Who's Spittin' on My Dogwoods?

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During today's weekly BYGL Inservice, Amanda Bennett (OSU Extension, Miami County) shared some striking images of the frothy, spittle-like masses produced by dogwood spittlebug (Clastoptera proteus) on its namesake host.  Spittlebug (family Cercopidae) nymphs are responsible for producing the frothy masses; adults of these insects are called "froghoppers" and have an entirely different life style. 

Dogwood Spittlebug Nymph
Dogwood Spittlebug Nymph

Spittlebug 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 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.

Dogwood Spittlebug
Dogwood Spittlebug Mass

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.