The gray stringy lichen hangs from trees that grow where the climate is cool and humid and where there is little sun. Lace lichen does not harm the trees; it is found on the branches that have already died from lack of sunlight. A lichen is combination of a fungus (the framework) and a green alga (the food producer) Both alga and fungus benefit by the association. Deer like to eat the lichen and birds carry it off for nesting matterials.