Show All Answers

1. What’s that thing hanging in my tree/lawn/garden?

We use several types of detection traps, including the glass McPhail, paper Jackson, plastic Japanese Beetle, sticky paper panel traps and sticky delta traps. Most of the traps are specifically designed to attract a particular type of insect.

2. How was my house selected?

We noticed and admired your fruit tree(s) while we were working in your neighborhood. If you have a Japanese Beetle or Gypsy Moth trap, it was placed because your ornamental trees, turf, or roses caught our eye.

3. What if I don’t want a trap placed in my yard?

Please contact us by email or call us at (925) 608-6600.

4. How long will the trap be here? Will you place traps on my property every year?

We typically leave these traps on the property for six weeks or until the fruit is gone. The Japanese beetle trap and the gypsy moth trap are normally placed in May and removed in September. We try not to visit the same property until a full year has elapsed.

5. Will the person who places the trap go into my fenced yard?

The majority of the traps are placed in front yard fruit trees or on trees that hang over a public walkway. We do not enter backyards without leaving a notice in advance or talking to a resident of the property beforehand. If you received a notice but were unable to speak to a Pest Detection Specialist about a trap being placed, please call us with any concerns or special instructions about entering your property.

6. Do Pest Detection Specialists wear uniforms while placing and servicing traps?

No, but staff members will be carrying official identification and will be in a marked county vehicle.

7. Will I be charged for the trapping on my property?

Good news! We do not charge for this service. Trapping benefits our agricultural community and all residents with fruit trees and gardens that contain hosts of exotic fruit flies and other pests. Thank you for allowing us the use of your trees/turf/gardens to assist in the early detection of new pests.

8. Do I have to do anything with the trap?

Not at all. The trap will function best if you leave it alone. We will service the trap regularly. If you must move the trap, please do not throw it away. Instead, please leave it where we can find and retrieve it.

9. When will the traps be checked?

Some traps are checked weekly, while others are checked bi-weekly. The particular day may change due to holidays or other interruptions of the work schedule.

10. What happens if you find a target insect?

It depends on which pest, how many are found, and whether it is a male, unmated female, or mated female. A detection will prompt the California Department of Food and Agriculture (CDFA) to place more traps in the area to determine the extent of the infestation. In rare situations, state or county staff might need to take all the fruit off the tree and do some localized pesticide treatments. If this is the case, residents will be informed before their property is treated. If conditions warrant it, a quarantine restricting the movement of the host fruits, vegetables, or plants may be instituted. If this were to happen, CDFA and our department would hold public meetings to explain where the quarantine was located and how it worked in greater detail.

11. Will the traps attract other insects?

The glass McPhail traps, which contain water with yeast, attract any kind of fly that is in the area, including house flies. The yellow sticky panel trap is also a general trap and may catch non-target insects. The other traps we use contain a specific pheromone that only attracts the male of the target species. From time to time, other insects will wander into the traps and get caught.

12. Do the traps affect the fruit?

No, the traps do not affect the quality or safety of the fruit. In fact, they may actually protect the fruit from being destroyed by an insect pest. Pick, wash and enjoy your fruit as you normally do.

13. What should I do if I find your trap on the ground? Is it dangerous?

Since McPhail traps are made of glass, they can break. If you find a trap that has fallen to the ground and is broken, please carefully pick up and dispose of the glass in the regular trash as you would with other broken glass. The fluid inside might have a strong odor from the yeast, but the material inside is harmless and can be hosed down with plain water. Panel, Jackson and Delta traps can be picked up and placed back into the tree by the homeowner or resident, although if you do so, please be sure to handle the trap carefully. Panel traps are very sticky, and the cotton wick inside the Jackson and Delta traps has a trace amount of a pesticide used to kill the fly, so please don’t touch them without gloves. You may also contact us and we will immediately make arrangements to rehang the trap.

14. Aren’t insects an important part of nature?

Yes, they are! However, non-native insects have no natural predators here to keep a population in control. By controlling exotic pests, we are protecting agriculture, gardens, and our environment.

15. What can I do to help the pest detection trapping program?

You can help by:

1. Welcoming the detection traps featured on this page.

2. Report any unusual or targeted insects or plant conditions. You can report this to our department, the University of California Master Gardeners of Contra Costa, or the California Department of Food and Agriculture Pest Hotline at 1-800-491-1899.

3. Follow any quarantine restrictions that apply to your property.

4. When returning to California from an out-of-state trip, do not bring back prohibited fruits, vegetables, and other plants with you.

5. Discourage your family and friends outside of California from sending backyard produce or plants in the mail. If you do want to send these things, contact our office so we can help you to determine if you can do it safely. Visit the California Department of Agriculture’s information on bringing plants and animals into California and guide for bringing fruit and vegetables into California (PDF) to find out what is prohibited.