"most plastic, aside from the ubiquitous clear plastic bottle, cannot, generally speaking, be recycled by most municipalities"

http://discovermagazine.com/2009/jul-aug/06-w...nvironment

"One type of unrecyclable plastic steadily growing in use is low density polyethylene (LDPE) agricultural plastic film. LDPE agricultural film is gaining in popularity as an alternative for more traditional methods of storage. It can be found in agricultural operations as silo bunker covers, silage bags, bale wrap, greenhouse covers, haylage covers, row covers, and mulch film."

http://cwmi.css.cornell.edu/agwaste.html