(a) The action of any city officer or employe or of any public utility necessary to remove or alleviate an immediate danger to life or property; to restore utility service; or to reopen a public thoroughfare to traffic;
(b) An occupied parcel of private property consisting of less than 20,000 square feet of area;
(c) Felling of trees that are nuisances under section 6.010 of this code;
(d) Felling of trees that are in violation of section 7.640 of this code;
(e) Any felling necessary to install or maintain improvements such as streets and sewers within publicly owned and accepted rights-of-way or utility easements;
(f) That portion of a PUD and/or PUD subdivision development for which final approval has been obtained.