FAQ
Why is Glassy-Winged Sharpshooter a threat?
The Glassy-Winged Sharpshooter damages a variety of plants and spreads lethal diseases to crops such as almonds and grapes for which there are no known cures.

It also dehydrates plants it feeds on, draining life-giving fluids from plants and trees such as oak, hydrangeas, citrus, dogwood, apples, eucalyptus and snapdragons and many more.

Scientists do not know the extent of damage caused by this water loss. But we do know that a citrus grove infested by Glassy-Winged Sharpshooters needed a 25% increase in irrigation to keep the trees healthy and productive! An adult Sharpshooter can extract plant fluid equal to 200 to 300 times its body weight in a single day. This is the equivalent of an adult human drinking about 4,300 gallons of water per day!

After the insect drains water from the plant, it excretes a liquid called "Sharpshooter rain" that leaves a white stain on anything outdoors, like plants, cars, sidewalks, and patio furniture.


Isn't this just a winery issue?
No. We are just starting to learn about this insect, but now we know that Pierce's disease, the lethal disease that attacks grape vines, is just one of the diseases that Glassy-Winged Sharpshooters spread from plant to plant.
What other problems do Glassy-Winged Sharpshooters cause for plants?
The insect also spreads a disease that attacks other crops such as almonds, citrus and alfalfa.

Besides spreading these diseases, the Glassy-Winged Sharpshooter also drains water out of plants it feeds on, including trees such as eucalyptus, sycamore and oak. Scientists are concerned about oak trees in California that are already under threat from Sudden Oak Death Syndrome. This loss of water could damage these beautiful trees even further.

Aren't there other insects that spread Pierce's disease?
Yes. For example, the Blue-Green Sharpshooter spreads Pierce's disease. However, it can only feed on the soft external parts of plants in areas that can be pruned off each year, so it is not extremely effective in spreading disease. But the Glassy-Winged Sharpshooter has a stylus, like a little drill, that can bore into woody parts of plants where the disease cannot be pruned away, and that's why it spreads lethal plant diseases so rapidly.
What would happen to our economy if our Counties were infested with the Glassy-Winged Sharpshooter?
Because this insect could wipe out crops such as grapes, almonds, citrus, apples or alfalfa, our economy could really be devastated. Not only do these crops provide us with food, they also draw millions of tourists. It's not possible to estimate the number of people who could lose their jobs - from vineyard workers to landscapers and wait staff at restaurants and hotels and bed and breakfast establishments.

The price of land is so high in this area that grapes are one of the only crops that can be grown on the land, and still pay for itself. If our vineyards disappear, we may see massive development instead, because that may be the only other thing that could pay for the land.
What can we do to help right now?
Prevention is our top priority right now. You can help by buying plants at local nurseries, retailers and landscapers that are complying with the County's inspection program. Look for their Certificate of Compliance from the County Agricultural Commissioner that indicates that they offer plants that have been inspected for the Glassy-Winged Sharpshooter.

This will help us keep the Glassy-Winged Sharpshooter out of our Counties for as long as possible. If we do everything we can now, it may be possible to hold off the insect until we have an organic treatment developed that can effectively get rid of the Glassy-Winged Sharpshooter.

The insect has already infested many Counties in California, and many of the plants, trees and flowers that are imported into our County come from these areas. The State of California has implemented a strict inspection program for all the plants produced in these counties.

If you have friends or relatives that are visiting from an infested area in California, please let them know about our work to keep the insect out of our counties, and ask them not to bring any plant material to our area.
What are our Counties doing to stop the spread of the Glassy-Winged Sharpshooter?
The counties of Napa, Sonoma, Solano, and Marin are trying to do everything they can to prevent an infestation from occurring. In conjunction with participating retailers, nurseries and landscapers, inspection of incoming plant material is underway to stop the insect from being transported into our counties on plant shipments. Look for a Certificate of Compliance at your local store that indicates that their plants have been inspected for the Glassy-Winged Sharpshooter.

The Counties are putting traps out everywhere they can. These traps, made of sticky yellow cardboard, can be put in your yard if you're willing to help. Please call 1-866-BUG-SPOT if you're willing to have a trap in your yard.

The Counties have inspectors that are working very hard to do everything they can to help keep our counties lush and beautiful. But they cannot do it alone.

Please help by looking for any evidence of a Glassy-Winged Sharpshooter. And tell your friends and family and neighbors about the insect and what they can do to help stop its movement. And if you have time to volunteer to help let people know about it, please call 1-866-BUG-SPOT.

Since this insect has infested Southern California, why can't we stop plant shipments from there?
When the State of California issued their emergency orders last year to control the spread of the Glassy-Winged Sharpshooter, they required every county to submit a work plan to control the insect. Napa County did submit a work plan that sought to stop plant shipments from Southern California. The California Department of Food and Agriculture did not accept the work plan because it was considered to be harmful to free trade, so other plans had to be developed.
How long will this work of prevention and early detection last?
The research that is underway now is promising, but we still do not have a cure for the diseases that the Glassy-Winged Sharpshooter transmits, and we have no effective organic treatments as of today.

