Spittlebugs: Generating More Curiosity Than Problems

by Christina Tyler Wenks, Fairfax Master Gardener

Pine Spittlebug

Pine Spittlebog

What appeared to be bits of foam scattered across a backyard was not uncollected trash hewn and strewn by mowers, but a dozen inch-round buggy bobbles firmly affixed to blades of grass. The green spring lawn speckled with spitballs, a far cry from those in elementary-school lunchrooms, led down a rabbit hole of hands-on investigation.

Spittlebugs are known for their frothy masses produced while piercing stems and feeding on the juices from ornamental grasses, roses, chrysanthemums, clover and herbs. Virginia is home to several spittlebug species. A few species are particularly fond of strawberry and can affect plant growth and annoy pickers. In the Mid-Atlantic region, scotch pine is a preferred host of the one of the species, but spittlebugs may also be found on pitch, Eastern white, Virginia, jack, slash, loblolly, Japanese and mugo pines.

Eggs are oviposited and overwinter in the stems of plants, often at or near the base of the plant, and emerge in April. Warm winter and spring weather can result in an earlier appearance. Wet springs can result in higher numbers.

spittlebug nymph

Twolined Spittlebug nymph in lawn

A puffy coat filled with many colors
As nymphs feed, a specialized air canal mixes their excretions to create a protective bubble wrap. Quarter-inch-long black, orange or yellow nymphs, some with red eyes, grow inside the 3/4-inch-diameter bubble masses that protect nymphs from desiccation and predators. One or more nymphs can mature inside a single spume.

After five to eight weeks, a few species of the adult spittlebugs move from leaf litter into grassy areas and pastures — particularly those with broadleaf weeds — where females return in fall to deposit eggs that will hatch the following spring.

In most cases, nymph and adult spittlebugs feeding on plants is not damaging to the plants. However an abundance of spittlebugs on a single plant or tree can cause some leaves to lose shape. A few species of spittlebugs may secrete a toxin that destroys plant tissue, causing leaf stunting, distortion and twig dieback.

adult spittlebug

Adult Twolined Spittlebug

Adult spittlebugs are often called froghoppers because they look like wide leafhoppers with long hind legs that allow them to jump. Adults are present from late spring to early fall. Some emerge green with two irregular, whitish bands on each wing before their leafy color turns to grey. Black spittlebugs may have two orange wing stripes. Meadow spittlebugs range from light brown to black.

Spittlebugs in the Mid-Atlantic region are not often found in large numbers and generate more curiosity and unwarranted concern for the gardener than harm. Nymphs protected by spittle are not affected by pesticides, so removing nymph spitballs from bases of plants by hand is recommended treatment. A blast from a water hose will dislodge the bugs from ornamentals and their spittle-sack shields, increasing the chances of the insects drying out or becoming prey.

meadow spittlebug

Adult Meadow Spittlebug

Control
Removing broadleaf weeds discourages some spittlebugs, too. Controlling lawn thatch is one control measure. Another is to avoid placing host plants that attract adults, such as Japanese holly, near lawn grasses. If treatment is necessary, mow and irrigate turf grass several hours before applying a pesticide treatment late in the day. Centipede grass is susceptible to spittlebugs. Zoysia, bermudagrass and bahiagrass are also hosts for spittlebugs because some species of the insect are associated with heavy thatch.

Heavy infestations of pine spittlebugs in successive years could threaten or kill a Scotch pine. In the case of a threatening infestation, cooperative extension agents recommend a contact insecticide on the foamy masses. Most spittlebugs produce one generation per year. A second generation appears to cause more injury. Populations, and therefore, damage, can be prominent during years with high spring and summer rainfall.