Identifying the glassy-winged sharpshooter
If you have an insect that you think is the glassy-winged sharpshooter (GWSS), you can use this page to help you identify the insect.
The GWSS adult, which reaches a half inch (13mm) in size, is relatively large for the sharpshooter/leafhopper family of insects. On the left is a good example of the sharpshooter’s profile. You can see the distinct orange underside of the head where the proboscis or mouthpiece is. It uses this mouthpiece to pierce the shoots and branches to draw in the fluids and get nutrients and minerals from the plants. The wings of the sharpshooter are translucent brown with red veins. The top of the insect is dark brown while the underside is white.
Nymphs of GWSS are the immature life stages before adulthood. The sharpshooter’s nymphs, like the one to the left, are greenish grey in color and quite similar in shape to the adults. The nymphs do not have wings and are generally smaller than the adults, ranging in size from .07 inches (2 mm) to nearly half an inch (13mm) long. The nymphs have very distinct red eyes that are visible when they are alive. The nymphs are much more active than the adults, and are more likely to jump away when approached.
The sharpshooter lays its eggs inside of the underside of leaves. GWSS will lay eggs on almost any plant, including cactus. To the left is a good example of a sharpshooter egg mass. The egg masses are on average composed of 10 - 20 eggs, although they can lay as few as one egg. Most of the egg masses have a waxy coating around the eggs for protection. The eggs are lined up, making a rectangular pattern of eggs on the leaf. The eggs are all in separate chambers so you can see the walls between each egg, which makes their egg masses distinctive. On the top of the leaf, there is usually some discoloration. To find the eggs, it is easiest to get under the tree or shrub and look up at the leaf with sunlight behind it. The egg blocks out some of the sunlight and you can see the distinct shape of the egg through the leaf.
When the nymphs hatch, they split the leaf open on one side. In time the area where the eggs were will start to turn brown, leaving an "egg scar" that remains until the leaf falls from the plant. Another way the egg mass can leave an egg scar is after parasitization. To the left is a picture of an egg scar left after the egg mass was parasitized. These scars are helpful to show where the GWSS has been. At times the scars have been brought in with the plants in new landscaping so as to give the appearance of a previous infestation. As with the fresh egg masses, you can find them in the same way by looking up from below the plant. The egg scars tend to stand out more than the fresh egg masses.
Additional helpful information
Each GWSS can consume about 300 times its own weight in fluids from the plants that it feeds upon, and they can be found in such high numbers that they cause what is called "sharpshooter rain". When a large number of GWSS are in a tree, they constantly draw fluids out of the branches and excrete them out the other end, which gives the appearance of rain coming off the tree. This excreta also causes the whitewashed appearance on leaves, fruit and even on the sidewalk under it. There are other ways to create this whitewashed appearance, such as minerals depositing from water. White spots on plants are not always a sign that sharpshooters are present, but if you see it, closer inspection may reveal GWSS hiding on the stems or branches of the plant.
A few of the sharpshooter’s favorite plants to feed on are bougainvillea, camellia, citrus, crape myrtle, grapevines, eucalyptus, privet, and oleander. While these are favored hosts, GWSS has been found to favor a large range of plants. The California Department of Food and Agriculture establishes a current list of plants that are regulated as hosts of GWSS.
Contact information if you suspect you have found GWSS
If you find any evidence of the sharpshooter, please notify staff at our Concord or Knightsen offices.
If it is possible, please drop off any samples that you suspect to be GWSS at our Concord or Knightsen offices. You can also call the California Department of Food and Agriculture hotline at 800-491-1899.