The effects of eliminating the natural forest cover are shown in the gullied farm lands and widened stream channels found in some densely settled areas. Partly because the stream channels are more or less filled with material washed down from the uplands, and partly because storm runoff has increased, the channels are today no longer able to carry all the flow from heavy rains. This explains why the streams overtop banks far more often than in the days before settlement.
26. The best title for the selection would be______.
A. River Rising! River Rising! B. Forests and Floods
C. Flooding in the U. S. D. The Results of Flooding
27. All of the following cause floods EXCEPT______.
A. heavy rain B. melting snow
C. increasing storm runoff D. porous soil
28. The author states that______.
A. lakes and swamps once acted like natural reservoirs
B. up-and-down hill plowing catches and stores water
C. stream channels are the best carriers of water
D. floods are easily prevented and controlled
29. According to the selection, streams overtop their banks partly because______.
A. material from higher land is washed into them
B. ditches and drains lead into them
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