The white-banded elm leafhopper is a phloem-feeding leafhopper and feeds only on the leaves and shoots of elm. While this species is normally not abundant, when present it feeds near the midrib and larger leaf veins of its host plant, on leaf undersides. Feeding by this leafhopper can cause the tips of host plant leaves to die, a symptom often referred to as "hopperburn". Nymphs of this species are able to disperse, along with the adults of the species, with the exception that adults have fully developed wings and can fly. Nymphs are light brown in color with a white band that crosses the insect behind the thorax. There are 5 nymphal instars. Adults can move between trees, and are found most frequently in the inner crown. The white-banded elm leafhopper's feeding alone causes little to no damage to its host. The ability of the leafhopper (along with other leafhoppers and potentially a spittlebug) to vector elm yellows is what is of most concern with regard to the overall health of the host plant (Johnson and Lyon, 1991). The phytoplasma that causes elm yellows incubates in the gut of the insect for 3 weeks and then moves to the insect's salivary glands. After that, the insect is able to transmit the phytoplasma to its host plants any remaining time that it spends feeding. Elm yellows is not known to pass from the insect's eggs into the adult. The white-banded elm leafhopper overwinters as an egg on the bark of its host plants. Eggs hatch when temperatures warm in the spring, right around bud break. The leafhoppers pass through nymphal (immature) life stages for approximately 5-6 weeks and develop into the adult stage by late summer. They may be present throughout the growing season until the first significant fall frost.
The white-banded elm leafhopper feeds on the undersides of elm leaves. This species vectors elm yellows, also known as elm phloem necrosis, in elms. Elm yellows is caused by phytoplasmas, which are bacteria-like plant pathogens. If it weren't for the ability to vector elm yellows, the feeding by the white-banded elm leafhopper would be of next to no significance. Elm yellows causes the leaves of the host plant to wilt, yellow, and drop prematurely from the tree by the summer. Roots are killed by the disease, and the tree can die in 1-2 years. The inner bark (phloem) and most of the xylem, which conducts water in the tree, turn yellow or butterscotch in color. It takes 3-6 months for symptoms of the disease to become apparent, post inoculation. Yellowing and browning of the host plant may not appear until the following season. Currently, no effective management option exists for the disease, and once a tree has elm yellows, removal and destruction of the tree is recommended.
Monitor for foliar decline in susceptible elms, such as leaf drooping, curling upward at the margins, and turning yellow-green, bright yellow, and then brown before dropping from the plant. This typically takes place between mid-July and mid-September. Once the disease is present in the tree, the only management is tree removal. The insects themselves and their life stages may be difficult to visually monitor on the host plant, especially given that they typically do not occur in large populations.
Asian and European species of elms (such as: Ulmus carpinifolia, U. glabra, U. laevis, U. parvifolia, and U. pumila) appear to be highly resistant to elm yellows, and can be planted alternatively to American or native species of elm in areas where elm yellows is an issue. Keep in mind, however, that Dutch elm disease (DED; caused by Ophiostoma novo-ulmi and O. ulmi) can cause damage to European elms. Eurasian elms can still become infected with elm yellows, and in some cases may grow slowly as a result or develop witches' brooms. ‘Frontier,’ ‘Pathfinder,’ and ‘Patriot’ hybrid elms appear to tolerate elm yellows, and “Homestead” hybrid elm appears to be resistant to elm yellows. The best management practice for elm yellows in North America is choosing to plant resistant species or hybrids (Walla and Koch, 2016; US Forest Service, Rocky Mountain Research Station, General Technical Report).
Natural enemies of the white-banded elm leafhopper are not well discussed in the literature concerning this insect as a vector of elm yellows.
Acephate (NL)
Acetamiprid (L)
Azadirachtin (NL)
Beauveria bassiana (NL)
Bifenthrin (NL)
Buprofezin (NL)
Carbaryl (L)
Chromobacterium subtsugae (NL)
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)
While chemical management options for managing leafhoppers do exist, there are conflicting arguments for or against managing the white-banded elm leafhopper to prevent the spread of elm yellows in the available research. Suppressing the insects that vector elm yellows may be impractical, and many do not recommend chemical management of this insect.
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.
