Trees above the pond ten years ago.
Trees above the pond in the fall of 2020.
Emerald Ash Borer October is my favorite time of year because nature will give us a great show of dazzling colors. The leaves turn into deep red, golden yellow and brown, and everything is almost breathtaking. This year our reds are more deep than I remember and the yellows almost sparkle. But there is trouble in paradise. There is a catastrophe unfolding; the Emerald Ash Borer (EAB), has done an efficient job of robbing us of so many ash trees! You will see them still standing with no leaves amongst the other trees in full cover.
We had our woods logged six years ago and the logger took all the marketable ash trees that were 16 inches in diameter at chest height and were still healthy. He explained to us that in five or six years they would be infected and the wood would be worthless. He was spot on it appears. Today 90% of our ashes are dead or declining quickly.
We had our woods logged six years ago and the logger took all the marketable ash trees that were 16 inches in diameter at chest height and were still healthy. He explained to us that in five or six years they would be infected and the wood would be worthless. He was spot on it appears. Today 90% of our ashes are dead or declining quickly.
Even our few 120+ year old trees that survived their changing surroundings, are in decline. They grew up next to the open fields the original settlers cleared, and they sprouted and avoided being grazed away by livestock.. They then competed with other trees, as those fields were abandoned and left to nature, transitioning to sapling crowded thickets that competed with them for light and nutrients, and they survived against browsing deer. Finally, they were robust woodland sentinels, with multiple tiers of branches, spreading more offspring around them.
Sadly today, even these survivors are showing stress as well, and may be the last to fall. The loggers that came behind them were not interested in them because- as they had grown up, next to, or in an open field, their branches were many and spread in all directions to catch the light. Their branches, knots and flaws were scattered randomly through the trunk, which gave them absolution from the loggers axe. Only straight grained trees from crowded middle/older growth woods are desirable.
So what about our trees now? You do not see it from the outside; usually they just break and fall. We went through such an “event” last week. We had a little wind and suddenly the power went out. One of the ashes fell on the electricity line. It took the provider almost ten hours to repair it.
So what about our trees now? You do not see it from the outside; usually they just break and fall. We went through such an “event” last week. We had a little wind and suddenly the power went out. One of the ashes fell on the electricity line. It took the provider almost ten hours to repair it.
Holes from a hunting woodpecker If you have ashes on your property, look for signs of infection. Look at the bark from a few meters (yards) away. Mature ash bark is a mottled light gray to black. If you can see small beige spots from that distance, take a closer look. If those spots are actually from the bark being chipped out, exposing the inner wood. Then it may be a sign that the woodpeckers are chasing the emerald ash borer under the bark already, and you may have to take action. Another sign would be seen on the outermost branches. If the leaves on the furthest extremities of the crown appear significantly smaller than the leaves closer to the main trunk, then this may be a sign of distress, as the tree is struggling to pump up enough water to support them. Once in the tree, the borer disrupts the flow of water and nutrients up and down the whole tree. Now, in the Fall- at this time of year, if your ashes are shedding their leaves much earlier than the other trees, it is also a bad sign.
If you have a valued ash tree on your property that you really want to save, you can have it treated chemically by an arborist, but it will be a yearly treatment for the rest of its life. I recently visited Midland Michigan, and they were aggressively treating their trees, as decades ago they planted their ashes as a large part of their arboreal urban/suburban landscapes. Today they are majestic, tall shade trees and the community has decided it is worth the expense and effort to save them.
What can we do to stop losing all of our valuable ashes? Unfortunately probably nothing ultimately. We don’t have any clever chemical or mechanical means. Using biological weapons- like introducing a lethal fungus or natural predator for this invasive species into the mix, is fraught with unexpected consequences. And although this is always a consideration, we are not likely to do this.
In the eastern U.S. we have gone through many blights. In the early 1900's the chestnut blight killed all of them and changed the forest forever. Our old barn, which was built in the1850’s out of old growth chestnut, is still going strong. After the chestnut blight, the elms were killed by an exotic bark beetle. Then we lost almost all our beeches, which after 30 years are coming back now. And now the Emerald Ash Borer (EAB), an Asian insect, which was first discovered twenty years ago in Detroit, Michigan. It is assumed that it was hidden in wooden crates or packing material from China. It is the most destructive insect ever to invade the U.S. So far it has killed millions of ash trees and was found first in 18 states, along with Ontario and Quebec, and then in all the eastern United States. I still remember when I first saw the purple EAB trap in our County, trying to confirm that it had arrived. Somehow I cannot help thinking of Covid19 now!
