Any one know what to spray into a wall cavity (between studs behind drywall) to make a snake come out and not have to cut out drywall?

If you find something effective and non toxic I hope you will tell us all what it is.

If we scope the wall void and confirm it is in there we can incision the wall for a removal if it stays that long and if that is what the customer would like us to do. We do a good patch job but they have to get it finished to grade.

Temperature is probably your best friend. Snakes like to stay warm and don't do very well in a cold area. Even cranking the AC hopefully can get snakes moving .

Just as Bob Jameson said sometimes you have no options but cut them out. The nightmare is cutting into an area and then not get the snake. Its not hard to find a snake hiding behind the walls with the technology available to us today.

Frank Here are a few ramblings on snake trapping in general . Hope you can make sense of it !!

I have had success by first finding them with a inspection gun put out by Milwaukee - Infared Laser Temp-Gun and then applying dry ice wrapped in a blanket along the wall with the snake behind it and and glue boards in 8" PVC pipe with heating pad or zippo hand warmer at the end.

Snakes do not crawl backwards and in a tunnel or pipe require room enough to turn around which puts them on the roof of the tube at some point. A few strategic thin 1" double sided strips well placed in the top middle usually work when trapping using PVC pipe. Snakes prefer live bait to prepared baits . Snakes prefer food that gives off its own heat source

I have used bursts of pneumatic air to get snakes out of pocket doors and onto glue boards. If you do it right it makes for a pretty angry snake .

I use several mouse sized glue boards cut into 1" strips staple mounted onto paint stirrer strips (free at Home depot and Lowes) and do zone coverage of where I expect them to re-crawl and exit with some space between them . A bait mouse in the store's own container in middle of the glue boards. The problem with baiting snakes in general is you really need to know their diets and the type of snake you are trying to trap. Not every snake out there eats mice and rats so you need to learn your native snakes and their diet habits.

I have never killed a snake using glue boards . Snakes can easily be removed from any glue board without any harm. When you are setting traps for snakes just remember when you are snake trapping its a live set and needs to be checked just like a raccoon in or squirrel in a cage.

There are many snake phobic people out there that do not make good customers. Snakes bring out a lot of fear and sometime the snake is long gone and you can't get a snake that no longer in the area.

Great Source For Snake ID https://plus.google.com/109708747270584697786/posts/5jojdyjtV8g

Need a quick answer to a possible snake identification quick this is where we go.
http://www.oplin.org/snake/

If the homeowner will agree, naphthalene sprayed into the wall cavity will get them moving. A trap close by baited with a live caged mouse may also work for most snakes.

Can't imagine ANY homeowner being happy to have HIGHLY FLAMABLE chemicals sprayed inside their walls.