IMPORTANT WESTERN BROWSE PLANTS 177 
Idaho to southeastern Oregon, California (east of the Sierras), 
and Utah. As a rule the species is not palatable to livestock, but 
Fleming reports that the buds and young leaves are frequently eaten 
by sheep in spring in Nevada. When eaten extensively it is apt to 
prove dangerous to sheep, at least at certain times of the year. The 
first definite report of this species being poisonous seems to have 
been an announcement to the press on June 16, 1917, by Doctor 
Mack, of the Nevada State Veterinary Control Service, to the effect 
that over 1,000 ewes and about 75 lambs had perished in the stock- 
yards of Reno, May 11-13, 1917, from eating this plant, and that he 
had administered 4 pounds of the tips of this species to a sheep which 
died about 45 hours thereafter, the post-mortem examination show- 
ing intestinal irritation, internal hemorrhages, dropsy, and degener- 
ation of heart, liver, and kidneys. Fleming and associates (34, 35, 
33, 37) state that sheep are the only livestock known to be pois- 
oned by the species; that the poison is a cumulative one; and 
that sheep must eat a large amount of the plant to be poisoned. 
Fleming fed four yearling cattle 1 to 8 pounds each of this plant 
without effect. 
Longspine horsebrush (7. axillaris, syn. T. longispina) (fig. 45), 
the tallest, longest spined and one of the most abundant species of 
the genus, occurring from Utah to California and Arizona, chiefly 
on alkaline low plains and hills, is a range pest. 
Nuttali horsebrush (7. nuttallii), a sharp, prickly shrub, 1 to 3 
feet high, of barren hills in Wyoming and Utah, has (according to 
Nelson, 92) its soft season’s twigs freely nipped off by sheep in 
the Red Desert of Wyoming. 
Shortspine horsebrush (7. spinosa), frequently called cotton 
thorn, another spiny species, with densely white woolly stems, 
ranges on dry hills, plains, and deserts between 4,000 and 7,000 feet 
from southern Idaho to eastern California, Utah, and Montana. 
Nelson states that it forms a valuable constituent of the winter forage 
for sheep and antelope in the Red Desert. 
Spineless horsebrush (7’. canescens inermis, syn. T. inermis) (fig. 
45), often called black sage, is an unarmed (spineless) species grow- 
ing on dry hills and plains, mostly at 4,000 to 9,000 feet, from western 
Montana to California, and New Mexico; it is probably the most 
widely distributed and familiar form of the genus. It is usually 
regarded as worthless or else poor winter feed. In the Modoc lava- 
bed region of northeastern California it has been reported by Leland 
S. Smith as poisonous to sheep. 
_ Chicory Subfamily (Cichorieae)™ 
SKELETONPLANTS (LYGODESMIA SPP.) 
This western genus, known also as bundletwigs and prairie pinks, 
consists of about six more or less herbaceous species, some of them 
having a woody root and crown and toughened, more or less indu- 
rated stems, thus partaking of an undershrubby character. The 
herbage of these plants is milky juiced and bitter or acrid and the 
palatability normally is relatively rather low. 
% This is the family Cichoriaceae of many authors. 
27259°—31——_12 
