Urban Forestry: Hazard Management

Tree Hazard Management in an Urban Forest

Urban Forestry: Hazard Management

Trees growing in an urban forest are very different from trees growing in a natural forest. Urban forests are planned and maintained with human benefits in mind. We plant trees for beauty, food, shade, and privacy. Sometimes we plant trees that are not well suited for our environment, or that will grow too large for the space provided. Many trees have vastly decreased lifespans in an urban vs. a natural environment. Because of this, we must actively nurture and maintain urban trees in ways that trees in nature would never require. In nature, trees ‘self-prune’; as limbs grow old or become less useful, they are dropped. In an urban environment, this same process could be hazardous. Fungi can infect ‘wild’ trees, become hollow and fall over, in your backyard this same process would most definitely be hazardous!
Here are important, responsible steps for a homeowner to take to mitigate liability and hazardous situations:

  • Cultural Care: Soil maintenance, fertilization/re-mineralization, and irrigation should be species and climate appropriate. Poor cultural care is the source for most tree health issues.

  • Health and Hazard Assessment: Trees should be assessed for overall health (just like you, your kids, or your pets!) Hazards should be evaluated and monitored. All evaluations should be performed by a Certified Arborist.

  • Treatment: Pest infestations should be diagnosed and treated early to prevent severe health consequences.

  • Trimming: Depending on the species, most trees should be trimmed every 1-3 years to open the canopy for air flow and remove hazards. NEVER TOP YOUR TREES, or you will pay the price later. 
  • Protection: Trees should be protected during all construction by having an Arborist set up a Tree Protection Zone (TPZ), and the tree should be inspected during and after construction.

  • Removal: Trees do get old, old trees are susceptible to heartwood rot leading to hollow, unstable trees. Old trees should be removed if they become hazardous.