It rained recently. But March has been unusually dry so far. The government of Upper Bavaria has ordered observation flights to detect fires in the dried-up area early and issued warnings to behave responsibly in nature. Nevertheless, a harvested field recently burned down in Garching and firefighters had to put out a forest fire in Ottobrunn. With World Water Day this Tuesday, March 22, the United Nations is once again drawing attention to the fact that water is the basis of all life on earth. And many in the district of Munich look up at the sky with concern and wonder whether another dry spring is imminent with serious consequences.
When nature wakes up after winter, the water balance plays a major role. Snowmelt brings moisture to the soil. But what about now? The forest farmers’ association in Wolfratshausen, which also includes forest farmers in the Sauerlach area, wrote in February: “2022? We hope for a wet and cool ‘forest owner/forester spring'”. And now there are indications that the forests could suffer from water shortages, as they did in the dry summers of 2015, 2018 and 2019. The precipitation stations of the State Office for the Environment show that it rained far too little in the months from January to March.
Climate change is quickly cited as the reason for the drought. Florian Loher from the forest owners’ association describes the weather situation: “There was less snow and rain this year. In addition, a very dry, continental wind from the east – one speaks of an easterly wind situation – blows quietly over the surfaces and draws the last moisture out of the trees.” He hopes for two to three days of heavy rain. That would be ideal for the planting season that is coming up now. Many forest farmers have already postponed the ordering of the young plants by a week in the hope of rain. In May, when the trees sprout, they absolutely need moisture.
Julia Borasch is worried that the bark beetle will make it big again.
(Photo: Florian Peljak)
Forester Julia Borasch from the Aschheim forest district is out and about in the forest almost every day. She has been responsible for 50,000 hectares of private and municipal forest in the area from Unterschleißheim to Grasbrunn for two years and is also concerned about forecasts that April will also be very dry in March. Old trees are then threatened by the bark beetle, whose season will soon begin. Borasch’s boss, Klaas Wellhausen, head of the lower forest authority at the Ebersberg Office for Food, Agriculture and Forestry, says about the bark beetle: “It feeds on the bast under the bark and thus cuts through the waterways of the tree. Then the spruce trees die. It’s warm , grow up to three bark beetle generations per year.”
Young plants also have difficult starting conditions when the soil is dry. You can irrigate them individually, for which there are state subsidies, says Borasch. In the past two years, she has not had to submit a grant application. However, game also affects the young trees, biting into their bark, which endangers the trees. Especially when they are harder to cure and close their wounds due to lack of water. In order for them to “grow out of the carcass”, i.e. to gain a height where they can bite, they would be surrounded with a specific coat of paint or a fence. However: “It takes about ten years for a beech tree to be sufficiently resistant to all rigors,” says Borasch.
Climate-stable forests
The foresters are convinced that the long-term path is to build more climate-stable mixed forests, including in private forests. The forest farmers’ associations offer training courses for their members. In the Munich gravel plain, beeches are then planted between standing spruces, in the shade of which they thrive. Oaks can develop in open spaces and firs, as alternative trees, complete the range of forest conversion measures.
But even then, the forest stock would be threatened by careless people who throw away cigarettes, for example. The fire in Ottobrunn, to which 750 square meters of forest fell victim, was not caused by the still wanted fire devil from the east of Munich, confirms Martin Huber from the fire brigade press office. He thinks, however, that human reason tells you not to throw away butts or glass in the forest or on dry grass.
More rain would help overall – including the water table. It hasn’t dropped significantly yet. However, “both the upper floor, the gravel of the Munich gravel plain, and the deep groundwater would have very low water levels almost continuously,” explains Christian Leeb, head of the Munich Water Management Office. Alois Bachmann from the Höhenkirchen-Siegertsbrunn waterworks says that nobody needs to worry about the groundwater level in their community, especially since fluctuations are normal, as the statistics from January 2017 to September 2021 show. Despite all this, it makes a lot of sense to save water, not only for forests and animals, but especially for future generations.