rond de sorcière

OBS: Maladie des gazons causée par un champignon.
OBS: Cette forme régulière provient d'un égal développement du mycélium dans toutes les directions, à partir du point où la spore avait germé, [...]

CONT: A large number of thatch-and-soil-inhabiting basidiomycetes cause fairy rings in turfgrasses. ... Symptoms: In the spring and early summer, circular or arc-shaped rings of darker green or faster growing grass may appear in moist turf. These bands of lush turf may be 10-20 cm wide. A concentric ring of thin, dormant, or dead grass may develop inside the circle of lush grass. Occasionally, a second zone of stimulated grass occurs inside the zone of plant death.