Question
tree foam
I have some trees in my back yard, which I think started out as a privacy hedge, but I've lived in my house for 2 years and today I noticed that there is large amounts of foam around the base of each tree. Up close it looks like foam from detergent or dish soap, it's white and very bubbly. I didn't touch it or smell it but I didn't notice any bugs around it. What could it be? Is it dangerous to any other plant in my yard? And will I have to remove the tree/shrubs?
AnswerIt looks like spittle bugs. These insect hide in the spittle. They can be found in the grass or on the stems of plants.
Although there are many different species of spittle bugs which often make them difficult to distinguish, these insects are best known for their unusual habit of forming masses of spittle. The spittle bug are from the Cercopidae family of insects in the order Homoptera which means same wing bugs. Of the four common species of this insect, two live in meadows while the other two live in pine trees. The species Philaenus spumarius is one of the meadow spittle bugs whose juveniles or nymphs are a brown color with spots and known to feed mostly on alfalfa and clover. The species Lepyronia quadrangularis is the second this species of the meadow spittle bugs. It can be identified by the two oblique bands across its back and its preference for feeding on grass.
It is believed that the spittle produced by the spittle bug may serve several functions. The substance provides a moist environment that keeps this vulnerable insect from drying out but it may also be used as a form of protection from predators providing a substance that is distasteful and unpleasant for the predator to search through. Although these insects can be found in both the adult and nymph stages they are more easily recognized in the nymph stage when they are creating spittle. When the spittle is pushed away the juvenile will be about one eighth inch long and a light green color. In the adult stage these insects are best found in lush grasses. They tend to make very large hops and are brown oval insects with stout appearing bodies. During their life the spittle bug will over winter as eggs laid on plant stems. During the spring the young hatch and immediately begin forming spittle masses for the excess plant juice they feed on.
These insects do little damage to their host. The spittle can be annoying, especially if it is present on twigs where persons and pets can get into it. In such locations, a forceful stream of water from a hose can be used to wash the spittle and the nymphs off the tree.
As long as the trees and shrubs are leafing out and are green they will be fine. The spittle bugs do very little damage to plants so I would not really worry about them. I would take a water hose and wash the spittle away.
