Structural soils are used in most parts of the world to extend root growth to soil volumes beneath pavements. Since structural soils were studied first, more than 20 years have passed.

In a conference arranged by the University of Copenhagen, the Swedish Universiy of Agricultural Sciences and the University of Helsinki, assisted by the Norwegian University of Life Sciences, and Bioforsk, Norway and supported by the Nordic Fund for Urban Trees (Nordisk Fond for Bytræer), international experts from science and practice shared knowledge and experiences with structural soils.

Twenty years of Cornell Structural Soil -   growing trees in pavement and parking lots.
Nina Bassuk, Professor, Urban Horticulture Institute, Cornell University, USA.
Where the roots grow: Structural soil excavations in Copenhagen 
Oliver Bühler, Assistant professor, University of Copenhagen, Denmark.
Morten Ingerslev, Senior researcher, University of Copenhagen, Denmark.
Structural soils and urban vegetation: Ideas and challenges suggested from selected research
Jason Grabosky, Professor, Department of Ecology Evolution and Natural Resources, Rutgers University, New Jersey.
12 years of structural soil research in Helsinki, Finland: Viiki Urban Tree Laboratory
12 years of structural soil research in Helsinki, Finland: Tree Growth in structural soils
Anu Riikonen, PhD-fellow , Department of Forest Sciences, University of Helsinki.
Structural soils as storm water magazines – Hornsgatan in Stockholm
Johan Östberg, Researcher, Department of Landscape Architecture, Planning and Management, Swedish University of Agricultural Sciences, Sweden.
Standardized structural soils for urban trees in Germany
Philipp Schönfeld, Head of the working group Plant Ecology and Planting Design, Bavarian State Institute for Viticulture and Horticulture
Structural soils: Research and Examples from Norway
Ingjerd Solfjeld, Senior Engineer,Norwegian Public Roads Administration
22 Years of experience with structural soils in Oslo: What have we learned so far?
Erik Solfjeld,  Urban tree manager, Park section, City of Oslo, Norway.
Plant selection for structural soils
Henrik Sjöman, Post-doc, Cornell University, USA.