Managing for sustainable timber harvesting Areas that are ecologically sensitive and could not recover from harvesting (unsustainable) should not be logged. This decision is based on the following: 1) Type and age of the tree (is the sustainability of the species threatened?) 2) Slope of land (will the removal of trees cause the soil to erode and pollute waterways? 3) Type of soil (will the soil have enough nutrients to support re-growth?) not possible in rain forests 4) Climate (is there appropriate amounts of rain and temperatures ranges for the forest to re-grow) (is there a change in the amount of light) 5) Wildlife (are there any endangered or threatened species? Is the wildlife sustainable?) 6) Surroundings (Location) will it affect nearby ecosystems such as streams and ponds? Does it fragment a larger ecosystem?