We hope that a solution will be found within five to ten years. If we can successfully keep this insect out of our counties for that time, we will prevent the extensive damage it could inflict.

What can we do if Glassy-Winged Sharpshooters do come into our counties?
During inspection of incoming plant shipments, we have already found egg masses of Glassy-Winged Sharpshooters. Because we found them at this stage we were able to just destroy the infested foliage and ship the plants back immediately. Click for a list of recent Glassy-Winged Sharpshooter finds

Early detection of the Glassy-Winged Sharpshooter gives us more treatment and control options. For example, if we just find an egg mass on one plant in a backyard, we may just be able to remove the egg mass or tear the plant , and save the rest of the vegetation in the area.

Since early detection is important, where should we look for these insects?
The important thing is to take a walk! Carefully look around your yard, your neighborhood park, and your garden. Encourage your neighbors and friends to do the same thing. Look for egg masses, nymphs or adults. The insect usually lays its eggs on the underside of leaves, but nymphs and adults could be anywhere, so look carefully!

Glassy-winged sharpshooters excrete a white liquid called "Sharpshooter Rain," so keep your eyes open for white stains your car, plants, flowers, sidewalks or patio furniture.

If you find evidence of white stains that may be Sharpshooter Rain or actual insects, please call us at 1-866-BUG-SPOT. When you call, we'll want to know where you found it, what it looks like, and something about the plant you found it on. Try to collect the evidence in a plastic bag, film canister, jar or a food container so we can make the proper identification. We've found that it helps to collect them in the early morning or late evening when the temperature is lower - they don't tend to fly away as quickly.

The list of plants that Glassy-Winged Sharpshooters feed on is growing every day as we learn more about the insect. Please visit the list of host plants for an updated list of plants that serve as a food source for the Glassy-Winged Sharpshooter.
After I find a Glassy-Winged Sharpshooter in my yard and call you, what happens?
If we think it may be a Glassy-Winged Sharpshooter, you can bring it in to the County Agricultural Commissioner's office, or we will come pick it up.

If you give us permission, we will check your back yard for other evidence of infestation. If we do find infested vegetation, we'll explain the steps you may be able to take, and what we will need to do to stop it from spreading to other areas.
Will a county inspector ever come to my door and ask to inspect my property?
Quite possibly. This is what the counties call the "Survey" phase of their action plans. If an inspector does come to your door, ask them for proper identification. You can then choose to give them permission to look in your back yard for Glassy-Winged Sharpshooters. We encourage you to allow your property to be inspected - it's an easy step you can take to help keep your county beautiful. You'll also have an opportunity to ask questions and learn more about how you can inspect your yard in the future.

Under the current action plan, an inspector may take a look around your front yard if you are not home, but will not go further onto your property. If an inspector does look at your property, he or she will leave a flyer on your doorstep and let you know they were there.
Will we need aerial spraying of pesticides in our Counties?
No. If pesticides have to be used at some point, it would only be applied to the actual infested location on the ground. We want to do everything we can to prevent anything like that from happening. That's why we need your help. If we can find the insects before they establish a large population, we have a good chance of stopping the spread of the insect without resorting to the use of spraying.
If our County did become infested, who is the final decision maker about whether or not we have to use localized pesticide spraying?
In July 2000 the State of California issued an emergency order that gave them the power to do what they think is necessary to control the spread of the Glassy-Winged Sharpshooter. They have allowed Counties to submit work plans that the State believes adequately provide for this effort. But if the Counties are unsuccessful in their own efforts to stop the spread of the insect, the State of California does have the right to come in and do whatever they think is necessary.
Are there biological controls for the problem at this time?
While research is intensifying and our hope is that positive outcomes will result, at this point in time there are no effective biological controls. Scientists are looking at using a wasp that feeds on Glassy-Winged Sharpshooter egg masses as a possible control, but these wasps would only be effective if there was a huge infestation. Otherwise, they would run out of food and simply leave the area.

You may also have heard about a kaolin clay repellent. This substance, if put on your plants, would keep Glassy-Winged Sharpshooters out of your yard, but they could always hop over the fence to your neighbors.

One very simple, non-chemical option for getting rid of the pest in small numbers, may be removal by mechanical means, or simply put, pulling out the infested plants. It may even be effective to vacuum them! The Agricultural Commissioner will determine what control methods are the most effective on a case-by-case basis.
Where did this insect come from?
The insect originates from South America, but it came here most recently through the Southeast portion of the United States of America. In Florida, the insect is responsible for the lack of a stone-fruit and grape industry.