Cheshire Arboriculture - Terravention In Context
As a result of a development involving an extension of an old property in Leeds an attractive Copper Beech was damaged.
This involved the tree loosing a portion of its roots to a service trench (next to the footpath, see photo) while on the other side the area was used for access, causing compaction.
Therefore with the expectation that the tree would react badly to these impositions I was contacted by JCA Ltd to undertake terravention to redress the compaction.
Compaction causes anaerobic conditions in soil. Roots need oxygen as well as moisture containing dissolved nutrients and micronutrients so the exclusion of oxygen will damage or even kill tree roots.
The other effect of compaction is to damage the soil ecology and as soil itself is like a living organism. Anything that damages the number of species and the species density, also damages the fertility of the soil.
In such circumstances even the presence of a layer of grass beneath the tree can be significant competition for the tree
What was needed was an immediate intervention to reverse the compaction and improve the soil.
The Terravent was able to redress these immediate problems by decompacting using a burst of Nitrogen Gas, then injecting the ground with a solution containing Mycorhizal fungi before infusing the injected solution throughout the network of cracks using a second burst of gas.
But the next part of the solution is to improve the soil in a fundamental way. This was achieved by introducing an animal that can maintain the areation and fertility of the soil. We introduced Worms.
The two varieties we chose were Lumbriscus terrestris, a large deep living variety that we released into the Terravent probe holes, and Eisenia hortensis, a vigorous smaller animal that lives in higher densities in the surface layers. The Eisenia were broadcast in much greater numbers.
These worms however needed both a worm friendly medium in which to live, and food. These needs were met by distributing approx 6 cubic metres of well composted woodchip mulch in a 100mm layer over the area that we Terravented.
Coincidentaly the mulch will remove the competition from the grass, discourage foot traffic and help to stop sunlight acting directly on the soil as that would heat and dessicate exposed upper layers and further damage soil ecology.
Without these further measures many of the benefits from one application of the Terravent are reversible.
We consider this enhaced specification to be a self sustaining holistic solution to compaction and root damage in which decompacting with the Terravent is just one component.