The Heartbeat of Trees by Peter Wohlleben;

Author:Peter Wohlleben;
Language: eng
Format: epub
Publisher: Lightning Source Inc. (Tier 2)
Published: 2021-06-15T00:00:00+00:00

19 When a Tree Needs a Doctor

OUR LOVE OF nature often means we want to get involved and help when one of our fellow creatures falls ill. We especially like looking after species that are closely related to us (mammals) or life-forms that are particularly impressive, like trees. And because there are lots of trees around the places where we live, we single them out for our care and attention.

When old trees in the city begin to rot, we usually go on high alert. What is at stake here is not only the survival of a large plant but, more importantly, the safety of residents. A falling tree weighing hundreds of tons can do a massive amount of damage. Arborists arrive to assess whether the giant can be saved or whether it needs to be removed. In years past, arborists obviously spent too much time watching dentists: rotting trees were treated like rotting teeth. The rot was scraped out, and then the area was drilled and, finally, filled—not with a metal amalgam but with concrete. That sounds fine, doesn’t it? After all, a concrete filling should provide a tree with the stability it needs. But a tree trunk is not a rigid structure. Wood is a combination of fibers and glue, and it flexes like fiberglass. A concrete core makes it impossible for a trunk to flex. It would be like inserting a steel rod in a human spine—you’d no longer be able to move around freely.

For the tree, restricted movement means the topmost branches are more likely to break off in a storm. Also, fungi spread much more easily under the concrete filler, usually because when the trunk was hollowed out, the inner partition layer the tree grew to protect its healthy wood was breached. That would be a bit like someone scratching the scab off a wound. Moreover, in rainy weather, the concrete gets soaked and slowly releases the moisture it has absorbed into the interior of the tree. This creates the conditions fungi like best, because it means they can grow undisturbed—directly into the healthy wood. From the outside everything looked great, but in reality, the decay and with it the danger posed by the tree were drastically increased.

TODAY THIS IS usually no longer done. Instead, the tree is put under strict observation. It is inspected regularly to find out how much healthy wood remains and if the tree is sufficiently stable. If it doesn’t pass the test, its crown is carefully shortened to reduce the load the trunk has to support. This allows the tree to stay standing for a few more years. However, shortening branches always comes with its own set of side effects, as you will soon see.

Have you ever seen brutally mutilated street trees? They look as though sadistic tree cutters have had their way with the poor defenseless things. But the real reason they look this way is usually not nearly as interesting. The authorities were saving money. Crown reduction should be done by well-educated and, no less important, tree-loving people.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.