Eastern green mambas occupy coastal forest and dense thicket and move through the canopy rather than across the ground. The body is laterally compressed and lightly built, the tail is long and prehensile enough for bridging between branches, and animals descend mainly to cross gaps or to reach a new tree.
The colour is camouflage rather than warning. Under a broken canopy the uniform bright green with a yellowish belly dissolves into sunlit foliage, and the snake's usual response to disturbance is to freeze or to slide quietly away rather than to display. Sightings are correspondingly rare relative to how common the species is in suitable habitat.
The species is often conflated with the western green mamba and with the far more terrestrial black mamba, and bite records are muddled by that confusion. Its venom contains dendrotoxins and is medically significant, but the rarity of encounters means bite series are small and clinical descriptions remain thinner than for the black mamba.