I am a warm, wet area that has a lot of trees.

This is how loggers affect the forest.

I am liquid, molten rock.

This is the reason Washington receives a lot of rainfall.

I am the process of cutting down and transporting trees from the forest.

This causes the Pacific Coast to have earthquakes.

I make soil better for growing crops.

I am the mountain range found in the Western States region.

I am an irrigation system.