Description: This native annual plant is about
½–2½' tall and unbranched. The central stem is round and has
numerous white hairs. The opposite leaves are about 2" long and ¾"
across. They are broadly lanceolate and sessile against the stem, with smooth
margins and fine white hairs covering the upper and lower surfaces. Each of the
upper leaves usually have two small lobes at the base, which resemble ears. The
inflorescence consists of a spike of flowers in the upper half of the plant.
These flowers are purple, pinkish purple, or lavender. Each tubular flower is
about ¾" long, with 5 short lobes that flare outward. Sometimes there
are purple dots inside the corolla. The reproductive parts consist of 4 stamens
and 1 stigma near the upper inner surface of the corolla. Each flower is
subtended by a large green calyx that is hairy and divided into 5 triangular
parts. The blooming period occurs during late summer and lasts about 3 weeks. A
fruit develops within each calyx that contains numerous small seeds. At this
time, the entire plant becomes reddish brown. These seeds are probably
distributed by the wind to some extent. The root system consists of a central
taproot and secondary roots – the latter are often parasitic on the roots
of other plants, particularly Aster spp. However, in the absence of a
suitable host, Ear-Leaved False Foxglove can meet its own needs adequately
through photosynthesis.
Cultivation:
The preference is full or partial sun and mesic conditions. This plant
typically grows in rich, loamy soil. It appears to have few problems with
disease. The seeds can be slow to germinate; it is possible that a heat
treatment simulating the effects of a wildfire may be beneficial in this
regard.
Range & Habitat:
Ear-Leaved False Foxglove is a rare plant that occurs in scattered counties
throughout most of Illinois, except the extreme south (see
Distribution
Map). It is state-listed as a threatened plant. Habitats include mesic
black soil prairies, thickets containing grasses and occasional shrubs,
savannas, woodland borders, abandoned fields, and areas along railroads
(particularly where remnant prairies occur). This plant is found in both high
quality habitats and somewhat disturbed areas. It is intolerant of frequent
mowing or grazing; however an occasional wildfire may improve germination of
the seeds, as well as reducing competition from shrubs and other kinds of
plants. The species Aster ericoides (Heath Aster) and other aster
species of mesic black soil prairies are beneficial because they are suitable
hosts for the parasitic roots.
Faunal
Associations: Bumblebees are the most important pollinators of the
flowers, where they seek nectar. Other long-tongued bees also visit the
flowers, including Miner bees and large Leaf-Cutting bees. Little information
is available about this plant's relationship to mammalian herbivores; because
the foliage is not known to be toxic, it is probably consumed by them
occasionally.
Photographic Location:
The photographs were taken at a prairie remnant along a railroad in Iroquois
County, Illinois.
Comments:
Ear-Leaved False Foxglove is easy to identify because of the small lobes on the
upper leaves. The plant in the photographs was in fruit during the fall (late
September); photographs of the flowers are currently unavailable.