Prevention of wasps and yellow jackets. Slice a fresh cucumber into thin slices and arrange them in a single layer on an aluminum pie plate. The cucumber must be fresh – the pan must be aluminum. The cucumber reacts with the aluminum and gives off a chemical reaction/scent that is undetectable to humans but drives wasps and yellow-jackets away and makes them flee the area.
How to make a wasp, hornet or yellow jacket trap from a 2 liter bottle. To keep the bees from getting in here (and keep them doing their good job!) just add apple cider vinegar. Bees don't like the sour, but wasps do.