I saw this cool idea from keeping ants and other insects away from your picnic party. You would do this at home or at the cabin. Put four bowls of water, one under each table leg. what insect would climb into the water for a bath? None, that I know of.
Another idea was to sprinkle talcum powder around the grass where you are having a picnic. I don’t know if I would do that with your children crawling around. I have some questions about talcum powder being even sprinkled on a babies bottom.