Media Questions and Answers

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1. Why is WSDA so concerned about keeping permanent populations of gypsy moths out of Washington?

2. Which 19 states have permanent populations of gypsy moth?

3. How extensive is the damage in the 19 states with permanent populations?

4. How much does WSDA spend a year on gypsy moth control?

5. Exactly how does the gypsy moth damage the environment?

6. Exactly how does the gypsy moth damage the economy?

7. How many gypsy moth eradication treatments have been conducted in Washington?

8. How many treatments have been successful?

9. How does WSDA define a successful treatment?

10. Why is the gypsy moth so much more destructive than other pests?

11. What is WSDA’s legal authority to conduct summer trapping and spring eradication programs?

12. Isn’t it a conflict of interest for WSDA to both propose an eradication treatment and then decide whether or not to approve it?

13. Who has the final say whether a gypsy moth eradication treatment is conducted?

14. What determines the size of a gypsy moth eradication zone?

15. What determines whether an eradication treatment is conducted with ground equipment or aircraft?

16. WSDA talks often about "pest insects". How do you define a pest insect?

17. How does WSDA distinguish between a gypsy moth "introduction" and "infestation"?

18. What trees commonly found in Washington would be particularly impacted if the gypsy moth were permanently established here?

19. What kind of eradication treatments have been conducted in Washington state?

20. Which of the six treatments has WSDA used the most?

21. Does Btk have any disadvantages?

22. I have read several accounts on the Internet of people suffering adverse health effects after Btk treatments. Just how safe is the insecticide?

23. So Btk is not safe in every instance?

24. What common sense precautions do public health officials recommend people take after Btk treatments?

25. Why won’t WSDA release the inert ingredients of Btk?

26. What are the advantages and disadvantages of the other five eradication methods?

27. Why are so many people in general opposed to Btk?

28. Why were so many Seattle residents opposed to Btk treatments in Ballard/Magnolia in 2000 and Crown Hill neighborhood in 2002?

29. What does WSDA say to a citizen who calls and asks how they can stop a Btk treatment?

ANSWERS

Question 1: Why is WSDA so concerned about keeping permanent populations of gypsy moths out of Washington?

Answer: WSDA doesn’t want the worst forest pest insect ever to enter the U.S. to become permanently established in the state. We have seen the damage done to the environment and economy in the 19 states in the East and Midwest where permanent populations exist. We don’t want that to occur in Washington. It would have a catastrophic impact on our environment and economy.

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Question 2: Which 19 states have permanent populations of gypsy moth?

Answer: Connecticut, Delaware, Illinois, Indiana, Maine, Massachusetts, Maryland, Michigan, New Hampshire, New Jersey, New York, North Carolina, Ohio, Pennsylvania, Rhode Island, Vermont, Virginia, West Virginia, and Wisconsin.

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Question 3: How extensive is the damage in the 19 states with permanent populations?

Answer: Very extensive. Hundreds of thousands of acres in the 19 states annually are defoliated, quarantined, and sprayed. Two examples illustrate the amount of damage that occurs: In 2008 in New Jersey 30,900 acres of trees died in the state as a result of repeated gypsy moth defoliation. In 2009 in Maryland 37,000 acres of vegetation were aerially sprayed to suppress existing infestations. By way of comparison the largest eradication treatment in Washington in the last 10 years has been over one square mile or 725 acres.

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Question 4: How much does WSDA spend a year on gypsy moth control?

Answer: About $1 million, of which about half is provided by the federal government. Approximately 75 percent of gypsy moth control money is spent on summer trapping, and 25 percent on eradication.

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Question 5: Exactly how does the gypsy moth damage the environment?

Answer: By weakening and killing trees and plants, destroying wildlife habitat, degrading water quality of creeks and streams, and reducing the use and aesthetic value of recreation areas.

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Question 6: Exactly how does the gypsy moth damage the economy?

Answer: By destroying or damaging plants, trees, and shrubs; by triggering costly quarantines of agriculture, nursery, and timber products; and by reducing tourism. Visitors don’t visit locations infested with caterpillars.

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Question 7: How many gypsy moth eradication treatments have been conducted in Washington?

Answer: Eighty six. The first treatment was conducted in 1979, the most recent one in 2007. Sixty-five treatments have been ground treatments, 16 have been aerial treatments, and five have been joint air-ground treatments.

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Question 8: How many treatments have been successful?

Answer: All of them. Washington has never had a permanent population of gypsy moth.

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Question 9: How does WSDA define a successful treatment?

Answer: Two consecutive summers of negative trapping following an eradication treatment. Eradication treatments occur in late spring. Summer trapping occurs from July-September. If no moths are caught for two consecutive summers, the treatment is declared a success.

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Question 10: Why is the gypsy moth so much more destructive than other pests?

Answer: Because it feeds on more than 500 species of trees and plants, and reproduces very rapidly. A single female moth can produce up to 500 females the following spring.

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Question 11: What is WSDA’s legal authority to conduct summer trapping and spring eradication programs?

Answer: Revised Code of Washington (RCW) 17.24.101 (Statewide survey and control activity) and RCW 17.24.021.

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Question 12: Isn’t it a conflict of interest for WSDA to both propose an eradication treatment and then decide whether or not to approve it?

Answer: No. State law directs WSDA to survey for the presence of destructive pests; propose eradication treatments when infestations are located; prepare assessments of the impact of the eradication proposals on the environment; make the assessments available for public review and comment; and then approve or disapprove the proposals based on all evidence presented.

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Question 13: Who has the final say whether a gypsy moth eradication treatment is conducted?

Answer: The people of the state of Washington. They exercise this authority through public officials they elect to office, the state’s judicial system, or in some cases directly.

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Question 14: What determines the size of a gypsy moth eradication zone?

