What not to do as a landscape architect
Trees and woody shrubs are best planted in the native soil where they are installed. No amendments or fertilization is recommended at the time of planting unless soil testing has revealed a deficiency.
Tree planting pits should be dug no deeper than the depth of the plants' root system, but twice or more the diameter of the root system. Planting into compacted soils on construction sites is the cause of many tree and plant problems. In many cases, landscape soils are simply spread in a thin layer over compacted soil that does not support root growth.
pinker.wjh.harvard.edu
Any method that breaks up the compacted soil, creating pore spaces for air and water and allowing some of the new landscape soil to be incorporated into the disturbed soil, will improve plant survival.
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