Deforestation is the name for chopping down trees. Diggers and wood cutters cut down trees to build and make tools and materials such as tent poles, mine supports and fire wood. Deforestation was a big problem during the gold rush and still is today. The reason this was a negative impact is because, chopping down trees kills trees and chopping down trees kills the homes of animals such as birds. Trees also provide shade for plants that can't recieve much sunlight. Deforestation was deffinately a negatave impact on the environment.