Carson’s discussion of dutch elm disease leads her to advocate “the conservation of variety”. what does she mean by this?

Carson means this is good because it helps prevent disease without needing to spray chemicals. The most effective control of Dutch Elm was removing diseased trees, and that spraying improved the situation. The more different species of trees in an environment, the more opposition to disease the forest will have. The elm tree is a communal tree embedded all through the united states. Dutch elm infection eradicates off elm trees. It is range by the elm bark insect. One indication of dutch elm disease is if your elm tree will start to perish. Several american elm alive nearby peterborough ontario but one supposes a life span of only about 30 years. 

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