WEEDS 
of that plant. Its blossoms grow in small clusters from the 
axils of the leaves and are inconspicuous, but the triangular, 
dull-black seeds are quite distinctive; 
they resemble buckwheat and are diff- 
cult to remove from wheat. 
11. Common Thistles. — The com- 
monest thistle upon our northern prai- 
ries is the wavy-leaved thistle, which 
is native to the sod. It is covered all 
over with white, velvety fuzz, except 
perhaps on the upper surface of the 
older leaves. The height of the plant 
167 
is from 2 to 3 feet. The bull thistle ‘ \ 
or Scotch thistle came originally from ‘ 
Europe Witp BucKWHEAT 
Buti THISTLE 
andis not 
yet found in the more recently 
settled sections. It is taller 
than the wavy-leaved (3 to 5 
feet high), is more prickly, and 
the white woolly fuzz is almost 
completely absent. The tall 
thistle or roadside thistle is still 
taller (3 to 10 feet); the stem 
is downy; the leaves are rough- 
hairy above and whitened with 
close wool beneath. 
12. Canada Thistle. — This 
is one of the most pernicious 
weeds and is extremely difficult 
to eradicate. It is often found in dense patches, as it spreads 
from underground stems. 
It may easily be distinguished from 
