Urban tree concept Koblenz Concept for the development of a long-term healthy urban tree population

The urban tree concept was developed as a new planning instrument for the preservation, renewal and expansion of the urban tree population and applied for the first time in the city of Koblenz. It is a practical guideline for action, which on the one hand prepares a safeguarding and coordination of measures for the greening of the built-up urban area with the political and socially responsible parties up to those affected. On the other hand, it provides planning and project sponsors with binding guidelines in connection with tree planting. The urban tree concept includes several planning levels: from a framework planning covering the entire urban area, to a district-related structural planning, to a detailed location-related planning of measures.

The aim of the urban tree concept, which is based on urban ecological and design principles, is - under the increasing changes in environmental and climatic conditions - to build up a long-term healthy urban tree population.

In addition to the creation of the best possible structural conditions at the respective tree location, this includes in particular design specifications for the integration of urban trees in the urban space. With the urban tree concept, the necessary planning requirements are created, which are necessary for a greening coordinated with the respective urban situation.

Overall, the task is to create a binding guideline for action for different planning and action levels as well as projects of various kinds (urban land use planning, redevelopment of the traffic and pipeline infrastructure, redevelopment and expansion of the tree population). The concept is to be secured in the political arena. Users are planning and project sponsors in addition to the municipal green administration.

The development is carried out in several stages in self-contained planning.

FUNDAMENTATION: The relevant planning principles (climate, urban space, vegetation) and already developed plans (tree cadastre) are evaluated and criteria for the selection of suitable tree species are determined.

FRAMEWORK PLANNING: Generally applicable design principles as well as guiding principles (e.g. tree planting to strengthen village entrance situations, to highlight cultural-historical elements or for accompanying greening of infrastructures) are fixed for the entire urban area as well as for individual settlement types. At the same time, areas in need of action as well as priorities and execution principles are defined.

STRUCTURAL PLANNING: Measures for the preservation, renewal and development of tree populations are specified. The previously described guiding principles are supplemented with statements regarding design, tree species, and measures to prepare tree locations.

Measure planning: Finally, measures are planned for individual implementation sections. When determining tree locations, functional specifications such as access roads, visual fields at intersections, design and building culture aspects as well as concerns of the network-bound infrastructure (gas, water, electricity lines and sewers) are taken into account.

IMPLEMENTATION: The definition of targeted measures is the essential task of the urban tree concept. In addition to the planning of measures, the guiding principles specified in the course of the framework planning or the results of the structural planning in the course of replanting or also targeted new plantings, enable the conceptual specifications for the long-term ecological and design development of the urban tree population, without great planning effort to ensure.

PRAXISTEST: A planting concept was developed for the southern inner city of Koblenz, which is structured according to a clear ordering principle, taking into account the development function of the individual streets: native tree species such as wood pear and cherries are proposed for all streets leading north to the Moselle, lime trees are proposed for all historically influenced main streets, and non-native tree species such as swamp oak and ginkgo are proposed for new plantings on all streets leading to the Rhine. Based on this, a measure plan was drawn up for Kurfürstenstraße and the planting measure implemented accordingly.