In the end of October, we test lifted and examined a number of trees that will be affected by the construction of the West Link. The purpose was to gain the necessary knowledge to later be able to preserve the trees by relocating them.
The Swedish Transport Administration has been commissioned to build the West Link which, among other things, will affect trees and parks. In order to build the West Link, as well as minimise its impact and ensure that parks and natural environments are restored, our assessment is that the best solution would be to temporarily or permanently relocate certain trees.
In the end of October, we test lifted three trees and examined the roots of an additional number of trees in Kungsparken and at Haga Kyrkoplan. By examining the trees, we will gain more experience and the knowledge needed in order to move the trees at a later date. Archaeologists was also on site to do archaeological inspections, as the area is classified as ancient remains.
In collaboration with specialists
The work with the trees has been carried out in collaboration with the City of Gothenburg, amongst others. They have previously played a part in examining roots and lifting and relocating trees in Gothenburg. Germany is the country where most trees have been relocated, and it is a German company that has been procured to perform the lifts of the trees in Haga. They have many years of experience and relocate between 5,000 and 10,000 trees per year across all of central Europe.
Örjan Stål specialises in issues relating to trees and soil and has worked with tree relocation for around ten years. He is one of the specialists who is helping to preserve trees within the West Link project.
Why must the trees in Haga be examined?
“By performing trial lifts of the trees and examining the roots we gain knowledge about the extension of the root system and the characteristics of the soil. The purpose is to gain more information about the conditions of the area, as well as additional knowledge in order to relocate the trees when the starting date for the West Link build approaches,” explains Örjan.
How are the trees lifted and the roots examined?
“The lifts are carried out using a specially built machine that lifts the trees up with a scoop. Before the trees are put back, the soil and the roots in the cavity are examined. Normally, a trial lift takes around 30 minutes, but if you are carrying out archaeological investigations as well it may take longer.”
“We also examine the root system of some other trees in the area. Then we carefully dig down towards the roots of the trees by removing the soil, layer by layer, with a smaller excavator. By doing so, we can see the extension of the root system, how thick the roots are and what condition they are in. We examine the characteristics of the ground and the soil and take soil samples before we refill the cavity, water the tree and restore the ground.”
Are the trees affected by this?
“After a tree has been lifted from the ground, it puts a lot of energy into restoring the root system. Therefore, it is common for the tree's branches and leaves to show less growth in the following years after a tree has been lifted. When the root system has recovered, the tree's growth returns to normal. A tree lift almost always succeeds when the conditions are good and the trees are in good condition,” concludes Örjan.