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Reducing runoff

reducing runoff diagram
A trencher can be used to dig four or more trenches out from the planting hole. Loosely fill the trenches with the same soil that came out of the trench, or amend it with organic matter if you wish. This provides loosened soil channels for root growth in a compacted site. Vertical trenches can be cut along a slope to slow runoff water.

Trenches dug into the soil profile can also improve drainage (figure on right). Water collects in the loosened soil in the trench and infiltrates into the soil profile instead of running off. Creating terraces with retaining walls helps to level a site allowing water to percolate through soil instead of running off.

Trees planted in soil retained by a wall should be appropriately sized. Large trees, especially those with aggressive roots should not be planted here unless the tree is at least 10 feet from the wall. Small and medium-maturing trees can be planted closer.