Cutting Tree Roots vs. Cutting a Tree Down

Roots

• Most tree roots lie within the top 18 inches of the ground, but about 20 percent of all trees develop heartroot systems that go even deeper, according to the University of Massachusetts. Mature trees always extend a feeder root system well beyond the edge of the canopy. Large buttress roots grip the soil horizontally, stretching and compressing like springs as wind buffets the tree. If heartroots do exist, the only way to remove them involves cutting through buttress and feeder roots and digging. The tree becomes unstable as it loses roots, but even a few deep roots could temporarily hold the tree upright.

Root Damage

• Trees with existing root damage could fall with no warning. Losing half its supporting roots destabilizes a tree, according to the USDA Forest Service. Trees already leaning, with roots on the opposite side that partially lift from the ground, could fall when winds apply the right pressure or when rain softens the ground. Tree roots often extend horizontally for several times the width of the tree's canopy. Feeder roots could lie under buried utility cables, water or sewer mains and sidewalks. Roots ripping loose under the weight of a falling tree could cause damage well away from the tree. An uprooted tree also leaves a large hole behind.

Felling

• A stepped cut accurately fells a stable tree without doing damage above or below ground. A horizontal notch one-third the trunk diameter deep, on the side facing the direction of fall, creates the front of the cut. Cutting on the opposite side of the tree, a few inches above and stopping just short of the first cut, severs the trunk but leaves a "hinge" section to control the fall. Only experienced professionals should remove hazardous trees that lean toward buildings, other trees or utilities. Some situations require tree removal in sections, working in stages from a power lift.

Stumps

• Chainsaws can cut stumps back to only a few inches above ground level. The remaining wood could stay in place for many years as it rots. Stump-removing chemicals accelerate that decomposition. Cutting old roots around a rotted stump could loosen it enough to pry loose and winch out. Gas-powered stump grinders chew a fresh stump into chips, taking the wood down slightly below ground level. After cleaning up the chips, a layer of dirt hides the remains. The buried stump still creates a long-lasting scar of infertile ground, and a hole forms as the wood gradually decays.