Cutting Tree Roots Impact provides more information about the impact of cutting tree roots on large trees, which is subtle but real. As Parker continues to develop new areas, tree root loss will be a persistent issue.

“The effect of the stress of the trees can take from 3-6 years to manifest,” according to the article from American Grove cited below. The growth of optical fiber and cable added miles of new trenching and damaged roots.

“When urban areas are trenched, urban tree roots are often cut and or mangled. Loss of roots directly correlates to less water absorption which entails a drop in photosynthesis, transpiration, and carbon assimilation.”


tree roots, showing extended dripline and typical depth
While prevention is the best cure, the author suggests having a map of an irrigation installation that minimizes root damage. Applications such as mycorrhizae treatments after the roots have been cut is doable –  but not desirable.

Loss of water absorption is the biggest factor in causing early decline.

In the interview with Dr. Alessio Fini,  he says they used infrared technology to see what was happening in the tree with severed roots. The structure that transfers water from roots to branches showed a drastic reduction in photosynthesis even when the tree seemed perfectly healthy.  He talks about a scale of 3 to 6 years that show inner decline before outer symptoms appear.

Even during times of heavy rain, trees with severed roots still showed signs of drought stress. In a situation where an arborist is called to improve the health of a tree with roots cut, “it’s usually too late”, Dr. Fini said.

But there are a few methods to help keep the tree alive.

  • Irrigation or watering the tree
  • Improving soil moisture
  • Using treatments to grow new roots, specifically feeder roots

Sources:

Root Severance on Trees – American Grove

Arborviews interview with Dr. Alessio Fini – ISA