There are hundreds of species of leafhoppers that may feed on ornamental trees and shrubs. Adult females are difficult to identify to species. Some species are capable vectors of woody plant diseases. Many species of leafhopper overwinter as either eggs or adults. Overwintering eggs may be embedded in shoots, twigs, or stems by the female. In species where the adult overwinters, they shelter in the cracks and crevices of bark or beneath the leaf litter. If the species has multiple generations per year, another set of eggs may be laid in host plant leaf tissue in the petiole or veins during the growing season. Females will often select preferred host plants for egg laying. Feeding from nymphs (immature stage) and adults typically occurs on the underside of the host plant leaf, but will be visible as whitish stippling from the upper surface. Most species of pest leafhoppers are between 1/8 to 1/4 of an inch in length as adults. Adults are long, slender, with wings held rooflike over their backs when at rest. Leafhopper adults also have rows of spines on the longest segment of their hind legs. Nymphs are similar in appearance to the adults but typically smaller and with not fully formed wings called "wing buds". Late in the season, in many species, adult leafhoppers become polyphagous in their feeding (after initially remaining on the same host plant their egg was laid on and fed upon by the nymph). Many leafhoppers require high humidity environments for survival.
*Common species of leafhoppers discussed elsewhere in this guide include but are not limited to: the maple leafhopper (Alebra albostriella), potato leafhopper (Empoasca fabae), red banded leafhopper/sharpshooter (Graphocephala coccinea), rose leafhopper (Edwardsiana rosae), and the white banded elm leafhopper (Scaphoideus luteolus). Each is matched to their possible host plants listed above.
Many leafhopper species either feed in the mesophyll or in the vascular tissue (xylem and phloem). When feeding in the mesophyll, piercing-sucking mouthparts are inserted through the bottom of the leaf, through the mesophyll, and into cells called palisade cells which are fed upon. This type of feeding (in the mesophyll) results in yellowish/white stipple spots. These spots often coalesce into large, whitish blotches on mature leaves. On host plants where this occurs, the tree or shrub may respond to this feeding by showing reduced vigor or stunting (Johnson and Lyon, 1991).
Leafhopper species that feed in the vascular system (xylem and phloem) cause the leaves of host plants to curl or become distorted. Some of these species may have saliva that is toxic to the plant and capable of moving to leaf tissues adjacent to the original feeding site. In this case, leaf margins may become necrotic and turn brown, a symptom referred to as hopperburn (Johnson and Lyon, 1991).
Noticeable damage from leafhopper feeding may be more common in nursery settings than in managed landscapes. Adults and nymphs may be found feeding on the undersides of the leaves of most deciduous trees, shrubs, and flowering fruit trees. The damage caused depends upon the species of leafhopper involved, the host plant, and the size of the population of insects. For example, certain species may cause extensive feeding damage on young plants. Older, established plants may be more tolerant to their feeding. On occasion, leafhopper feeding damage may be mistaken for herbicide injury to host plants.
Monitoring for leafhopper activity can begin as soon as host plant leaves have opened in the spring. Check terminal leaves first, as some species prefer to begin their feeding in those locations. Coarse, whitish stippling may begin near leaf midribs. Some species may also be very attracted to yellow sticky traps, and thus that technique can be used to monitor for leafhopper activity. (If using yellow sticky traps in a nursery, check the cards at least once a week.) Scout plants and look for whitish stippling, yellowed or distorted and possibly scorched (hopperburned) foliage. In some species, honeydew and sooty mold may also be detected.
As always, promoting the overall health of the host plant will help reduce the impact of leafhopper feeding.
In nurseries, screening or covers can be used to exclude some leafhoppers from young, high-value plants. Certain species of leafhoppers may be found amongst weeds or other alternate hosts. Reducing the presence of weeds in the area may help to reduce or discourage their populations. In some studies, silver reflective plastic mulches have been shown to repel leafhoppers (ex. in corn crops) but this may be a useful tool in nursery production as well.
Natural enemies and biological control options will differ depending on the species. See entries for the maple leafhopper (Alebra albostriella), potato leafhopper (Empoasca fabae), red banded leafhopper/sharpshooter (Graphocephala coccinea), rose leafhopper (Edwardsiana rosae), and the white banded elm leafhopper (Scaphoideus luteolus) for specific information when available.
In general, for the particularly damaging leafhopper species that impact trees and shrubs, natural enemies rarely provide effective reduction or management of their populations.
Acephate (NL)
Acetamiprid (L)
Azadirachtin (NL)
Beauveria bassiana (NL)
Bifenthrin (NL)
Buprofezin (NL)
Carbaryl (L)
Chromobacterium subtsugae (NL)
Chlorpyrifos (N)
Clothianidin (NL)
Deltamethrin (L)
Dinotefuran (NL)
Fenpropathrin (NL)
Tau-fluvalinate (NL)
Gamma-cyhalothrin (L)
Imidacloprid (L)
Insecticidal soap (NL)
Isaria (paecilomyces) fumosoroseus (NL)
Lambda-cyhalothrin (L)
Malathion (L)
Neem oil (NL)
Permethrin (L)
Pyrethrins+piperonyl butoxide (L)
Pyrethrin+sulfur (NL)
When used in nursery settings, chlorpyrifos is for quarantine use only.
Active ingredients that may be applied systemically include: acephate (injection), acetamiprid (injection), azadirachtin (injection, soil drench), clothianidin (soil drench), dinotefuran (soil drench), 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.
