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Apr 12 / 21 Forming Macro Aggregates to Break up Soil Compaction

We thought we would post a quick share on an easy method to break up soil compaction. From our investigations across Canada, it is one of the top 3 challenges urban forestry is facing every season. Although compaction is essential to the stability and longevity of all roads and sidewalks, for root establishment, it’s a real hindrance. This puts a priority on addressing compaction issues around street and boulevard trees in manufactured landscapes. This usually requires inputs of not just quality soils, but amendments that will continue to work to release the beneficial properties within those soils. The Biological, Chemical and Geological properties that compose the foundation of every ecosystem.

A Focus on Soil Chemistry

One non-mechanical method to relieve compaction where we have seen significant results is the addition of humic substances. This aids in forming micro and macroaggregates from the silt and clay particles in soils. The practice of adding humic acid complexes with ions such as Mg2+, Ca2+, Fe2+, and Fe3+ that are commonly found in the environment creating humic colloids. These colloids bind soil particles together through their positive and negative charges and create larger aggregates to allow greater water and air infiltration.

For clarification, it’s not that the roots can’t penetrate clay and rocky soils, it’s the anaerobic conditions of microbial decomposition of organic matter creating fermented alcohols. Once tree roots reach these conditions they can not penetrate through this layer and will grow horizontally or upward until they reach suitable conditions. Without vertical roots, juvenile trees will have a rough time making it past the 3-year mark. This makes them prone to drought, weak branches, and blowdown.

References:  1) Journal of Environmental Management 117 (2013) 85e95. Remediation to improve infiltration into compact soils.  2)Science of The Total Environment, Volume 586, 15 May 2017, Pages 807-816


We do mineral and biological analysis! It never hurts to know where you’re winning and what areas may need improvement.  

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