
Each leaf blade is divided into 3 leaflets (1 terminal & 2
lateral
leaflets). In less developed leaves, the leaflets are
pinnate-pinnatifid, ultimately dividing into narrow parallel lobes.
However, in more developed leaves, each leaflet divides into 3
subleaflets, and these subleaflets
are pinnate-pinnatifid, ultimately dividing into narrow lobes.
The ultimate lobes of these leaves are ¼–½" long and about 3 mm. (1/8")
across; they are
linear, linear-elliptic, or linear-oblanceolate in shape with entire
(toothless) margins and bluntly acute tips. The upper leaf surface is
grayish green to medium green, glabrous, and sometimes slightly
glaucous, while the lower leaf surface is white to greenish white,
glabrous, and very glaucous. For each compound leaf, the petiolule
(basal stalklet) of the terminal leaflet is longer than those of the 2
lateral leaflets. The petioles of the compound leaves are 3-6" long and
ascending; they are pale red to pale reddish green, terete, glabrous,
and often glaucous.
An inflorescence consisting of a raceme
of flowers sometimes develops shortly after the formation of basal
leaves. This
inflorescence is 6-12" tall and it is either erect or ascending. The
peduncle (basal stalk) of the inflorescence is pale red or pale
yellowish green, terete, glabrous, and glaucous. Each raceme has 3-10
pendant flowers. The corolla of the pendant flower is ½–¾"
long, mostly white, narrowly obcordoid in
shape, and somewhat flattened. Two fused outer petals form the rounded
nectar spurs (above), the lateral sides, and the pair of of upturned
lips (below) of the corolla. Two fused inner petals form a pair of
transverse crests and a pair of small inner claws near the entrance of
the
corolla. The small lips are shaped like keeled hoods with translucent
parallel veins. The flat crests are half-cordate in shape, slightly
wrinkled, slightly undulate, and white; sometimes they are pinkish
along their bases. Inserted within the corolla is a pistil
with a single style and several stamens. There are also a pair of tiny
sepals; they are about 2-3 mm. long, linear-lanceolate in shape, and
light pink with whitish margins. The nodding pedicels of the flowers
are pale green or pale reddish green, terete, glabrous, and sometimes
glaucous; they are up to ¼" long. At the bases of these pedicels, there
are solitary floral bracts about 3-5 mm. long; they are ovate to
obovate in shape and light pink with whitish margins.
The blooming
period occurs during mid-spring for about 2-3 weeks. The flowers have a
sweet fragrance. Afterwards,
fertile flowers are replaced by drooping seed capsules that become
about 12 mm. (½") long at maturity;
these capsules are ovoid in shape and somewhat flattened. Each capsule
divides into 2 parts to release its seeds; there are several seeds per
capsule. The seeds are 1-2 mm. long, short-reniform in shape,
and obscurely
reticulate; each seed has an attached elaiosome (food appendage). The
foliage dies down by mid-summer. The root
system consists of a cluster of yellow globoid corms and fibrous roots.
Cultivation:
The preference is dappled sunlight to medium shade, mesic
conditions, and a loose loamy soil with decaying organic matter. Growth
and development occur during the spring. Germination of the seeds can
be slow and difficult, although it may be possible to start new plants
by separating some of the corms. Insects and disease organisms are
rarely troublesome.
Range & Habitat: The native Squirrel Corn occurs
primarily in
NE, east-central, and the southern tip of Illinois, where it is
uncommon (see
Distribution
Map).
Illinois lies toward the western range limit of this
species; it is more common further to the east. Habitats include mesic
deciduous woodlands, wooded bluffs, wooded slopes, ravines, and shaded
stream banks. Squirrel Corn is found in high quality woodlands in
Illinois, where the native ground flora is intact. It is one of the
spring wildflowers that is threatened by the invasion of Garlic Mustard
(
Alliaria petiolata)
and some Eurasian shrubs, particularly Amur
Honeysuckle (
Lonicera
maackii).
Faunal
Associations: The flowers are cross-pollinated primarily
by
queen bumblebees. Both nectar and pollen are available as floral
rewards. The seeds are distributed to some extent by ants because of
their elaisomes (food appendages). Because the foliage is toxic, it is
usually avoided by mammalian herbivores. The overall value of this
plant to faunal wildlife is low.
Photographic Location: A deciduous woodland at Jim Smith's
farm in
Vermilion County, Illinois.
Comments:
This is another wonderful spring wildflower that can be found
in eastern deciduous woodlands. Both the foliage and flowers of
Squirrel Corn (
Dicentra
canadensis) are similar in appearance to those
of Dutchman's Breeches (
Dicentra
cucullaria). Both of these species
are found in similar habitats and their blooming periods overlap
(Squirrel Corn begins to bloom about 1 week later). However, Dutchman's
Breeches is by far the more common wildflower in Illinois. The flowers
of Squirrel Corn have short rounded nectar spurs, while those of
Dutch's Breeches are longer and more narrow. The basal leaves of these
two species are very difficult to distinguish, although those of
Squirrel Corn appear to have slightly longer ultimate lobes on average.
The corms of these two species are also different in appearance: the
corms of Squirrel Corn are yellow and globoid in shape, while the corms
of Dutchman's Breeches are pink and more ovoid in shape.