Heidi and great friend Arnold testing Blast-Off.  Go to the product to see the results.  Best gutter cleaner I have ever see.  Blast-Off is a super-concentrated degreaser designed for cleaning professionals, but safe for home use.  Blast-off easily cleans oils from asphalt and concrete, and all aggragate surfaces.  Great for degreasing parking lots and parking garages, toll plaza lanes, driveway, building, dumpster pads,  greasy commercial kitchen floors and much more!