Open AccessA New Urban Tree Soil to Safely Increase Rooting Volumes Under Sidewalks
Author(s) -
Jason Grabosky,
Nina L. Bassuk
Publication year - 1995
Publication title -
arboriculture and urban forestry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.222
H-Index - 47
eISSN - 2155-0778
pISSN - 1935-5297
DOI - 10.48044/jauf.1995.030
Subject(s) - loam , compaction , soil compaction , usable , tree (set theory) , mixing (physics) , matrix (chemical analysis) , environmental science , geotechnical engineering , soil water , agricultural engineering , soil science , mathematics , materials science , geology , engineering , computer science , composite material , mathematical analysis , physics , quantum mechanics , world wide web
Soil compaction, which is necessary to safely support sidewalks and pavement, conflicts with urban trees' need for usable rooting space to support healthy tree growth. We have defined a rigid soil medium that will safely bear loads required by engineering standards yet still allow for rapid root exploration and growth. This was accomplished by forming a stone matrix and suspending soil within the matrix pores with the assistance of a hydrogel gluing agent. Initial studies using three stone types and various stone to soil ratios showed that the compacted stone-soil test medium (dry densities > 1700 kg/m3) increased root growth by a minimum of 320% over the compacted clay loam control (dry density of 1378 kg/m3). The proposed system can safely bear load demonstrated by California Bearing Ratios consistently exceeding 40. Discussion of a critical mixing ratio is presented as an approach for developing a specification for field installation.