Bi2 HAY AND FODDER. 
Four species have been experimented with and found 
-to be harmful. One of these, Equisetum hyemale L., the 
Scouring-rush or Winter Horsetail, can be dis- 
ewan tinguished from the other three by the fact that 
pecies ¥ sane 
it has an evergreen stem. This is usually un- 
branched and of considerable size, sometimes half an 
inch or more in diameter and several feet high. The other 
three species are all much branched. One, Equisetum 
sylvaticum. L., is found almost exclusively in or at the 
border of rather shady woods. It is a slender form with 
characteristically leaning stem and gracefully drooping 
whorls of branches. Another, E'quisetum palustre L., is 
practically confined to open wet places. It has rather 
stout 4 to T-angled, hollow branches. The above species 
cause less trouble in this country than the fourth, which 
is known as the Field Horsetail, Equisetum arvense, be- 
cause of its usual habitat. This form, as stated above, 
has separate fruiting stems which come up early in the 
spring and bear the spore cones at their tips. Later the 
green branched form appears, no fruiting cones being 
ever found on it. It is widely distributed and more abun- 
dant than any of the other forms. It can be distinguished 
from Equisetum palustre by its solid 3 to 4-angled 
branches and by the larger cavity of its stem, this being 
one-half to two-thirds of the diameter in Equisetum 
arvense and about one-sixth in Equisetum palustre. From 
Equisetum sylvaticum it'is ordinarily distinguishable by 
its much less abundant and less conspicuous secondary 
branching. Great numbers of secondary branches do oc- 
cur, however, on the Field Horsetail when its main stem 
has been eaten or broken off. Then the whole aspect of 
the plant is changed, and it assumes a low bushy form 
that is even more distinct from the slender, graceful 
woodland species. 
