Do you remember the hydrological cycle that you learned about in school?

Rain and snow fall from the sky. Tree leaves and branches slow the fall of rain. In the spring, snow slowly melts, the melt slowed because trees shade the snow and cool the air. Some of the rain and melted snow infiltrate deep into the ground, aided by the presence of tree roots, to become part of the ground water that flows downhill, slowed by tree roots. Some rain and melted snow run off directly into creeks which flow into rivers and lakes and finally into the ocean. Transpiration from tree leaves, and evaporation from the land, lakes and ocean return the water to the sky and the cycle starts over again.

But wait. Remove a major part of the trees from the cycle and what happens? Rain and snow land directly on the ground. Less rain infiltrates the soil and, with no tree roots, what ground water there is flows downhill more quickly.

In the former forest, now a recent clear cut, there is no shade and no cooler air. Now the snow melts more quickly, infiltrates less into the soil, producing a shorter, more intense spring run-off, increasing the probability of spring floods and landslides, and summer droughts. The drier clear cut areas combined with more........

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