Description: This native perennial plant is about 3-5'
tall, branching frequently in the upper half. The green stems are glabrous and
slightly ribbed or furrowed. The alternate leaves are up to 6" long and
¾" across, becoming smaller and more narrow as they ascend the stems.
They are narrowly lanceolate or oblanceolate, smooth along the margins, and
glabrous; the uppermost leaves are linear. Each leaf tapers gradually to a
petiole-like base. The upper stems terminate in showy panicles of white
flowerheads; these flowerheads are produced in abundance. Each flowerhead is
about ¾" across, which has up to 60 white ray florets surrounding
numerous yellow disk florets (less often, the ray florets may be pale pink or
pale violet). The base of the flowerhead is shallow and spreading, rather than
cylindrical; it is covered with green floral bracts that are lanceolate in
shape. The blooming period occurs from late summer into the fall and lasts
about 1 month. Each floret is replaced by an oblongoid achene that is somewhat
flattened; it is slightly broader at the apex than the bottom. The apex of the
achene has minute scales and a pair of bristles, although the bristles are not
always present. The achenes usually fall only a short distance from the mother
plant. The root system sometimes produces stolons that form plantlets at their
tips.
Cultivation: The preference is
partial or full sun, wet to moist conditions, and a fertile loamy soil. This
plant can tolerate standing water for short periods of time and doesn't seem to
be bothered by foliar disease to the same extent as many Aster spp.
(Asters).
Range & Habitat: False
Aster occurs occasionally in most areas of Illinois; it is slightly more common
in southern Illinois than other areas of the state (see
Distribution
Map). Habitats include openings in floodplain forests, soggy thickets,
alluvial meadows, poorly drained areas of black soil prairies, marshes, and
ditches.
Faunal Associations: The
flowers attract many kinds of insects because the nectar and pollen are readily
accessible. These insect visitors include long-tongued bees, short-tongued
bees, wasps, flies, butterflies, skippers, moths, and beetles. The Dagger Bee,
Perdita boltonia, is an oligolege of Boltonia spp. Another bee
that is somewhat oligolectic of these species is the Miner Bee, Melissodes
boltonia, which also visits the flowers of some Aster spp. Aside
from these flower-visiting insects, little else appears to be known about the
floral-faunal relationships of this and other Boltonia
spp.
Photographic Location: A
poorly drained area of prairie at Meadowbrook Park in Urbana,
Illinois.
Comments: False Aster has
attractive foliage and flowers. Different varieties of False Aster have been
described; the one that is typically encountered in the state, var.
recognita, has flowerheads about ¾" across. In Cook County, var.
microcephala also occurs, which has flowerheads that are ½" across
or less. While Boltonia spp. (False Asters) closely resemble Aster
spp. (Asters) in appearance, they differ from each other in the following
characteristic: The achenes of False Asters have minutes scales or a pair of
bristles at their apex, while the achenes of Aster have tufts of hair. As a
result, the achenes of Asters are carried more readily by the wind into new
areas. The other False Asters in Illinois are uncommon and differ from
Boltonia asteroides by their leaves: Boltonia diffusa interior
has linear leaves throughout, while Boltonia decurrens has leaves that
are decurrent against the stem (i.e., the base of each leaf lies along the
surface of the stem).