Green colour does not tell you whether a snake is harmless or dangerous. It is a useful camouflage colour in many habitats, but it is not a reliable identification feature. A safe response to any unfamiliar snake is to observe from a distance and identify it through a local expert or trusted regional guide.
Why colour can mislead
North American rough and smooth green snakes are nonvenomous, but green-coloured snakes in other parts of the world can be medically significant. Even within one region, lighting, age, and pattern can make colour a poor clue. Head shape and social-media photos are also unreliable shortcuts.
What to do instead
Keep a respectful distance, do not try to move or pick up the animal, and note the location from a safe place. If identification is needed, use a regional wildlife authority, a reputable local herpetological organization, or a qualified wildlife professional. This protects both people and the snake.
A better way to frame the myth
Green snakes are neither universally harmless nor universally dangerous. The species, its location, and the situation matter far more than colour.
