The pine spittlebugs, Aphrophora cribrata (pine spittlebug) and Aphrophora saratogensis (Saratoga spittlebug), feed on a variety of coniferous and other host plants. "Spittlebug" refers to the habit of the nymphs of these species, which produce frothy liquid around themselves to keep moist and protected from natural enemies.
The pine spittlebug, A. cribrata, is found throughout the eastern United States and parts of Canada. It can be a serious pest in pine plantations. In the host list above, it is noted which species A. cribrata can utilize. Adult females lay their eggs in the bark of twigs, even sometimes in dead wood. Eggs overwinter. In the spring, the nymphs hatch and begin feeding on host plant twigs. With piercing-sucking mouthparts, the nymphs feed on sap from host plant phloem. Sap is partially digested, whipped into a spittle-like foam, and several nymphs may be found in a single spittle mass. Adults will feed on host plant twigs in the mid-to-late summer, but do not produce spittle (rather, honeydew). In heavy populations, honeydew may be excreted as a fine mist on foliage and twigs below. On the honeydew, black sooty mold (a fungus feeding on the sugary insect waste) may grow. In the northernmost area of its geographic range, a single generation occurs per year. Slash pine (Pinus elliottii) is also a host of the pine spittlebug, but is found in the southeastern United States.
The Saratoga spittlebug, A. saratogensis, can cause economically significant damage on certain host plants. A single generation of this species also occurs per year. 2 mm long eggs are laid by adult females under loose bark scales, bud scales, or in needle sheaths of its host plants. Eggs are also the overwintering life stage for the Saratoga spittlebug. Nymphs hatch from these eggs and move to understory shrubs to feed. Hosts of the nymphs of the Saratoga spittlebug are differentiated from those of the adults in the host plants list above. Adults of this species feed on several species of pine. Two hosts are required for the successful completion of the Saratoga spittlebug life cycle. Adults are 0.4 inches long and tan/brown in color and active from late-June until the frost kills them at the end of the growing season. Adults feed with piercing-sucking mouthparts in young pine twigs. The removal of host plant fluids from this area causes necrotic, resin-filled pits to form. Peak adult feeding occurs over a two-week period near the end of July, beginning of August.
Heavy infestations of the pine spittlebug (A. cribrata) are capable of causing twig and branch mortality. On occasion, tree mortality may be possible. In 1927, 70% of Scotch pines in a plantation in what was then Logan State Forest in Pennsylvania were killed by the pine spittlebug. Saratoga spittlebug (A. saratogensis) adult feeding may lead to a reduction in terminal twig elongation, yellowing of the needles, twig mortality, and branch mortality. In high enough populations, host tree mortality is possible. However, at least 3 or more years of heavy feeding is necessary for the Saratoga spittlebug to kill a tree. Keep in mind that the Saratoga spittlebug is unlikely to occur on ornamental host trees in well-managed plantings.
Visually scan 1-year old shoots for feeding wounds and scars from spittlebug adults. Examine the bark of shoot tips from fall to spring to look for small elongated bumps indicating the presence of eggs. Slicing into these areas carefully with magnification may help confirm the presence of eggs. The easiest way to detect the presence of spittlebugs is to look for the globs of spittle from the feeding nymphs in the spring. These will be on the shoots and the trunk.
Removing the nymphal host plants of the Saratoga spittlebug (A. saratogensis) will eliminate the insect from a localized area as these secondary hosts are a requirement for the development of this species. Pruned trees, with dead and dying branches removed to destroy egg sites, may show less injury than unpruned trees (Wilson, 1991).
Entomophthora aphrophorae is an insect killing fungal pathogen of the pine spittlebug, A. cribata. This pathogen may occur in 9-year intervals, at which point spittlebug populations are reduced. Hirsutella spp. fungi are described killing spittlebugs in Florida. Other insects and spiders will feed on spittlebugs. Nymphs of the stink bug species Podisus serieventris are predators of pine spittlebugs. Nabis spp., Pselliopus cinctus, and Hoplisus atricornis, have all been observed feeding on pine spittlebugs. Mites have also historically been observed associated with them (Wilson, 1991).
Acephate (NL)
Azadirachtin (NL)
Bifenthrin (NL)
Carbaryl (L)
Chlorantraniliprole (NL)
Chlorpyrifos (N)
Cyantraniliprole (NL)
Cyfluthrin (NL)
Deltamethrin (L)
Gamma-cyhalothrin (L)
Lambda-cyhalothrin (L)
Malathion (L)
Neem oil (NL)
Pyrethrin+sulfur (NL)
Active ingredients that may be applied systemically include: acephate (injection), azadirachtin (injection, soil drench), chlorantraniliprole (soil drench), cyantraniliprole (soil drench, soil injection), and neem oil.
When used in a nursery setting, chlorpyrifos is for quarantine use only.
Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.
Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.
