Sentence:  However, don't get it confused with a watershed, warns Burgess, because a <WSD>fibershed</WSD> must necessarily cross multiple topographic boundaries to work ecologically and economically. Right now, that means stretching the definition of "local" way out -- at least until sustainable fiber production takes off. 
Meaning of the word marked with <WSD> tags:  The geographic region from which come all of the resources to make an article of clothing.