Description: This native perennial plant is 2–3½' tall, branching occasionally in the upper half. It is more or less erect, although the weight of the inflorescence often causes the stems to lean sideways. The stems are round and slender, often with lines of small white hairs. The alternate leaves are up to 6" long and 2" across, becoming gradually smaller as they ascend the stems. Their petioles are very slender and about 1" long on the lower leaves, while the upper leaves are nearly sessile. The petioles are often hairy. The lower leaves are narrowly cordate with heart-shaped bases, while the upper leaves are narrowly cordate or lanceolate. The upper surface of each leaf is smooth and hairless (not rough), while the lower surface is often covered with fine short hairs, especially along the central vein. The lower surface of the leaves also has a reticulated network of fine secondary veins. The leaf margins are smooth, or nearly so.
The upper stems terminate in panicles of
composite flowers up to 1' long. Each composite flower is about
¾–1" across, and consists of 10-20 ray florets that surround
numerous disk florets. The ray florets are lavender or pale blue-violet, while
the disk florets are initially yellow, becoming reddish purple with age. On
unusual specimens, the ray florets are light pink or white. The overlapping
involucral bracts are narrow and finely pubescent. Each bract has a small dark
green diamond toward its tip. The blooming period occurs from late summer
through the fall, and lasts about 1–1½ months. Both the ray and
disk florets can produce fertile seeds, each equipped with a small tuft of
light brown hair. They are distributed by the wind. On mature plants, the root
system consists of a caudex with coarse secondary roots, and short rhizomes are
occasionally produced. This plant can form small vegetative
colonies.
Cultivation: The
preference is partial sun, mesic to slightly dry conditions, and a woodland
soil that is loamy or rocky. Calcareous ground with a higher than normal pH is
tolerated. Like many other asters, the foliage can be attacked by insects or
disease. The plants have a tendency to flop over while in
bloom.
Range & Habitat: Short's
Aster is a fairly common species that occurs in the majority of counties in
Illinois. It is less common in some southern areas of the state (see
Distribution
Map). Habitats include mesic to slightly dry woodlands, rocky open
woodlands and slopes, limestone bluffs, and woodland borders. This species
occurs in both oak woodlands and maple-basswood-elm woodlands. It often occurs
in areas where limestone is close to the surface of the ground, and is usually
found in high quality habitats.
Faunal
Associations: The flowers of Aster spp. attract many kinds of
insects, especially long-tongued bees, small-tongued bees, butterflies,
skippers, and flies. These insects seek nectar or pollen. The foliage is a
source of food to many kinds of insects, including the caterpillars of the
butterflies Chlosyne nycteis (Silvery Checkerspot) and Phyciodes
tharos (Pearl Crescent). The list of moth caterpillars that are known to
eat various parts of Aster spp. is a long one (see
Moth Table). The Wild Turkey
eats the seeds and foliage of Asters in woodland areas to a minor extent. The
rather smooth foliage of Short's Aster is undoubtedly eaten by White-Tailed
Deer and the Cottontail Rabbit occasionally.
Photographic Location: A woodland edge near Busey's
Woods in Urbana, Illinois.
Comments:
This is one of the more attractive woodland asters with flowers that are larger
than average in size. Short's Aster can be distinguished from other Aster
spp. by carefully considering the appearance of the foliage and the size of
the flowers. The lower to mid-level leaves are cordate (indented) at the base
with narrow petioles. Some Aster spp., such as Aster
sagittifolius (Arrow-Leaved Aster), have winged petioles on their lower to
mid-level leaves. The margins of the leaves in Short's Aster are devoid of
teeth (or nearly so), while other woodland asters, such as Aster
cordifolius (Blue Wood Aster), have leaf margins with conspicuous teeth. In
Short's Aster, the middle and upper leaves beneath the inflorescence are
cordate or broadly lanceolate, while in Aster spp. that are adapted to
sunnier areas the corresponding leaves are lanceolate or linear – an
example from this latter group is Aster oolentangiensis (Sky Blue
Aster). Similarly, the upper surface of the leaves in Short's Aster is hairless
(or nearly so), while in Aster drummondii (Drummond's Aster), the upper
surface of the leaves is pubescent. Finally, the composite flowers of Short's
Aster are often ¾" across or more, while the composite flowers of other
woodland asters are usually less than ¾" across.