a. | Stipe very fragile, bending down before pileus expands; exclusively in lawns; stipe wall < 250 µm thick: C. lagopus var. vacillans |
b. | Stipe rather firm, upright; usually on wood-chips and vegetable-refuse; less frequent in lawns; stipe wall up to 450 µm thick: C. lagopus var. lagopus |