Answer: Where gypsy moths were caught, where other evidence of gypsy moth activity in the area was detected, and host vegetation in the area.

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Question 15: What determines whether an eradication treatment is conducted with ground equipment or aircraft?

Answer: WSDA prefers to conduct treatments with ground treatments. However, WSDA will use aircraft when the size or typography of a proposed treatment zone make it prohibitively expensive to administer the treatment with ground equipment.

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Question 16: WSDA talks often about "pest insects". How do you define a pest insect?

Answer: An insect that infects people or domesticated animals with diseases, or competes with people for food, fiber, or living space.

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Question 17: How does WSDA distinguish between a gypsy moth "introduction" and "infestation"?

Answer: An introduction is a first-time detection. An infestation is a conclusion, made by state entomologists, that a reproducing population of gypsy moth is present. Most introductions die out on their own. Conclusions that reproducing populations are present are based on multiple catches in close proximity to each other over multiple years, or evidence of other gypsy moth activity detected in an area (e.g., egg masses, pupal cases, cast skins, of dead moths found on the ground).

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Question 18: What trees commonly found in Washington would be particularly impacted if the gypsy moth were permanently established here?

Answer: Oak, apple, hawthorne, poplar, willow, and maple.

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Question 19: What kind of eradication treatments have been conducted in Washington state?

Answer: At various times in the past WSDA has conducted the following six eradication treatments:

1. Mass trapping, the use of small cardboard traps containing pheromones to attract male moths.
2. Mating disruptions, aerial applications of tiny plastic containers containing pheromones that attract male moths.
3. Sterile insect technique, the release of sterile male moths to confuse male moths.
4. Gypchek, a microbial insecticide.
5. Dimlin, a chemical insecticide.
6. Bacillus thuringiensis var. kurstaki (Btk), a biological insecticide found naturally in soil.

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Question 20: Which of the six treatments has WSDA used the most?

Answer: Btk. The biological insecticide is a very effective eradicant. It has been used successfully on gypsy moth infestations in Washington and other states since the 1980s; has a proven safety record with people, pets, birds, fish, livestock, and other insects such as bees; has been registered and re-registered many times by the Environmental Protection Agency (EPA) for use in the U.S., to use on more than 200 food and fiber crops.

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Question 21: Does Btk have any disadvantages?

Answer: Yes. The insecticide must be ingested by the gypsy moth caterpillar to be effective. Also the pesticide breaks down quickly and therefore requires three to five treatments each year to be effective, and is very sensitive to weather. Scheduled treatments are often postponed.

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Question 22: I have read several accounts on the Internet of people suffering adverse health effects after Btk treatments. Just how safe is the insecticide?

Answer: Some people have reported mild skin reactions or mild eye, ear, and nose irritations after Btk treatments. Others have reported mild hay fever reactions. Health officials have studied these reports extensively and have not been able to determine if the reactions were caused by Btk or by pollens, molds, or dust generated during the treatments, or were unrelated to Btk treatments. Public health officials state Btk is not a public health risk.

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Question 23: So Btk is not safe in every instance?

Answer: Nothing in science is safe in every instance. The back of our hands contain caner-producing agents in very, very low numbers. Health officials state the risk to human health from Btk is very, very low.

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Question 24: What common sense precautions do public health officials recommend people take after Btk treatments?

Answer: Remain indoors for at least 30 minutes after a spray application, particularly those with leukemia, HIV, respiratory disorders, other immune deficiencies, those receiving radiation or chemotherapy, those with allergies, and those prone to respiratory irritation. Children should wait until moisture from the spray and dew has dried on grass and shrubs before playing outside. If you come in contact with the wet spray, wash the affected skin with soap and water.

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Question 25: Why won’t WSDA release the inert ingredients of Btk?

Answer: State and federal law prohibits the release of the information without the manufacturer’s release. The rationale for this law is that other manufacturers could then replicate the product. However, the law allows for public health officials -- after signing a non-disclosure agreement -- to review all ingredients of Btk and then comment in general terms about the safety of the insecticide. This has been done repeatedly in the past in Washington before Btk treatments. Local public health officials have always reported Btk doesn’t represent a serious public health risk.

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Question 26: What are the advantages and disadvantages of the other five eradication methods?

Answer:

1. Mass trapping. Advantage: Target specific, and pinpoints center of population. Disadvantage: Not a proven eradication method.
2. Mating disruption. Advantage: Target specific. Disadvantages: a. Not a proven eradication method; blinds summer trapping program in treatment areas; and effective adjuvant for mating disruption not registered in Washington state.
3. Sterile insect release. Advantage: Target specific; minimal impact on environment. Disadvantage: Very expensive because it involves large rearing operation.
4. Gypchek. Advantage: Target specific. Disadvantage: Not a proven eradication method; most effective with high populations, not low populations.
5. Dimlin. Advantage: Proven eradication method. Disadvantages: a. Very persistent; remains in environment for long period; and toxic to many non-target insects.

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Question 27: Why are so many people in general opposed to Btk?

Answer: People opposed to Btk are small in number. A handful of activists are opposed to Btk, usually because they are misinformed about the damage and biology of the gypsy moth, the effects of Btk, or have chosen to ignore the information.

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Question 28: Why were so many Seattle residents opposed to Btk treatments in Ballard/Magnolia in 2000 and Crown Hill neighborhood in 2002?

Answer: The vast majority of Seattle residents were very supportive of the treatments. A handful of activists were opposed, not the residents.

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Question 29: What does WSDA say to a citizen who calls and asks how they can stop a Btk treatment?

Answer: We first listen to their concerns and try to answer their questions. Then we try to inform them about the damage and biology of the gypsy moth, the effectiveness and proven safety record of Btk, and ask them to support – not oppose -- the treatment.

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