Mayor Deputy Barbara Unterkofler and Wolfgang Seiwald (Head of Municipal Tree Care), Source: Alexander Killer via the City of Salzburg

Salzburg deploys water bags to help trees through the heatwave

Salzburg deploys water bags to help trees through the heatwave

The bags will help protect young trees’ roots from the urban drought

As the heatwave rages on and drought settles across Europe, high temperatures promise to cause problems not only for humans but also for the environment. This is why today authorities in Salzburg announced that they will install water bags on younger trees in the city.

The bags are supposed to keep the roots moist for longer periods of time and ensure that they do not suffer damage from the excess heat. Cities are natural heat islands due to the negative building to green space ratio and tend to accrue much higher temperatures than the surrounding countryside. This makes urban greenery, especially outside of parks, particularly vulnerable to summer weather stress.

Bag them and soak them

Salzburg’s water bags represent bags of soil wrapped around the trunk of young trees. Park authorities will water the soil almost to an excess, which will allow trees to feed off the cool moisture for much longer than if they watered the ground directly.

According to a statement by the city, trees would be able to feed off the water for around a day, which, they have said, saves on watering costs for the city. Also, the bag would help to protect the trunk from injury, tree vandalism and mechanical damage.

The water bags will help keep tree roots hydrated and prevent wastage. Furthermore, the fact most of the moisture is not deposited at the trunk would help protect the tree from rot, due to overwatering.

Deputy Mayor Barbara Unterkofler, responsible for the city’s green spaces, was quoted in a press release, explaining: “Every tree in the city has a positive effect on the city climate and the well-being of the people and increases the quality of stay on site. It is particularly important to me that the tree plantings are sustainable.”



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