The most common snakes with black and orange coloring are orange-striped ribbonsnakes, corn snakes and ringneck snakes. These species are all nonvenomous and harmless to humans.
Ribbonsnakes have orange to yellow stripes running the length of their bodies. The upper body is otherwise black except for a yellow or orange spot on the head, while the underside is greenish or cream-colored. These snakes are 20 to 30 inches in length.
Corn snakes are longer, growing up to 72 inches. They are usually orange to brownish-yellow in color with darker splotches bordered in black along their backs. A corn snake's belly has alternating black and white markings.
Ringneck snakes are usually grayish but can be nearly black and have a single orange or yellow band just behind the head. Their bellies are yellow to orange. They generally measure no more than 15 inches in length.