The purpose is to prevent insects, because only after the May Festival will all kinds of insects appear, tied to beams or placed on windowsills to prevent insects.
Worms hide when they meet mugwort. There is this superstition, but it is also Chinese medicine. People can use it to treat diseases. If they have rheumatism, they can use it to wash. First, boil it into water and wash it every day. The effect is very good.
You can use it to treat leg pain and joint pain. Can be used to boil, soak feet every day to get rid of dampness, and can also treat rheumatism.