In the eastern U.S. we have gone through many blights. In the early 1900's the chestnut blight killed all of them and changed the forest forever. Our old barn, which was built in the1850’s out of old growth chestnut, is still going strong. After the chestnut blight, the elms were killed by an exotic bark beetle. Then we lost almost all our beeches, which after 30 years are coming back now. And now the Emerald Ash Borer (EAB), an Asian insect, which was first discovered twenty years ago in Detroit, Michigan. It is assumed that it was hidden in wooden crates or packing material from China. It is the most destructive insect ever to invade the U.S. So far it has killed millions of ash trees and was found first in 18 states, along with Ontario and Quebec, and then in all the eastern United States. I still remember when I first saw the purple EAB trap in our County, trying to confirm that it had arrived. Somehow I cannot help thinking of Covid19 now!
The EAB is very good at finding ash trees that are stressed or injured, noticeably with purple and green leaves. First they nibble along leaves and then they lay eggs, pushing them into bark indentations. The larvae hatch in mid-summer and chew through the outer bark to reach the inner layer (phloem). The tree needs it to transport carbohydrates from the tree crown to the roots. The larva keeps making tunnels and forms a ring around the inner trunk (out of your sight), thus girdling the tree and stopping water transportation from the roots to the top of the tree. If it has hundreds or thousands of larvae, the tree gets strangled and it starves.
Scientists have found that most EAB stay within about a half a mile from where they first were spotted. A few of the females however are able to fly three miles and find new ash trees.
Scientists have found that most EAB stay within about a half a mile from where they first were spotted. A few of the females however are able to fly three miles and find new ash trees.
Unfortunately, we have helped the EAB to move further. Infested ash trees have been sold by nurseries or sold as firewood. Although an infested ash tree trunk will not be infected again, any larvae under the bark will go through the regular life circle and emerge as adults. So just because your wood is cut and down, doesn't mean that EAB won't escape into the local environment! In NYS, it is illegal to transport firewood more than 50 miles from its source, without a certification that it has been kiln heated to at least 160 degrees Fahrenheit for 75 minutes.
In China the EAB is only a secondary pest, attacking only dying ash trees. Because it is an indigenous species there, it has natural controls. We don't have that, and trying to import those natural controls could be even more dangerous. The ash trees in North America have no- or only few, defenses to resist this pest.
In China the EAB is only a secondary pest, attacking only dying ash trees. Because it is an indigenous species there, it has natural controls. We don't have that, and trying to import those natural controls could be even more dangerous. The ash trees in North America have no- or only few, defenses to resist this pest.
The economic impact of the loss of ash trees is enormous. I have read that eight billion ash trees were lost in the last decade which are valued at $280 billion. And it will get more expensive when all the dead ash trees have to be removed before or after they fall down. This will lead to more power outages and insurance claims as time and storms claim them.
There is much hope that a native tiny wasp might come to the rescue. It has not been studied enough, but it seems to have become more common where ashes are dying, teasing the hope that the wasp's numbers are increasing because they are preying on EAB? . If this native predatory wasp is expanding in response to the explosion of EAB, that would be possibly great news. Perhaps nature will save us with a home grown predator. Unfortunately, this is all 'blue sky' wondering. We don't have a solution right now. Considering all the other invasive species stories in this country resulting from global trade, the prospects are grim.
Scientists have tried insecticides and tree girdling or “SLAM” (Slow Ash Mortality), before the larvae can go to work. Scientists hope to slow the death of all ash trees, but it is a struggle.
It seems likely that we have to kiss millions of ash trees goodbye, before we find a solution. We sincerely hope not!!
There is much hope that a native tiny wasp might come to the rescue. It has not been studied enough, but it seems to have become more common where ashes are dying, teasing the hope that the wasp's numbers are increasing because they are preying on EAB? . If this native predatory wasp is expanding in response to the explosion of EAB, that would be possibly great news. Perhaps nature will save us with a home grown predator. Unfortunately, this is all 'blue sky' wondering. We don't have a solution right now. Considering all the other invasive species stories in this country resulting from global trade, the prospects are grim.
Scientists have tried insecticides and tree girdling or “SLAM” (Slow Ash Mortality), before the larvae can go to work. Scientists hope to slow the death of all ash trees, but it is a struggle.
It seems likely that we have to kiss millions of ash trees goodbye, before we find a solution. We sincerely hope not!!
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