i copied this from a kentucky snake site but it's always good to keep in mind. Length The first question to ask is, "How long is the snake?" Imagine how long the snake is when it is stretched out. For example, small land snakes like the redbelly, brown, ring-necked, earthworm, and Southeastern crowned snake rarely get over 12 to 16" long. Medium sized snakes typically range from 18" to 3' in length. These might include garter snakes, ribbon snakes, green snakes, queen snake, milk snakes and kingsnakes. The large snakes can often obtain sizes in excess of 3' and would include rattlesnakes, rat snakes, watersnakes, coachwhips, black racers, and cottonmouths. Body Shape The next question to ask concerns body shape. "Is the body slender, or is it thick and heavy?" Examples of a slender snake would be the ribbon snake whereas an example of a stout snake might be a cottonmouth. Head & Neck Shape Next look at the head. Does it have a broad head? A medium sized head (a little larger than the body)? Or does it not appear to have a head? Many of the small land snakes do not appear to have any significant head whereas species like the garter snake have a medium sized head. Water snakes, cottonmouth, Eastern hog-nose, and rattlesnakes all have large heads. Folklore has it that if the snakes' head is shaped like an arrowhead it is venomous. While it is true that pit vipers (these are the only poisonous snakes in Kentucky) do have heads that might have an arrowhead shape, many nonvenomous species may flatten their heads into the arrowhead shape when they feel threatened. Therefore this is not a good characteristic to tell the difference between poisonous and non-poisonous snakes. Color & Pattern The most useful field identification characteristics to use in identifying snakes are their color and patterns. Some snakes like the rough green snake are easy to identify because they are the only bright green colored snakes that occur in Kentucky. Corn snakes are bright orange and scarlet snakes are bright red. Look at the color of the snake carefully. Is it really black or dark brown? Is it dark gray or brown? Patterns are also very helpful. For instance many snakes have no discernable pattern at all. The earth snake and black racer are good examples of snakes that are generally one color with no lines, blotches, or bands. Some snakes have a head that has a different color from the body. The southeastern crowned and ring-neck snakes are excellent examples of this type of pattern. The coachwhip is an example of a multicolor pattern where the color gradually blends from one to another with no distinctive pattern. The garter, ribbon, and queen snakes are examples of species that have linear stripes running the length of the body. The final pattern to look for is a snake that has spots, blotches, or bands. Species that may exhibit this type of pattern include the rattlesnakes, copperhead, corn snake, rat snake, milk snakes, water snakes, kingsnakes, pine snake, cottonmouth, and brown snake. Scale Texture If you are still having difficulty identifying the snake you may want to look at the scale texture, tail scales, and the anal plate division. Some snakes have scales that are rough (or have a ridge on them). Snakes that have no rough (keeled) scales are often quite shiny in appearance. As a general rule we do not have any snakes in Kentucky with strongly rough scales. Some species with mild keeled scales include the rat snake, corn snake, copperhead, and cottonmouth. Most of our snakes have smooth scales. Eye Pupil Shape An easy method of telling the difference between a venomous or poisonous versus a non-poisonous snake is to look at the shape of the pupil. Non-poisonous snakes all have a round pupil (in the center of the eye) whereas all poisonous snakes have a vertical elliptical (cat-like) shaped pupil. All pit-vipers (poisonous) also have a small hole (pit) between the nostril and the eye. Anal Plate Division The anal plate on a snake is the last body scale on the underside or belly. One good identification characteristic is to determine if the snakes' anal plate has one scale or is it divided into two scales. You can not use the anal plate to tell the difference between poisonous and non- poisonous snakes. You can use the tail scales to determine if a snake is poisonous. The pit vipers (poisonous) have a single row of scales under the tail beginning at the vent. Near the end of the tail, the single row will change into a double row. All others have single tail scales.