Ohio Perennial and Biennial Weed Guide

Family:

Pink Family (Carophyllaceae)

Other Names:

Lychnis alba, Melandrium album, Silene alba, Silene pratensis, Silene latifolia ssp. alba, bladder campion, bull rattle, evening lychnis, snake cuckoo, thunder flower, white cockle, white robin, .

Origin and Distribution:

White campion was introduced into North America from Europe in the early 1800's most likely in contaminated crop seeds. This species is now widespread in the northern half of the U.S. and southern Canada. It is commonly found in grain, legume and vegetable crops, as well as in other disturbed sites, including field edges, roadsides, shorelines, wood edges and waste areas. White campion grows best in full sun on rich, well-drained soils.

Plant Description:

White campion can be a winter or summer annual, biennial, or short-lived perennial. This species is characterized by downy foliage and showy white flowers, whose petals emerge from a green, inflated, bladder-like structure (calyx). Reproduction is primarily by seeds, although fragmented segments of the root crown can give rise to new plants.

• Root System:

  White campion produces a fleshy taproot and thick lateral roots.

• Seedlings and Shoots:

  The two seed leaves (cotyledons) are yellow-green and lance-shaped. Young plants form a rosette of pale green, lance-shaped to oval, downy leaves.

• Stems:

  When rosettes bolt, erect stems are produced that grow 1 to 4 feet tall. Stems are round, leafy, branched, have swollen nodes, and are covered with short hairs. The upper portion of the stem may be slightly sticky. Several stems often arise from a single taproot and may become woody with age.

• Leaves:

  Leaves are opposite (2 per node), 1 to 4 1/2 inches long, lance-shaped to oval, and taper to a point. Short hairs cover the upper and lower surfaces and margins. Leaf margins may be slightly wavy. Upper leaves attach directly to the stem but lower leaves taper into long leaf stalks (petioles).

• Flowers:

  Showy, sweet-scented flowers are borne on long stalks, either in open clusters at the tops of stems or singly from the bases of upper leaves. Flowers are 1 inch wide with 5 white (or rarely pink) petals. Petals are deeply notched at the tips. Male and female flowers occur on separate plants, and are distinguished by the tube-like structure (calyx) from which the petals emerge: the female calyx is inflated, spherical, and green, with 20 lengthwise veins, while the male calyx is more slender, cylindrical, and purplish-green, with 10 lengthwise veins.

• Fruits and Seeds:

  A vase-shaped capsule (seedpod) forms in the inflating female calyx. The calyx disintegrates after the capsule is fully developed. The mature capsule is smooth, shiny, and light brown, with an opening at the top surrounded by 10 teeth. Each capsule contains numerous small seeds (1/20 inch wide). The brownish-gray seeds are rounded to kidney-shaped, slightly rough and flattened on one side.

Similar Species:

Corn cockle (Agrostemma githago) is similar but has red to purplish red flowers and narrower leaves. Night-flowering catchfly (Silene noctiflora), a summer annual, can be distinguished from white campion by its very coarse lower stem hairs, very sticky upper stem hairs, 6-toothed seedpods, and flower color (pink on top and yellow below). Bouncingbet (Saponaria officinalis) and bladder campion (Silene vulgaris) can be distinguished from white campion by their hairless stems and leaves. The rosettes of some asters (Aster spp.) resemble those of white campion but their stem leaves are alternate.

Biology:

Seedlings emerge in mid- to late spring and again in late summer. Biennial and winter annual forms remain as a rosette through winter and produce a flowering stem the following season. Short-lived perennial forms remain as a rosette for more than one season before producing a flowering stem. White campion blooms and sets seeds from late May until September. Flowers open at night and release a sweet scent, attracting moths for pollination. Each capsule contains approximately 500 seeds and one plant may produce 50 capsules in one season. Seeds require light to germinate, so it is possible that burying seeds in soil will decrease the number that germinate.

White campion can be difficult to control because of its high seed production and resistance to commonly used herbicides. Young plants do not tolerate cultivation. Regular cultivation may provide some control, but care should be taken to prevent any surviving plants from going to seed.

Toxicity:

None known.

Facts and Folklore:

• Members of the genus Silene were used in Elizabethan England to make a concoction with sugar and wine. This mixture was supposed to be soothing to the heart. The roots were used as worm medicine.

• Extracts from roots and leaves of white campion are extremely toxic to mosquito larvae.