Iowa
Snakes in Johnson County
17 species have been documented here, 3 of them venomous.
Venomous snakes in Johnson County
Full guide & what to do if bitten →
Timber RattlesnakeCrotalus horridusVenomousHeavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
Prairie RattlesnakeCrotalus viridisVenomousHeavy body, broad triangular head, vertical (cat-like) pupils, and a segmented keratin rattle at the tail tip.
Eastern MassasaugaSistrurus catenatusVenomousStout, dark-blotched body, nine large scales on the crown, and a small rattle.
Every snake recorded in Johnson County
Common Garter Snake
Thamnophis sirtalis
Harmless
DeKay's Brownsnake
Storeria dekayi
Harmless
Western Foxsnake
Pantherophis ramspotti
Harmless
Common Watersnake
Nerodia sipedon
Harmless
Plains Garter Snake
Thamnophis radix
Harmless
Eastern Milksnake
Lampropeltis triangulum
Harmless
Gopher Snake
Pituophis catenifer
Harmless
North American Racer
Coluber constrictor
Harmless
Smooth Greensnake
Opheodrys vernalis
Harmless
Eastern Hognose Snake
Heterodon platirhinos
Harmless
Timber Rattlesnake
Crotalus horridus
Venomous
Eastern Foxsnake
Pantherophis vulpinus
Harmless
Ring-necked Snake
Diadophis punctatus
Harmless
Western Ribbon Snake
Thamnophis proximus
Harmless
Prairie Rattlesnake
Crotalus viridis
Venomous
Eastern Massasauga
Sistrurus catenatus
Venomous
Graham's Crawfish Snake
Regina grahamii
Harmless
Compiled from verified GBIF & iNaturalist observations. Informational only.