The felling of trees that the Community of Madrid is carrying out in several areas of the capital, due to the expansion works on Metro line 11, has been met with frontal opposition from neighborhood groups, environmental groups and the central government. .
At the beginning of December last year, with the authorization of the City Council, the felling of the 523 trees affected by the works in Madrid Río and Comillas Park began.
The same fate is facing 29 specimens, among cedars and shady plane trees, from the garden of Jimena Quirós, next to the Atocha Station, an area included in the Landscape of Light, declared a UNESCO World Heritage Site.
Voices opposed to these measures propose alternatives to the radical elimination of trees, such as changing the layout, excavating the tunnels in a mine (as opposed to the chosen one, in the open sky) or transplanting the specimens in question.
This last option is the one defended by the Ministry of Transport for the works of the new Atocha through station that will connect the high-speed tunnel between Puerta de Atocha-Almudena Grandes and Chamartín-Clara Campoamor with the new high-speed southern access.
According to Adif, its plan allows all the trees around the new infrastructure to be protected and transplanted, except for one.
Specifically, it has planned the protection of 147 specimens and the transplant of 231 in soils close to the action, "through the most viable techniques for each tree, taking into account its conditions and uniqueness."
This option is not without complications.
In the opinion of Carlos Calderón, PhD in forestry engineering from the Polytechnic University of Madrid and professor of the master's degree in gardening and landscaping, “the transplant of large urban tree specimens should be one of the last alternatives and should not become an administrative instrument that calms consciences, without taking into account technical criteria that determine whether this transplant has any future.”
According to Calderón, the transplant is viable and there have been many cases of success, “as long as it is planned properly and the circumstances allow it.”
In this sense, he explains that a series of previous tasks must be carried out that, in some cases, have to begin months in advance and thus prepare the tree for that traumatic phase that it is going to suffer.
Among other operations, “a crown reduction would have to be made to compensate for the future reduction of its roots.”
If these phases are not met or the physiological state of the tree is not adequate, the survival percentage decreases, says the engineer.
A younger tree
The majority of the trees affected by the Madrid metro works, both in Atocha and in Madrid Río and Comillas, are plane trees (
Platanus × hispanica
), a predominant species also in the entire city of Madrid, with more than 100,000 specimens, according to data provided by the teacher.
The resistance of this species to environmental alterations, drought, pruning and, in general, to the urban environment, means a certain initial advantage when evaluating its transplant.
However, as the forestry engineer explains, it is likely that some individuals may be affected by anthracnose (a disease caused by a fungus), present cavities or rot.
Furthermore, in his opinion, when they are already of a certain age and size, like some of the specimens in question, "it is worth asking whether it is worth it in the long term to carry out this transplant or opt for its replacement."
“A mature shade plane tree, close to 60 years old, subjected to moderate pruning throughout its life, has already produced all the wood it can generate to fix carbon, while 60 young trees replacing one adult would have greater storage potential in the medium or long term,” says the expert.
Cedar, for its part, is one of the most recommended species for capturing and retaining atmospheric pollutants.
As Carlos Calderón explains, its perennial nature, added to the arrangement of its needles (needle-shaped leaves), make it “very effective in trapping suspended particles that are also retained by the sticky substances that its leaves have.”
Transplanting conifers, a group to which the Himalayan cedars (
Cedrus deodara
) felled in Atocha belong, is even more complicated.
Size and age, which could range between 60 years and 75 years, in the opinion of this expert, “play quite a bit against them.
The older you are and the larger the size of the foot to be transplanted, the more difficult it will be to overcome it.”
Furthermore, if the main branches are eliminated, as a necessary preliminary step, "their size would never be recovered, since conifers do not resprout after pruning, so transplants, unfortunately, would be quite likely to fail."
Furthermore, the operation in this species is complicated because its taproots tend to go deeper, the same reason why the alternative of excavation in a mine should be considered with caution as it increases the risk of overturning of the trees due to the alteration of their drainage system. anchorage.
The other key to the success of transplants, according to Professor Calderón, is their own execution: “When it is performed, the meteorological values on those days, the duration of the operation, the distance and the care during transportation, the peculiarities of the destination place, the climate and the surveillance in the months and years after the transplant.”
Porting and rooting
As technical difficulties increase, economic costs also grow exponentially.
Calderón, author of the thesis
Urban trees and atmospheric pollutants in big cities: Effects in Madrid,
in which he studied all the public management trees in Madrid for nine years – which includes the alignment, the park and gardens, peri-urban parks and the green areas of National Heritage–, the question arises “if it is no longer worth using the cost of these transplants to carry out a new plantation of young trees, fixers of atmospheric pollutants and with a long life ahead, while improving the conditions of the rest of the existing trees.”
However, this replacement "brings with it a loss of heritage, landscape, social and emotional value related to the existing mature trees, as well as a decrease in environmental quality derived from the decrease in shade and the consequent increase in temperature in the area." of influence of each adult tree felled,” he acknowledges.
With its almost six million trees, Madrid was recognized last March as 'Tree City of the World' for the fourth consecutive year.
Carlos Calderón clarifies that, with its nearly three million copies under public maintenance and management, “the capital is in an honorable position among the 10 greenest cities on the planet,” and that entails a large amount of resources that, in its opinion, they should be even higher.
As the main problems of tree management in Madrid, Professor Calderón points out the disproportionate pruning carried out in previous decades that has generated abnormal growth and rooting, the use of some species that are not suitable for the space available on sidewalks, the reduction of tree pits, multiple works and ditches that are carried out or the abusive use of only six main species, which represent close to 80% of the total.
In his opinion, this has contributed, among other causes, to the premature aging of the capital's trees.
The expert considers that greater awareness is necessary regarding respect for urban trees to prevent deaths related to cardiorespiratory health due to pollution and heat episodes.
“This same interest should be given every day and to all trees and not only for eventual circumstances that have little to do with a long-term plan to improve and renew existing trees,” says Calderón.
You can follow ICON on
,
X
,
, or subscribe to the
Newsletter here
.
Subscribe to continue reading
Read without limits
Keep reading
I am already a subscriber
_