Colorado Plants Injurious to Livestock 
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Figs. 6- 7.—Horsetail or scouring rush; 6, early spring stems arising from underground 
stem; note fruiting cones; 7, branching form which appears later than the preceding. 
as 10,000 feet. It commonly grows in sandy places, along railways, 
roadsides, and in low meadows. In meadows, it may become so 
abundant as to injure the hay. It is here that it gives the greatest 
amount of trouble. 
The smooth scouring rush (Bquisetuin laevigatum) is ever¬ 
green. The stem's are stout and often reach a height of 5 feet. 
They may be branched or unbranched. This plant grows all over 
