Monographs Details: Hippochaete laevigata Farw.
Authority: Farwell, Oliver A. 1916. The genus Hippochaete in North America, north of Mexico. Mem. New York Bot. Gard. 6: 461-472.
Family:Equisetaceae
Description:Distribution and Ecology - Keweenaw Peninsula, Mich., Farwell 3994 1/2, June 29, 1915. Algonac, Mich., Farwell 3640, 3684 1/2, 3685, June 21, 1914. Detroit, Mich., Farwell 210e, June 24, 1902. Rochester, Mich., Farwell 210c, July 4, 1896; 3721 1/2, July 19, 1914. Stony Creek, Mich., Farwell 3438 1/2 June 8, 1913. Parkedale Farm, Mich., Farwell 2701, June 11, 1912; 3677 1/2, June 11, 1914; 3705, June 28, 1914. Common west of the Mississippi and in the "Lake States."

Discussion:

Equisetum laevigatum A. Br. Am. Jour. Sci. 46: 87. 1843.

This species in its typical form is well characterized by its simple or branched, annual, stems, which are smooth, at least to the touch, its rounded spikes, and campanulate sheaths with caducous teeth. Those varieties which are intermediate between this and other species generally will have rough stems and spikes that are either obtuse or apiculate. It may be found in clear sand or gravel, or a similar soil covered with a sparse growth of grass and other vegetation and generally not far from water.

It may be found in colonies by itself, or it may be associated with H. prealta and its variety affinis, H. variegata, and Equisetum limosum. The vallecular bast divides the green parenchyma into y-shaped divisions. Eaton restricted this species east of the Mississippi to Ohio, Indiana, Illinois, and Wisconsin; but I have found it in southeastern Michigan, where it is common, and on the Keweenaw Peninsula, where it cannot be said to be scarce. Probably it is to be found throughout the state. The annual stems begin their growth about the first of May, are fruiting in June, and perish in July or August. New stems are appearing continuously until the middle of the summer but all have perished before winter has set in. It may be noted here that growth in the evergreen species begins, in Michigan, about the middle of May and continues through the summer.

Distribution:United States of America North America|