E Q U IS E T U M arvense.
Corn Horsetail.
CRYPTOGAMIA Filices.
G en. Char. Catkin composed of peltate scales,
flowering on their inside. Partial Calyx of 2
valves. Seeds numerous, naked, enfolded by 4
pollen-bearing filaments.
Spec. Char. Sterile stems branched in every direction ;
the branches roughish, with simple angles : flowering
ones unbranched ; their sheaths distant, with
broad deep teeth.
Syn, Equisetum arvense. Linn. Sp. PI. 1516. Sm.
FI. Brit. 1103. Huds. 447. With. 153. Hull.
233. Relh. 403. Sibth. 263. Abbot 222.
Curt. Land. fasc. 4. i. 64. Bolt. Fil. 62. t. 34.
E. arvense, longioribus setis. Raii Syn. 130.
/3.E. pratense, longissimis setis. Hill, in Raii Syn. 131.
I n low moist cornfields very, frequent, and according to
Mr. Curtis, very troublesome to the farmer, as being difficult
of extirpation, and noxious to cattle, especially kine. We
presume its action on their intestines may be chiefly mechanical,
considering the sharp rough angles and points with
which its whole form abounds, and the abundance of flinty
earth in its cuticle, which forms a file similar to, though
finer than E. hyemale, t. 915.
The root is creeping and perennial. In April it throws up
several simple, pale brown, smooth, juicy stems, a span high,
each encompassed with about 4, rather distant, furrowed,
brown-toothed sheaths, and bearing a terminal, upright, large,
ovate-oblong, brown catkin. The sterile stems appear some
time afterwards, and are much taller, jointed, furrowed,
rough-edged, beset from top to bottom with numerous,
whorled, simple, jointed branches, whose joints are deeply
furrowed, and the intermediate angles or ridges are simple,
one of them extending to the point of each tooth. The
variety /3 is but a trifling one; see Bauhin’s Theatrum 246.
The flowering stems of this plant were evidently mistaken
for our E . variegatum, t. 1087, by Mr. Lawson. See Raii
Syn. 130. n. 3.