Here's the link to the Taos city ordinance that specifically states no signs on public property, and that placement on private property must be with permission of the property owner. Also, a private property owner may take down any improperly placed signs on is or her property.
http://www.sterlingcodifiers.com/codebook/index.php?book_id=602
I can't link to the actual chapter, but clicking on Title 12, then chapter 28 (Advertising) will get you there.