Know more about it? This is known as spittle bug and motley found on weed plants in barren land. Sometimes, they also observed in our crop plants. These bugs emit one kind of bubbles (foam) and wrap around it. Thus it can get protection against high temperature and also from the predator/parasites. The bug, remain inside the foam, suck the sap from the plants. The damage due to these bugs observed if they are in high population. There is no need to take any action if observed one or two on plant