These things are hard to avoid. You never know you are in them until it's too late. I do have a good home remedy for the sting. Are you familiar with a weedy plant called broad leaf plantain? It is also called dock by locals. It's a low growing plant you probably have in your yard. Below is a link that gives a photo.

http://www.eattheweeds.com/white-mans-little-foot-dwarf-plantain-2/

This is a great remedy for bee and wasp stings. I've used it several times on myself and kids. To use it, dig the plant. The part you want is the crown. That is the bulb between the leaves and roots. Cut away the leaves and roots, then mash the crown. You want to mash it up so the juices will be released. Hold the mashed up crown firmly against the sting for 60 seconds. Press fairly hard. The plant's juice will be drawn into the sting and give immediate relief. I've had the pain go completely away in a couple of minutes, and at the least, the pain will be significantly diminished. This is a very useful plant.