The tuliptree aphid is a native North American insect that occurs wherever the tuliptree grows. The overwintering life stage is the egg, hidden in cracks and crevices of host plant bark. Egg hatch occurs when spring temperatures allow, typically at budbreak. Depending upon local temperatures, these aphids may be present from mid-June through early fall. In Illinois, for example, tuliptree aphids are found from mid-June through most of October. The parthenogenetic, unmated females that mature from the overwintering eggs are able to give birth to live nymphs. Large populations can develop by late summer. Wingless adults are approximately 1/8 inch in length, oval, and can range in color from pale green to yellow and sometimes pinkish. Winged tuliptree aphids have translucent wings held rooflike over the body when at rest. The winged insects are greenish in color of the abdomen with reddish/brown heads and thoraxes. During the summer, females give birth to green colored nymphs that grow in size with each molt/shedding of the exoskeleton. The sexual (winged) form of this aphid is present near the fall and mates. There are several generations per year. The aphids are found feeding on host plant leaf undersides (Johnson and Lyon, 1991). The tuliptree aphid is an example of a native North American insect that has been introduced invasively into other parts of the world, including Slovakia in 2014 and 2015 (Kollár, and Barta, 2016) and previous introductions in Europe and Asia (Bozsik, 2012).
The tuliptree aphid can cause reduced leaf size as a result of its feeding. These insects feed on their host plants with piercing-sucking mouthparts which they use to remove host plant fluids. Some leaves, especially those in the outer canopy, may turn brown or yellow and drop from infested trees prematurely. The most significant impact these aphids can have is typically the resulting honeydew, or sugary liquid excrement, which may be present in excessive amounts and coat leaves and branches, leading to sooty mold growth. This honeydew may also make a mess of anything beneath the tree, including sidewalks and parked cars. Ants, bees, wasps, and flies may be attracted to and feed on the honeydew. Management is typically not necessary, as this insect does not significantly impact the overall health of its host.
Visually monitor for the presence of tuliptree aphids from budbreak to mid-June through the fall. They may be most noticeable by June. Flip over leaves to observe clusters of aphids on the host plant leaf undersides. Search the leaves at the tips of branches first, or any that are coated with honeydew (which appears shiny) or black sooty mold.
Syringing aphids (spraying the infested leaves with a strong stream of water from a hose) has often been suggested as a cultural/mechanical management option for these soft-bodied insect pests. This may help reduce their population without the use of insecticides, which could have negative impacts on the natural enemies that often suppress tuliptree aphid populations naturally. Proper planting, site selection, and tree maintenance also help reduce additional host plant stress which can be beneficial when managing insect pests of trees and shrubs.
Tuliptree aphids have plenty of natural enemies, such as ladybeetles and other predators, as well as parasitoids. Typically it is thought that the natural enemy populations can manage tuliptree aphids to the extent that the overall health of the host plant is not severely impacted. Thus, chemical management is often unnecessary; if chemical management options are employed, select reduced risk options to conserve natural enemy populations. Natural enemies of tuliptree aphids can be seen by flipping infested host plant leaves over. Search for aphid mummies (white or brown aphids that have been parasitized), lady beetle eggs (often yellow and laid in clusters), larvae, or adults, and other predators such as lacewings. Aphidius polygonaphis is a parasitoid wasp of the tuliptree aphid that is known to the eastern United States. It has been introduced into California as a biological control of the tuliptree aphid (Zuparko and Dahlsten, 1993). In Northern California, at least 12 primary and 14 hyper-parasitoid species have been identified of the tuliptree aphid (Zuparko and Dahlsten, 1993).
Abamectin (NL)
Acephate (NL)
Acetamiprid (L)
Azadirachtin (eggs) (NL)
Beauveria bassiana (NL)
Bifenthrin (NL)
Chlorantraniliprole (NL)
Chlorpyrifos (N)
Chromobacterium subtsugae (NL)
Clothianidin (NL)
Cyantraniliprole (NL)
Cyfluthrin (NL)
Cypermethrin (NL)
Dinotefuran (NL)
Emamectin benzoate (L)
Fenpropathrin (NL)
Flonicamid+cyclaniliprole (N)
Tau-fluvalinate (NL)
Gamma-cyhalothrin (L)
Horticultural oil (L)
Imidacloprid (L)
Insecticidal soap (NL)
Isaria (paecilomyces) fumosoroseus (NL)
Lambda-cyhalothrin (L)
Malathion (L)
Neem oil (NL)
Permethrin (L)
Pymetrozine (NL)
Pyrethrins+piperonyl butoxide (L)
Pyrethrin+sulfur (NL)
Pyriproxyfen (L)
Spinetoram+sulfoxaflor (N)
Active ingredients that may be applied systemically include: Abamectin (injection), acephate (injection), acetamiprid (injection), azadirachtin (eggs) (injection, soil drench), chlorantraniliprole (soil drench), clothianidin (soil drench), cyantraniliprole (soil drench, soil injection), dinotefuran (soil drench), emamectin benzoate (injection), imidacloprid (soil drench), and neem oil (soil drench).
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.
