Spittlebugs

Who’s Been Spitting on My Plants?

Have you seen frothy white spit-like masses on your plants this spring? The aptly named spittlebug makes these deposits after creating a spittle-like secretion by combining air with excess fluid secretions from the sap they consume. Notably, however, it isn’t really spittle—it comes out the other end of the body.

Spittlebugs are true bugs in the order of Hemiptera, with more than fifty species in North America. The most common in the Midwest is the meadow spittlebug (Philaenus spumarius). They are small insects, only ¼ to ½ inch long as adults, dull colored, oval, and hard to spot. More noticeable are the nymphs that are even smaller than the adults and are green in color. One might never see them except for the frothy mass in which they live. They produce the bubbles, sometimes as fast at 80 per minute, pull them up over their back with their hind legs, and go merrily on their way. The large-eyed nymphs hide out in this bubbly mass to escape predators, to insulate themselves against temperature extremes, and to keep their soft bodies from drying out as they go through two to four molts before adulthood.

If you are interested, brush away the spit and take a look. There may be numerous nymphs hiding out in a glob of foam. The nymphs are not accustomed to being exposed and will try to walk away, but they cannot fly, bite, or harm you. It is always fascinated to take a closer look at what is happening in your garden and landscape.

Spittlebugs overwinter as eggs in plant stems. The eggs hatch in early spring and the nymphs begin to feed and mature over 5-8 weeks. Both the adults and nymphs are sap-sucking creatures. Adults continue to feed throughout the summer, with only one generation per year. The adults are rarely noticed, but look somewhat like a small, fat tan and gray leafhopper. They have larger back legs for hopping long distances, giving them their alternate name of froghoppers. They will lay their eggs in early fall in plant debris, and the life cycle repeats.

These insects are often found on legumes because these plants provide a specific amino acid required for development. However, spittlebugs may also be found on meadow grasses, strawberries, clover, roses, goldenrod, chrysanthemum, Shasta daisies, coneflower, and a variety of garden plants. The good news is that they seldom require control as they do little damage to ornamental plants. If the appearance of spit on plants is unappealing or if the thought of grabbing a glob of it as you pick berries does not thrill, is can easily be dislodged with a strong stream of water. This will not eliminate the insect as it will simply crawl to another location and continue its life cycle.

There is a species of spittlebug that can cause damage: Pine spittlebug (Aphrophora parallella). They favor Scotch, Australia and white pine as well as fir, pines, and spruces. In this case the spittle will be noticed on the terminal twigs of the effected trees. Infestations over multiple years can cause damage and should be treated with appropriate insecticides.

Carol Shirk

Certified Master Gardener