field clover (Trifolium campestre)
large hop clover
big hop clover
lesser hop clover
low hop clover
Trifolium procumbens L.
CONFIRMATION STATUS: Pending confirmation.
TAXONOMY: The currently accepted scientific name for field clover
is Trifolium campestre Schreb. Until recently, Trifolium campestre and
Trifolium procumbens were treated as two separate species. However,
Trifolium procumbens has been reclassified as being a commiserate with
Trifolium campestre. Older field guides may refer to Trifolium procum-
bens as smaller hop clover.
NATIVE STATUS: Introduced, United States and Canada.
GENERAL BOTANICAL CHARACTERISTICS:
Habit: This introduced annual plant is up to 1' tall, branching frequently
and having a bushy appearance. The stems are green or reddish green and pubescent; they have a tendency to sprawl.
Leaves: The alternate leaves are trifoliate; they have long petioles that are hairless. The leaflets are ovate or obovate, hairless, and slightly dentate
along the margins. They have conspicuous pinnate veins that are straight,
but lack any white chevrons. The petiole of the middle leaflet is conspicu-
ously longer than the petioles of the lateral leaflets; the petioles of the lat-
ter are often sessile, or nearly so. Each leaflet is about ¾" long and half as
much across. From the axils of the upper trifoliate leaves, their develops individual flowerheads from pubescent stalks about 1" in length. Each of
these stalks is longer than the petiole of the adjacent trifoliate leaf.
Flowers: The yellow flowerheads are up to ½" across. They are more or
less spherical and consist of about 15-40 flowers. Each flower is about
1/6" long. It has 5 elongated yellow petals and a light green calyx that is
shorter than the petals and inconspicuous. The upper petal, or standard,
has an outer surface that is conspicuously grooved; it is parallel to the
keel (the lower petals) and functions like a protective hood. The petals of
the flowers are persistent, turning light brown or nearly white on the flow-
Fruit/Seeds: Each flower produces a single seedpod that is shorter than
the persistent keel.
Roots: The root system consists of a taproot, which can form nodules
on secondary roots to accommodate nitrogen-fixing bacteria. This plant
spreads by reseeding itself, and often forms colonies.
REGENERATION PROCESS: Field clover propogates itself
HABITAT TYPES: Habitats include savannas, abandoned fields, pas-
tures, edges of paths, degraded meadows with a history of disturbance,
and vacant lots. This species is occasionally grown for forage or to reju-
venate cropland. It prefers disturbed grassy areas, although it occasionally
invades natural areas to a limited extent. Low hop clover was introduced
into the United States from Eurasia.
SITE CHARACTERISTICS: The preference is full or partial sun, moist
to mesic conditions, and a loam or clay-loam soil. It appears to favor fer-
tile soil that is not too dry.
SEASONAL DEVELOPMENT: The blooming period occurs during the
summer and lasts about 1-2 months.
GENERAL DISTRIBUTION: Since being introduced in Pennsylvania
as a forage plant, field clover has rapidly spread throughout much of the
United States and Canada. Except for parts of the southwest and Rocky
Mountain region, and the Prairie provinces of Canada, field clover is one
of our most common clovers.
SKY MEADOWS DISTRIBUTION: To be determined.
IMPORTANCE AND USES: The flowers are pollinated primarily by
various kinds of bees, which seek nectar and pollen. Beeflies, small butter-
flies, and skippers may visit the flowers as well. The caterpillars of several
Colias spp. (Sulfur Butterflies) feed on Trifolium spp. (Clovers), as do the
caterpillars of numerous moths. Upland gamebirds feed on the seedheads
and foliage of clovers, including the ring-necked pheasant, greater prairie
chicken, and wild turkey. The foliage and seedheads are also eaten by
various small mammals, including the cottontail rabbit, groundhog, thir-
teen-lined ground squirrel, and meadow vole.
Field clover is good for pastures because of their nutritional quality and
nitrogen fixing abilty. Although this plant is a weedy plant, it is still valu-
able as a soil builder. Field clover displays rapid spring grow- th and is
usually locally plentiful in the Eastern U.S.
Crooked Run Valley