SPEAKOUT: Synthetic pheromone packets a safer way to fight mountain pine beetle infestations

By Christine Weeber

Published July 6, 2008 at 12:05 a.m.

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Pesticides often have larger effects than we intend. Some of those used in responding to the mountain pine beetle infestation are no different. Carbaryl, the active ingredient in the most common sprays used to protect trees against beetles, is one of these. It is a neurotoxin that is dangerous to humans and pets through skin contact, inhalation and ingestion through food or water. And it is highly toxic to bees, stoneflies and some fish.

In 2005, 12 groups representing farmworkers, beekeepers and environmentalists called on the Environmental Protection Agency to cancel carbaryl due to the unreasonable risks associated with it. In 2007, the EPA restricted many pet and home uses of it.

Though carbaryl (trade names: Sevin, Tercyl, Adios, Carbamec) has been found in water supplies, both the U.S. Forest Service and Rocky Mountain National Park are spraying thousands of trees with it here in Colorado.

What risk does this pose to downstream water users? Forty percent of Boulder's water is from Barker Reservoir, so it is of great concern that the Silverthorne/Dillon Joint Sewer Authority declared they found carbaryl in the Silverthorne plant effluent (i.e., treated water) in 2007.

But there is an alternative. Pheromone packets, called Beetle Block, are a recently approved eco-friendly option. These contain Verbenone, a synthetic pheromone, and are hung on trees to repel beetles by sending a message that a tree has reached maximum beetle saturation. The EPA says there is no risk expected to humans or the environment from Verbenone.

The packets need to be placed on trees before the beetles fly in early summer. Beetle Block has been most successful when used as part of an overall plan to thin forests and remove infested trees, and when used in forests that are less than 20 percent infested. Though relatively less successful than carbaryl, Beetle Block is not toxic.

In three-year tests in Montana, the packets successfully protected trees from beetles. In another study, mass attack was reduced to an average of 3.6 percent; in untreated areas, 48.3 percent of trees were mass attacked. In 2005, the Bark Beetle Technical Working Group stated that Verbenone was effective in protecting trees in many instances from beetles.

Some homeowners have also placed mulch around the base of trees and used drip irrigation systems to water three to four times a month during warmer months.

If landowners do decide to spray, they should alert neighbors so they can close their windows and keep their children and pets inside. Please also post a sign so people know what trees have been sprayed. Rocky Mountain National Park posts signs for 60 days after spraying trees in the park (and people are kept 200 feet away from sprayed trees for at least 12 hours).

Christine Weeber is a resident of rural Golden.

• July 6, 2008

  1:03 a.m.

  Suggest removal

  Patron_Drinker writes:

  I'd like to know what "relatively less successful" means in this case. Polio was "relatively less successful" against FDR than most of its victims. John Hinckley was "relatively less successful" than Lee Harvey Oswald.

  Also the line about mulch and watering doesn't make sense with the rest of the piece

• July 6, 2008

  9:48 a.m.

  Suggest removal

  Dhakala writes:

  This pheromone "repel(s) beetles by sending a message that a tree has reached maximum beetle saturation." So where do the homeless beetles go? I would guess they fly farther to untreated trees in someone else's forest, unless they just drop dead on the way. Very large areas would have to be hung with packets, one tree at a time, in order to ensure the latter outcome. It seems impractical.

• July 6, 2008

  10:57 a.m.

  Suggest removal

  HolierThanThou writes:

  Beetles start by emitting an attractive pheromone so they can overwhelm the tree's defenses. When the tree is full of beetles, they emit a "no vacancy" pheromone, which is what verbenone is.

  The pheromone packets are effective when combined with harvesting of infested red trees before the next generation of beetles flies. After cutting the infested wood, it needs to either be baked or covered with black plastic that is tightly sealed so that the beetles cannot escape. Usually a mound of dirt and rocks around the edges will suffice if the mound is heavy enough to prevent wind from blowing the plastic away. You may also stake and tie the cover down.

  I've tried carbaryl. It's poisonous to more than just pine beetles. Rain washes it off the trees leaving them unprotected, so some of them get infested anyway. I can hang the pheromone packets so they stay put.

  The pheromone tricks the beetles into leaving valuable trees alone. But if you or your neighbors refuse to cut and stow infested trees then they'll be waiting just outside your defended zone to jump back in. The same problem exists even if you apply pesticide because it doesn't make much of a dent in the local beetle population. If the advance beetles die when they hit the tree, the other beetles don't smell success and move on to another.

  Beetle Block is only going to be effective for treating valuable old trees on private property or in small parks. Public lands are a lost cause. Chalk one up for global warming and milder winters. The good news is that pine beetles don't infest young trees. As the old stands are killed off, the beetles make themselves homeless and they, too, die off. Then the trees grow and the cycle begins again.

• July 6, 2008

  3:04 p.m.

  Suggest removal

  ezekiel777 writes:

  having sucessfully fought the pine beetle in ponderosa pine forestland for over 20 years, Sevin proved remarkably effective at stopping the infestation. 30 plus local landowners teamed together each year to spray their acreges. a few declined to partake and those who failed to spray lost ALL their trees within a year.

  the plan included thinning trees and removing infected and/or dead trees... combined with the preventative annual spraying. it worked.

  the untreated national forest land was devastated by the pine beetles which later contributed to the largest forest fire experienced by the region in recorded history. (15K acres of an 50 sq. mile area.)

  during our spraying campaign period there were no ill effects experienced by anyone, at any time...period. it simply didn't happen.

  i'd use sevin again without question.

• July 6, 2008

  5:44 p.m.

  Suggest removal

  evergreenres writes:

  OK, this sounds great. Where can we get it? What does it cost? Where do we learn more?

