Agrostemma Githago L—Corncockle
FAMILY: Caryophyllaceae—the Pink Family
This family is an economically important group because of the large number of ornamental plants it contains. These include the florist's carnation, baby's-breath, maltese cross, sandworts, pinks, and others. Only corncockle (Agrostemma Githago) and bouncing Bet (see Saponaria) are poisonous; both are common in Pennsylvania. Characteristics of the family include: opposite leaves; petals: distinct, 5 (sometimes none); sepals: separate or connate, 5; stamens: 1-10, commonly twice as many as the petals; ovary: superior, 1- to 3-celled, mostly 1-celled with ovules (and seeds) attached to a central basal column that is not fused to the top of the ovary; stigmas and styles: 2-5; fruit: a capsule, opening at the apex by valves or teeth of the same number (or twice the number of the styles); stem: often swollen at the nodes.
PHENOLOGY: Corncockle has an extended flowering period, July through September.
DISTRIBUTION: Agrostemma Githago is widely established as a weed of grainfields and waste places. Infrequently it is cultivated as a garden plant. The seeds are difficult to separate from wheat seeds and may contaminate this product.
PLANT CHARACTERISTICS: Stems: often 1 m, thinly hairy to silverish; leaves: 8-12 cm x 5-10 mm, without petiole or stipules, linear or lanceolate; Flowers: red, conspicuous; on pedicels to 2 dm, solitary at the ends of branches; calyx: fused 12-18 mm; 5 calyx lobes 2-4 cm long; petals: 5, each 2-3 cm long, notched at the apex; styles: 5; stamens: 10; Fruit: 14-18 mm, the capsule bearing numerous black seeds; seeds: covered with small warts and pits.
POISONOUS PARTS: The seeds are primarily responsible for poisonings from corncockle, however, all parts are suspected to be toxic. Seeds consumed at a concentration of 0.2-0.5% of body weight are lethal to young poultry; older birds are less susceptible.
SYMPTOMS: The toxic response includes severe gastroenteritis, acute stomach pain, vomiting, diarrhea, dizziness, listlessness, weakness, and slow breathing.
POISONOUS PRINCIPLES: The toxin is primarily the sapogenin githagenin, which may be 5- 7 % of the weight of seeds.
CONFUSED TAXA: In our area few members of the Caryophyllaceae have large, red flowers. Some Lychnis species superficially resemble Agrostemma, but in Lychnis the petals are appendaged and the calyx lobes are much shorter than the tube. Agrostemma petals lack an appendage, and the calyx lobes are longer then the calyx tube, often surpassing the petals
SPECIES OF ANIMALS AFFECTED: Poultry, horses, and other livestock are susceptible. In animals that vomit freely (e.g. pigs), acute poisoning is less likely.
TREATMENT: (11a)(b); (26)
OF INTEREST: Flour milled from wheat contaminated with corncockle has caused human poisonings. Current agricultural methods have largely eliminated this problem.