I use to have tree trimming crews drop off their loads of chips here, But had to stop them, when they began delivering so much trash from their lunches and from the jobsite mixed in the chips. If you can talk to a crew trimming in your area, you may be able to get plenty of free chips, just be prepared to clean up some trash from the chips, and hope it is not excessive! Be sure and have them dumped were they will not hurt anything, as the fresh chips will kill the grass and sometimes close plantings, when piled up to age. Also, poison oak and other noxious things may be present in the load as they chip whatever is cut, regardless of what it is, or what is clinging to it! I had a neighbor, whose two kids got hospitalized from throwing wood chips on a campfire at their weenie roast that was laced full of poison oak! They were in intensive care, with breathing tubes as all their body orifices swelled shut. They could not defecate, urinate , breathe or swallow without medical intervention. Apparently, the smoke inhalation and hand to body contact had caused critical systemic poisoning!