Forests are important habitats for birds and, in temperate forests, small mammals which inhabit the dense understorey.

对鸟类来说是重要的栖息地，温里，小型的哺乳动居住稠密的下层。

Tropical forest is wetter and usually supports only knee-high fires that spread slowly through the understorey.

热则较为潮湿，通常只能使火烧到及膝高度，并缓慢地下层植中蔓延。