Prof Dr Frank LOHRBERG

Institution: Chair of Landscape Architecture, RWTH Aachen University – Germany

About: born in 1964, Prof Dr Lohrberg studied landscape architecture at Hanover University and won the Peter Joseph Lenné Award in 1990. Beginning in 1994, he worked at the University of Stuttgart where he received his doctorate in 2001, which dealt with urban agriculture and city planning. Since 2002 he is principal of Lohrberg Stadtlandschaftsarchitektur, the office focuses on landscape architecture. In 2010, he was appointed as chair of the Institute of Landscape Architecture at RWTH Aachen University. Prof Lohrberg is member of the German Werkbund, the German Association of Landscape Architects and the German Chamber of Architects. He was admitted into the German Association of Town Planning and Regional Planning in 2009.


Keywords: Urban Forestry, Landscape Laboratory, Productive Landscape, Action Research, Co-design

Cologne’s spatial structure has been defined by its 1920ties Green Belt, initiated by, the then mayor, Konrad Adenauer and designed by urban planner Fritz Schumacher. The Green Belt is characterised by large woods framing a linear open space dedicated to recreational, social and aesthetic functions. In 2010, adjacent to this prominent feature and a noisy motorway, the City of Cologne and its sponsors created the “Waldlabor Köln” to test new forms of urban forestry, greatly inspired by the landscape laboratory in Alnarp, Sweden. This introduction will explain the short history of the Waldlabor, its four components and general layout.

The most intensively managed section since its development, has been the “Energy Forest” (1), where fast growing trees, mainly poplars and willows have been cultivated for sustainable energy production. Plantations are harvested every 3-5 years leading to abrupt changes in the landscape; but how have people reacted? Have they accepted this harvesting? A research project funded by the federal state of North Rhine-Westphalia provided some initial answers; it became obvious that the Waldlabor should promote its aims more clearly. To this end RWTH Aachen University conducted a workshop in 2016 allowing students to modify the forest through cutting, pruning and trimming the trees. The one-week interventions resulted in inspiring designs which shed light on hidden functional and aesthetic values of the forest.

Meanwhile other parts of the Waldlabor have also thrived and were selected as the setting for a follow on Waldlabor workshop with students in 2018. The “People’s Forest” (2) aims to introduce experimental compositions of trees which will create new aesthetic experiences based upon contrasting bark colours, autumn foliage and leaf shapes. The trees planted have been individually sponsored by local citizens. The “Climate Forest” (3) consists of 6 compartments which spread out across the area. Each compartment comprises of just one tree species, creating a unique spectacle. Trees such as Quercus pubescens or Sorbus aria were chosen to test their adaptability to climate change within an urban setting. The Wilderness Forest (4) is a ‘control group’; this area has been left to develop naturally, and will illustrate the effects of non-intervention and potential wilderness qualities.

The whole site has been designed as a public space. Paths meander through the area and various signs explain the Waldlabor concept. Now ten years’ old, the Waldlabor is well established as a unique component of the Cologne Green Belt. However, research still continues; as the trees grow, experiments are developing new knowledge and perspectives on the future of the Waldlabor. Hence, there is now a need to refocus its aims and methodologies for the next decade.

Presentation: link