Potato Leafhopper
Potato leaf hoppers are small insects that are easily overlooked until the damage called “hopperburn” starts showing up on plant leaves. They can affect a wide range of fruit crops, including apple, pear, grape, raspberry and strawberry, as well as many vegetable and field crops.
| Common Name | Potato leafhopper |
| Order | Hemiptera |
| Family | Cicadellidae |
| Scientific Name | Empoasca fabae (Harris) |
Identification and Life Cycle
Potato leafhoppers cannot withstand Wisconsin winters, and overwinter in the southern gulf coast states. The adults are blown up on wind currents into Wisconsin in May and June; however, this species is highly polyphagous (feeds on many different types of plant), and so often doesn’t show up in apple until immediately after the first cutting of hay in the area – usually around mid-June. Potato leafhopper adults are wedge-shaped and about 1/10 inch long. They are similar in appearance to the white apple leafhopper (Typhlocyba pomaria, McAtee), but have a more greenish coloration to the body. Both the adult and nymph potato leafhoppers move in a crab-like sideways manner, which is another distinguishing characteristic of this species.
The potato leafhopper eggs are laid in the upper canopy of the tree, generally on young leaves or stems. The nymphs are smaller than the adults, orange/yellow-colored, and lack wings, although the later instars (stages) have wingpads. From egg to adulthood typically takes around 25 days, and there are generally two to three overlapping generations of potato leafhopper in Wisconsin.
Damage Symptoms
Leafhoppers are most likely to affect young pre-bearing trees. They feed on the underside of foliage using a piercing/sucking mouthpart, and inject a toxin into the plant’s vasculature which slows water and nutrient movement. This can cause characteristic “hopperburn”, in which the edges of the leaves of an apple tree or other affected crop yellow and roll upwards. Hopperburn damage can resemble aphid damage, so it is important to look on the underside of the leaf to find either the leafhopper or aphid culprits. Additionally, potato leafhopper feeding damage has been shown to increase the prevalence of fire blight in an orchard, although the specific relationship between potato leafhopper and fire blight has still not been completely determined.
Monitoring and Control
Monitoring for curled leaves or shoots that are not growing vigorously can take place weekly beginning in June. If leafhopper damage is suspected, turn over the leaf slowly to be able to identify and count the leafhoppers on the bottom side of the leaf. No specific economic threshold has been determined as of yet in apple orchards, but it has been noted that one to two leafhoppers per shoot can cause curling damage. In an orchard with a history of fire blight, control is recommended when a single potato leafhopper is identified in the orchard.
Cultural control: Ideally, it would be best to avoid planning apple orchards near hay fields, as those can be breeding grounds for an influx of potato leafhoppers. Of course, that is often not possible to achieve, in which case it may simply be helpful to be aware of when hay is cut to be sure to begin a frequent potato leafhopper scouting program at that time.
Chemical control: A list of available insecticides to control potato leafhopper in apple is provided in the following table. For other affected fruit crops, be sure to read the label to make sure they are registered for that specific crop in Wisconsin. There are many other tradenames available, and we do not recommend these that are listed above other options. All product recommendations can be found in the Midwest Fruit Pest Management Guide. Additionally, you should always fully read and follow the label before spraying any pesticide.
