Some species of
Parmotrema can be used as a vegetable dye, such as
P. crinitum. When mixed with pine sap or with water, or when first burnt to ash, lichens can provide a variety of colors such as yellow, brown, green, orange, purple, and red. Some
Parmotrema species also enter commerce as part of the lichen mixture known as "black stone flower", which is sold for culinary use under several regional names. Continued large-scale harvesting of commercially traded lichens may add to extinction risk when combined with
habitat loss and
climate change. ==Gallery==