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El Ayuntamiento aplicará un plan de actuación con técnicas de descompactación, enriquecimiento del terreno y siembra de especies adaptadas

The Vitoria-Gasteiz City Council has presented the results of a comprehensive study on the quality of soils in parks and gardens in the city. The report, pioneering in its scope and level of detail, responds to the growing concern about the deterioration of urban tree cover, which in recent years has shown signs of weakening, such as loss of foliage, withered leaves, and reduced growth. In some cases, this situation has led to the death of specimens.

«Soil is often overlooked in urban management, but its role is fundamental,» highlighted the Councilor for Public Space and Districts, Beatriz Artolazabal, during the presentation. «If we want healthy trees, we must first ensure they have a living, fertile, and well-structured soil. This study has given us a clear diagnosis, and now we will apply the appropriate treatment,» she added.

The study analyzed soils in 16 green spaces in the city, including parks like Arriaga, Olarizu, La Florida, El Prado, Judimendi, Gazalbide, and San Martín. Drillings of up to 60 centimeters were carried out to collect samples that were evaluated from a triple perspective: physical, chemical, and biological.

The soil compaction emerges as the most serious problem. «Just like a sponge, soil needs pores for air, water, and nutrients to circulate. But when it is heavily trodden or vehicles pass over it, those pores disappear, the soil hardens, and the roots cannot breathe or feed,» explained Artolazabal.

In addition, the soils show limited microbial life, nutritional deficiencies, and, in some cases, the presence of inappropriate materials like rubble. This situation directly affects the condition of the tree cover, which in many areas has lost vigor or shows signs of accelerated aging.

«Climate change is also exacerbating this situation. Summers are drier and warmer, and our soils, already clayey, crack and harden even more. That’s why acting now is urgent,» emphasized the councilor.

Action Plan in Progress

Faced with this reality, the City Council will launch a comprehensive intervention plan to restore soil health in urban parks. The plan includes five main lines of action:

Mechanical decompaction of the soil using specialized machinery, without damaging the roots, and subsequent filling with compost and sand.
Organic matter input to stimulate microbial life, improve soil structure, and enhance water retention capacity.
Correction of nutritional deficiencies, especially in new plantations, with root fortifiers and organic fertilizers.
Planting of adapted species with deep roots that help naturally decompact the soil.
Monitoring and follow-up in the medium and long term to assess the effects of the measures applied and plan new annual actions.

Artolazabal has announced that this year the City Council will tender a specific contract to systematically start these decompaction works, with an annual investment of 32,000 euros. Additionally, in an initial approach, 26,000 euros will be invested in planting and 30,000 euros in nutrient application. «We have the resources and the technical knowledge. And, above all, we have a clear vision: protecting our trees is protecting our quality of life,» she affirmed.

The goal, emphasized the municipal official, is clear: to ensure that the public continues to enjoy vibrant, healthy, and resilient parks, capable of providing shade, biodiversity, and well-being. «Trees take care of us. It is our duty to take care of them as well,» she stated.

Presentation of the appearance (PDF)