Yes, they can do this assuming that there is any ordinance or code in effect in your county or municipality stating that there are standards for yards, or that excessive debris or clutter have to be cleaned up, etc.--and there most likely is: most areas have such code or ordinances. They do not need to give you an extension (though you can, of course, ask for one); you may need to hire a clean-up service (or at least some local teens, preferably ones with a truck or van) to help you.