6. Producer from a Temperate Deciduous Forest Biome

Some animals, like birds, use lichen to decorate there nests. Others, like deer and caribou, eat the lichen. Lichen is mostly eaten in the winter when food is limited for some animals. This plant is also helpful as a free water source. Lichen also helps in controlling soil erosion.

(http://www.lichen.com/fauna.html)

What are some disadvantages to lichen?