I personally don't think you need pepper spray to deter dogs anywhere in the continental US. On my tour I carried bear spray, but then again the only place I needed it for was the Stewart Cassiar highway in British Columbia. I saw nineteen bears there, but never had to use it once. Then again, I'd rather be safe than sorry. The only place you might need any kind of spray against dogs is a place like Mexico, where there is a ****load of stray dogs. I didn't carry any while I was there either. I'd usually just speed up, or try to kick the dog. I think a better option to fend dogs away is to simply carry a stick and wack them.