TULSA, Oklahoma - If you’re doing any spring cleaning in the garage or outdoors this season, you may find some unwanted guests in the form of snakes.

In most cases they avoid humans, but in case you do come across one, there are some ways to tell if they are venomous or not.

Spotting a snake slithering by is easy, but figuring out just how harmful it is might take a second look, according to Amy Morris with the Oxley Nature Center.

"If you were to get a close look at their eyes, venomous snakes have a vertical slit whereas non-venomous snakes have a round pupil."

Morris said there are exceptions to snake characteristics, but most often, most venomous snakes will have a triangle or viper shaped heads. Non-venomous snakes have round heads.

Tall grass and logs are common hiding spots for snakes, and, experts say, if you're walking through tall grass it's important to take a stick and shoo it in front of you to scare snakes away. And, if you come across a log, instead of stepping over it, stand on it first and that could also scare them off.

"If they get startled by you, unless you keep approaching them and try to threaten them, they will try and move away from you," Morris said.

If you're bitten by a venomous snake pain will be almost immediate, but the venom could take an hour or longer to take effect.

Experts say the best thing to do if you’ve been bitten by a venomous snake is to get to the hospital, otherwise the bite could cause infection, loss of limbs or death.