Difference between emerald green Spectraflame and forest green Spectraflame.  These cars are examples of both shades of green.  The Custom Firebird is painted emerald green, while the Sugar Caddy is painted forest green.  Emerald green was used primarily from 1968-1970, although certain U.S.-made cars manufactured in 1971 and 1972 were painted in this color.  Forest green was used in 1971 and 1972 only.  The emerald green is more transparent than the forest green.