When we think “spittlebug,” images of the frothy masses produced by the Pine Spittlebug (Aphrophora cribrata) on various conifers, or the Meadow Spittlebug (Philaenus spumarius) on over 400 species of plants, may come to mind. However, I recently came across dogwoods growing along a trail in southwest Ohio that were festooned with the frothy, spittle-like masses produced by the Dogwood Spittlebug (Clastoptera proteus); a reminder that there are at least 23 different species of spittlebugs (family Aphrophoridae) in North America.
Spittlebug nymphs are responsible for producing the frothy masses; adults of these insects are called "froghoppers" and have an entirely different life style. The nymphs insert their piercing-sucking mouthparts into phloem vessels to extract amino acids dissolved in the sugary plant sap. The nymphs discharge excess sap from their anus and create their frothy mucilaginous masses by pumping air into the sugary, sticky liquid. Dave Shetlar (OSU Entomology) has long contended "anal bumble bugs" would be a more appropriate name for these insects.
The nymphs can be found embedded within their frothy mass with the foamy "spittle" serving several functions including protecting them from predators and parasitoids. Most types of spittlebugs cause little harm to their hosts and are primarily viewed as oddities. Dogwood spittlebug is a good example. While they may feed on all species of dogwoods in Ohio's woods and landscapes, their "damage" is mostly relegated to the unattractive appearance of the spittle-masse as well as the unsightly occurrence of blackened foliage produced by sooty molds colonizing spittle that drips onto leaves.