Coiling of Underground Shoots of Convolvulus arvensis

Abstract

THE shoots ascending from the rootstock of Convolvulus arvensis, before they reach the surface of the ground, are frequently found to be coiled. The coils vary in diameter from one to two inches or more, and lie closely adpressed upon one another. A considerable length of shoot, in some cases three or four feet, is thus compressed into a small space. No object has been found enclosed by the coils which would serve as a stimulus; the soil contains very few stones to obstruct the straight upward growth of the shoots. In a few cases a similar coiling has been observed in the ascending shoots of Carduus arvensis. One of the “popular” names of Convolvulus arvensis is “Devil's Corkscrew.” These white corkscrew coils of the shoots underground seem more likely to be the origin of the name than the less noticeable above-ground coiling portion.