• July 7, 2008

  1:16 p.m.

  Suggest removal

  Menno writes:

  This article is unfortunately the perfect example of the harm stereo typing does, and the importance of doing your homework before you report on something.

  My company www.techmist.com treats many tens of thousands of trees here in British Columbia and Alberta ( Canada ).

  We loose less than half of 1% of all sprayed trees.

  We use pheromones combined with spray to achieve these results. The pheromones are referred to as the ‘floating defense’ as the ‘odor’ is carried by the wind, and we have good results with that under light to medium beetle pressure. The Spray is referred to as the ‘fixed’ defense and has incredible results if sprayed 60 to 80 ft high and the proper 3 stage treatment is observed for the chemical to make it last on the trees. ( if these are not followed the Sevin will last for less than a month and the tree is then unprotected. )

  We have studied Carbaryl for years and seen and learned from direct contact with myself and our sprayers and non target pests it hits, what happens to them.

  Sevin Facts

  -Sevin does not translocate through soil so there is minimal danger to groundwater pollution
  -Sevin breaks down rapidly depending on what it is applied to.
  -Concrete Half-life is 15 minutes
  -mammals neutralize it within minutes and then remove it from body completely within 24 hours
  -It is almost impossible to have your self tested for Carbaryl poisoning if small quantities are absorbed due to the rapid breakdown in our systems.
  -Birds are 4 times more resistant than mammals
  -Sevin is applied in spray form directly to Poultry, Cattle and horses as well as pets to control Mites and tics
  -After World War 2 Churchill had all citizens of London ‘powder Coated’ with the ‘white miracle powder’ to eliminate disease carrying fleas.

  An average human would need to consume ( and keep in their gut for 4 hours ) 8-10 square yards of Bark treated with our Sevin mix to reach a lethal oral dose.

  An average human would need to bathe in 32 liters of our Sevin mixed as is in our tanks for 4 hours to gain a lethal dermal dose.

  Continued in next posting

  Menno Koehoorn
  www.pine-bug.com

• July 7, 2008

  1:18 p.m.

  Suggest removal

  Menno writes:

  Regarding the killing of beneficial pests. The trees are not sprayed to the top so there would be a nursery culture that would quickly take over the tree after Sevin spraying has stopped. Don’t forget that millions of acres of land are treated with Sevin for Grasshoppers and Aphids year in, year out, by farmers and the pests always find ways to come back in droves to destroy crops.

  Regarding Bees, I have talked to Apiarists extensively and you will not wipe out a hive by contacting one bee with the product. On the contrary, a customer just last week had to get rid of a rogue hive and sprayed it down three times directly to wipe them out, as they definitely did not ‘drop like flies’ ( he tried to get the hive removed several times and no one would move them for him as they were concerned about disease. )
  
  Regarding finding carbaryl in water systems, it so rapidly breaks in microbial rich water, especially where the PH is above 7 that the concern for safety is extremely low.

  Sevin is NOT a carcinogen ( does not cause cancer )
  Sevin is NOT a mutagen ( does not cause mutations in the genetic code )

  For more info we have charts in our website that show the comparisons between Carbaryl and other products we use daily, including Caffeine. ( eg. it takes 52 cups of coffee in one day to kill a human ) Paste this link in your address bar...

  http://www.techmist.com/products_we_o...

  You CAN save your trees. It is successful. You can treat your trees for more than 10 years with Sevin till you break even with the cost of removing your tree and you end up with live, beautiful trees. Generally the epidemic moves through quickly ( slower at higher elevations) and should be 3-7 years of treatment required.

  I hope this helps you, and if you have questions feel free to call or email us.

  Thanks for your time and interest and we encourage you to save your trees.

  IT WORKS!

  Menno Koehoorn
  www.pine-bug.com
  Tech Mist Spray Solutions Inc.

• July 7, 2008

  1:45 p.m.

  Suggest removal

  MAC1975 writes:

  Verbenone is not without risks. According to the company’s fact sheet, it is an irritant eyes and skin and to the lungs, if inhaled. If you have curious kids running around on your property, who may open one of the packets, this may not be for you.

  Keep in mind that Verbenone does not work when the beetle reaches high concentration levels like they are in may places in Colorado. Chris even says that it only works when the beetle is at 20%. The current epidemic levels are certainly higher than that in many places in Colorado.

  Thinning may not be the answer.
  Densely populated lodgepole pine stands contain shallow rooted trees that are very susceptible to blow down once thinned. Thinning in lodgepole has not offered the protection it has in past epidemics.

  Broad-brush advice is not environmentally sound to anyone.
  The best advice to an individual landowner is to start with your land and look at it closely with a professional. What you do should be decided by the conditions of your individual property and what your objectives for that land are in the future. It is always a good idea to get the opinion of a forester when dealing with large acreages or an arborist if dealing with one or two trees in your yard. Contact the local county extension agent, the Colorado State Forest Service or the Society of American Foresters for a referral for someone who has the right credentials for the job! If you live on the Front Range, visit www.frontrangebeetle.org or for other areas visit www.fs.fed.us/r2/bark-beetle Both these sites contain lots of links and information about the beetle and what the USFS and local governments are doing.

• July 7, 2008

  7:45 p.m.

  Suggest removal

  Menno writes:

  For treatment in Colorado contact Timberline spraying at toll free number - (866) 687-6811.
  Don Doti has amazing results and treats over 100,000 trees anually!

• July 8, 2008

  6:16 p.m.

  Suggest removal

  BobBronson3 writes:

  Thanx for the article, Christine Weeber, but you didn't say where Beetle Block can be purchased and its cost.

  Than in advance for your response.

  Sincerely,

  Bob Bronson

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