This section is from the book "A Manual Of Weeds", by Ada E. Georgia. Also available from Amazon: A Manual Of Weeds.
Introduced. Perennial. Propagates by seeds. Time of bloom: June to August. Seed-time: July to September.
Range: New Brunswick to New Jersey, and westward to Ohio. Habitat: Moist soil; meadows and waste places.
An escape from flower gardens, and a pernicious weed wherever established because of its perennial roots. Its seeds are said to have some of the same poisonous properties as those of its relative the Corn Cockle, but not to so dangerous an extent. (Fig. 95.)
Fig. 94. -Corn Cockle (Agrostemma Githago).
Fig. 95. - Ragged Robin (Lychnis Flos-cuculi).
Stem one to two feet tall, erect, slender, branching near the top, downy-hairy below, somewhat clammy above. Basal and lower leaves spatulate, tapering to a margined petiole; upper leaves sessile, few, becoming very small as they ascend the stalk. Flowers in loose, spreading panicles; those of plants cultivated in gardens usually pink, white or blue, but those of the wild plant usually magenta-red, nearly an inch broad, each of the five petals divided into four slender lobes, the middle pair of lobes being longest, causing the flower to have a ragged, fringy look; calyx short, ten-nerved, smooth. Capsule nearly globular, one-celled, many-seeded.
Means of control the same as for the Corn Cockle.