by Chloe Kiparsky
The view from almost anywhere in the city of Ouray is of trees, a lot of trees, and an alarming number of them dead or dying. If we zoom in very close to one of these dying trees, more often than not we will see colonies of small bugs infesting their bark. These are bark beetles, the nearly invisible destruction of our forests.
County Commissioner Ben Tisdel has been working on the problem of bark beetles for the last four years. “They burrow under the bark of the tree,” he said, “and then kind of make a ring around the tree between the wood and bark - it's called the cambium layer - and that ring basically prevents the tree from sending moisture up and down through its trunk. That’s what kills the tree.”
Each tree species has its own beetle that infests it, and a strong forest is made up of more than one tree species. “One of our saving graces is that we don't have a monoculture of trees in our forests,” said fourth-grade teacher Jenny Hart, “here we have a really good diversity of trees so while we have many trees that are brown and dead, so many of our trees are not affected; they're still beautiful and healthy.” She reflected on her travels in the state. “There are places in Colorado that have been hit by beetles and all of the trees died. That's just awful”
The bark beetle epidemic in Ouray peaked in 2018, and it seems to be getting a little better now. One thing that very much affects the number of bark beetles is water levels. When the tree has enough water, it can “produce enough sap to encapsulate and kill the beetle that's invading it,” said Tisdel, but that’s not always the case. “In a drought year the trees don't have enough water to do that,” he explained.
There was severe shock among the human population of Ouray when the beetles were at their height. “In six months we watched the forests die,” remarked Ms. Jenny. “It was alarming, it was jaw-dropping and it was scary to watch it.”
Common as this sentiment was three years ago, the fear seems to have faded. Now, she lamented, “I feel like people have grown used to it. It’s become normal to people who live here and they have become habituated to it and aren't really paying attention to it anymore.”
Todd Cline, who has lived in Ouray for 52 years, has watched the transformation of our forest. He said that, before the beetle epidemic, a common thing heard in his family was “Gosh, where are we gonna find dead trees to cut this year for firewood?”
Bark beetles are not just dangerous to our forests, they are dangerous to us. “I'm really concerned that we have all this dead wood lying on the ground very close to town,” said Ms. Jenny, “I have a really hard time even getting people to want to talk about that, and if we don't get serious about this as a community we're going to be sorry.”
Mr. Cline, knowledgeable about wood due to his many years of chopping his own firewood, concurs with Ms. Jenny. The beetles “significantly add to fire danger,” he said. “In 1980 you looked up and there were hardly any dead trees. Now it's a forest of dead trees.” At this, he looked out the window to all the brown trees framing the Amphitheater.
A method that has been successfully used in the past to fight the beetles in Ouray is putting pheromone packets on the trees. Tisdel explained that when the beetles infest a tree they send out a pheromone, a chemical message, telling other beetles to not lay eggs in that tree because beetles are already using it. He went on to say that it is called “an anti-aggregate pheromone” and that scientists have been able to “synthetically produce that pheromone for one tree species” so far.
“We've done a program during the right time of year - generally during early spring - where we sent people out to staple these little packets of anti aggregate pheromones on these trees. If you do that in a certain way it can save that particular tree species,” he said.
Thinning the forests is another method Tisdel mentioned: “It does help to thin forests out so trees don't compete against each other for limited water resources in drought years,” commented Tisdel. The costs and logistics of this method, however, in our remote and rugged woods, makes it challenging in practice.
County Commissioner Ben Tisdel has been working on the problem of bark beetles for the last four years. “They burrow under the bark of the tree,” he said, “and then kind of make a ring around the tree between the wood and bark - it's called the cambium layer - and that ring basically prevents the tree from sending moisture up and down through its trunk. That’s what kills the tree.”
Each tree species has its own beetle that infests it, and a strong forest is made up of more than one tree species. “One of our saving graces is that we don't have a monoculture of trees in our forests,” said fourth-grade teacher Jenny Hart, “here we have a really good diversity of trees so while we have many trees that are brown and dead, so many of our trees are not affected; they're still beautiful and healthy.” She reflected on her travels in the state. “There are places in Colorado that have been hit by beetles and all of the trees died. That's just awful”
The bark beetle epidemic in Ouray peaked in 2018, and it seems to be getting a little better now. One thing that very much affects the number of bark beetles is water levels. When the tree has enough water, it can “produce enough sap to encapsulate and kill the beetle that's invading it,” said Tisdel, but that’s not always the case. “In a drought year the trees don't have enough water to do that,” he explained.
There was severe shock among the human population of Ouray when the beetles were at their height. “In six months we watched the forests die,” remarked Ms. Jenny. “It was alarming, it was jaw-dropping and it was scary to watch it.”
Common as this sentiment was three years ago, the fear seems to have faded. Now, she lamented, “I feel like people have grown used to it. It’s become normal to people who live here and they have become habituated to it and aren't really paying attention to it anymore.”
Todd Cline, who has lived in Ouray for 52 years, has watched the transformation of our forest. He said that, before the beetle epidemic, a common thing heard in his family was “Gosh, where are we gonna find dead trees to cut this year for firewood?”
Bark beetles are not just dangerous to our forests, they are dangerous to us. “I'm really concerned that we have all this dead wood lying on the ground very close to town,” said Ms. Jenny, “I have a really hard time even getting people to want to talk about that, and if we don't get serious about this as a community we're going to be sorry.”
Mr. Cline, knowledgeable about wood due to his many years of chopping his own firewood, concurs with Ms. Jenny. The beetles “significantly add to fire danger,” he said. “In 1980 you looked up and there were hardly any dead trees. Now it's a forest of dead trees.” At this, he looked out the window to all the brown trees framing the Amphitheater.
A method that has been successfully used in the past to fight the beetles in Ouray is putting pheromone packets on the trees. Tisdel explained that when the beetles infest a tree they send out a pheromone, a chemical message, telling other beetles to not lay eggs in that tree because beetles are already using it. He went on to say that it is called “an anti-aggregate pheromone” and that scientists have been able to “synthetically produce that pheromone for one tree species” so far.
“We've done a program during the right time of year - generally during early spring - where we sent people out to staple these little packets of anti aggregate pheromones on these trees. If you do that in a certain way it can save that particular tree species,” he said.
Thinning the forests is another method Tisdel mentioned: “It does help to thin forests out so trees don't compete against each other for limited water resources in drought years,” commented Tisdel. The costs and logistics of this method, however, in our remote and rugged woods, makes it challenging in practice.