The movement of equipment and the storage of materials on a construction site can compact the soils, resulting in major changes in the soil air and water characteristics. This results in possible damage to existing plant roots and fewer and smaller pores in the compacted soil layer.
Compaction commonly results in water moving into and through the soil more slowly.
Surface runoff and erosion are increased. Less water moves into the soil to become available for absorption by tree roots, and soil aeration may be reduced. Plant roots also often have more difficulty growing in and through compacted soil since they grow through pore spaces in the soil. Because soil compaction is extremely difficult, expensive, and often impractical to correct once it has occurred, the emphasis is on prevention. While it may not be practical to eliminate compaction from a construction site, a number of things can and should be done to minimize its impact on trees.