Juglans mandshurica - Manchurian walnut
Claudia Hartl: "Trees are storytellers!"
The 24-year-old geographer Dr Claudia Hartl works as a dendrochronologist or, more simply, as a tree ring researcher. The tree ring width of trees, which is what we are talking about here, stands for their vitality. It shows whether a tree was doing well or poorly at a given time - for example, whether it was struggling with drought stress, a rise in temperature or with other trees in its environment.
For example, as part of a routine check of conifers in northern Norway, Claudia Hartl's research group discovered in 2018 that the trees had not grown in the 1940s. The story behind this discovery is as incredible as it is fascinating: During World War 2, the German battleship "Tirpitz" had been hidden here from Allied bombers and shrouded in toxic fog for camouflage purposes. It was a nuisance to the trees.
The path to this exceptional research work was initiated and accompanied by the Weihenstephan-Triesdorf University of Applied Sciences: After studying geography in Regensburg, Claudia Hartl did her doctorate at the Technical University of Munich and, during this time, worked for HSWT on her first project on tree ring research. "The time in Weihenstephan was the best part of my education. I felt super comfortable, the colleagues were nice, the lab was well equipped, I could work very independently, and my performance was appreciated," says the likeable "tree researcher" from the Bavarian Forest. That is also where her enthusiasm for trees originated: "Forests, trees and wood - that's what I grew up with! Even as a child, she says, she learned from her grandfather to build a wooden wall and to respect the tree not only as a raw material.
For her diploma thesis, Claudia Hartl reconstructed the moorland ecology of a stretch of land near Regensburg. In her dissertation, she studied the reaction of mountain forests to climate change. In contrast to findings from and about the past, however, she is interested in the present in her current work as an independent scientist in Mainz. "I want to contribute to being able to recognise what is going on today to be able to make perspective recommendations for the future," says the researcher, explaining her approach, which is one hundred per cent in line with the Arboretum's scientific claim.
So, it's no surprise that Claudia Hartl wins the HSWT raffle tree. She had discovered a call from the university on Instagram and answered the question about the qualities of a tree against the background of her research work. Because for her, trees are, above all, storytellers. To elicit their secrets, she uses a hollow drill to extract an approximately 0.5 cm wide core to grind and prepare for her investigations. What will her sponsor tree, a Manchurian walnut (Juglans mandshurica), tell her in 50 years?
Distribution: North-east China, eastern Russia, Manchuria.
Size: 15 to 20 metres high
Leaves: imparipinnate, 45 - 60 cm, with 11 to 19 leaflets
Flower: inconspicuous flowers, green catkins
Fruit: elongated, elliptical nut
