henbit (Lamium amplexicaule)
Lamium amplexicaule var. album A. L. & M. C. Pickens
CONFIRMATION STATUS: Pending confirmation.
TAXONOMY: The currently accepted scientific name of henbit is
Lamium amplexicaule L. Henbit is another common weed from Eurasia
that occasionally makes a nuisance of itself. It is easy to identify because
of the sessile orbicular leaves that appear to wrap around the sprawling
stems. Other Lamium spp. (dead nettles) are more erect plants; their up-
per leaves don't wrap around the stems. Another plant that resembles hen-
bit somewhat is Glechoma hederacea (ground ivy). The leaves of ground
ivy always have petioles, and its flowers occur in smaller clusters from
the leaf axils. These flowers are violet-blue or purple and rather broad
with conspicuous side lobes, while the more narrow flowers of henbit
are pink and lack such side lobes. The common name 'henbit' refers to
the seeds, which presumably can be eaten by chickens.
NATIVE STATUS: Introduced, United States and Canada.
GENERAL BOTANICAL CHARACTERISTICS:
Habit: This adventive plant is a winter annual or biennial, branching frequently near the base. The green or reddish brown stems are 4-angled, nearly glabrous, and up to 2' long. They have a tendency to sprawl across
the ground, although the new growth of the stems is more erect.
Leaves: The opposite leaves are up to 1" long and across, occurring at inter-
vals along the stems. The plant has two types of leaves. The lower leaves have long petioles and are not associated with the flowers, while the upper leaves where the flowers occur are sessile (not stemmed) and wrap around the stems and located just below the flower clusters.. Leaves are orbicular, crenate, and/
or palmately lobed; these lobes are shallow, but cleft. The upper surface of the leaves has conspicuous palmate venation and is slightly hairy.
Flowers: The stems produce axillary and terminal whorls of 6-12 sessile flowers where the sessile leaves occur. Each tubular flower is about ½" long and semi-erect. The corolla of this flower is long and narrow at the base, be-
coming broader with two spreading lips. The upper lip is shaped like a hood with a patch of fine hairs on its outer side, while the lower lip hangs down-
ward. This lower lip is narrow at the base, but become broader and divided into two rounded lobes along its outer edge. The outer surface of the corolla is pink to purplish pink, while its inner surface is white with a few purplish pink
dots. The green calyx is slightly hairy and has 5 narrow teeth; it is much
shorter than the corolla. In addition to these insect-pollinated flowers, henbit
also produces inconspicuous cleistogamous flowers occasionally.
Fruit/Seeds: Each flower is replaced by 4 nutlets. Each nutlet is 3-angled, oblong, and somewhat broader and more rounded at one tip than the other. Its
surface is greyish brown with small white speckles.
Roots: The root system consists of a shallow taproot that becomes finely branched. This plant reproduces by reseeding itself, or it can reproduce vegetatively by the stems rooting at the nodes. Unlike many of its relatives, henbit does not have a strong or distinctive odor.
REGENERATION PROCESS: Hen-bit reproduces by reseeding itself, or it can reproduce vegetatively by the stems rooting at the nodes.
HABITAT TYPES: This plant is native to Eurasia and Africa. Habitats
include fields, pastures, gardens, nursery plots, edges of yards, lawns,
waste areas, and areas along buildings. There is a strong preference for
disturbed areas. Henbit can spread aggressively.
SITE CHARACTERISTICS: Typical growing conditions are full or partial
sun and moist to mesic soil that is loamy and fertile. Plants become dormant
during the hot weather of summer.
SEASONAL DEVELOPMENT: The blooming period occurs primarily dur-
ing the spring and lasts about 1-2 months; some plants also bloom during the
fall for about a month.
GENERAL DISTRIBUTION: Henbit is found in all states in the continental
United States and nearly all of the Canadian provicnes (absent in some regions of the northern territories).
SKY MEADOWS DISTRIBUTION: To be determined.
IMPORTANCE AND USES: The nectar and pollen of the early blooming flowers attract long-tongued bees primarily, including honeybees and bumble-
bees. The foliage is eaten by voles and box turtles, while rabbits rarely bother it.
Henbit provides valuable erosion control in many cropland fields of the
southern U.S., though it is also treated as a weed throughout the U.S.
Crooked Run Valley