What will happen when an epidemic emerald ash borer outbreak occurs?

Aesthetic impact

Ash Trees Dying from Emerald Ash Borer Infestation
The ultimate result of emerald ash borer infestation is tree death. Once a tree has been infested, the tree declines rapidly over the course of 4-8 years.

Within 3-4 years after initial infestation, trees show significant damage: canopy dieback, sucker growth and bark-splitting are common outward signs of infestation. From this point forward, trees rapidly decline until they have little to no foliage and severe structural damage.

The devastating effects of heavy emerald ash borer pressure are most apparent in the photos from communities where EAB has been present for several years. Tree-lined avenues – once lush and green – have been transformed into stark rows of defoliated dead ash.

EAB in Minneapolis St. Paul

Economic impact

The economic impact of emerald ash borer infestation is substantial. Ash trees provide significant value to our communities:

  • They help reduce heating and cooling costs
  • Increase property values
  • Provide shelter to various forms of wildlife
  • Help reduce storm water run-off.

The loss of these benefits is immediately cost-prohibitive and can affect the economic vitality of a community for years. In addition, dead and dying trees pose safety hazards that require extra funds for managing.

These costs, combined with the costs of large-scale ash tree removal, can be astronomical. Many municipalities severely affected by emerald ash borer have already spent millions of dollars cleaning up after the pest.

Metro Wide Ecological Impacts Trees Produce

  • CO2 emission reductions due to energy Savings and sequestration by street trees are 27,611 And 29,526 tons, respectively, valued at $857,000 ($4.31 per tree). (2,012 tons – $30,175).
  • Net CO2 reduction is 55,125 tons, valued at $826,875 or $4.16 per tree.
  • Electricity saved annually in Minneapolis from both shading and climate effects of street trees totals 32,921 Mega Watt Hour, for a retail savings of $2.5 million ($12.58 per tree).
  • Annual savings of natural gas total 441,355 MBTU, for a savings of $4.3 million or $21.78 per tree annually.
  • Total annual energy savings are valued at $6.8 million or $34.36 per tree.
  • Net air pollutants removed, released, and avoided averaged 2 lbs. per tree and are valued at $1.1 million annually or $5.71 per tree.
  • Avoided emissions of NO2 and SO2 due to energy savings are especially important, totaling about 150 tons and valued at $830,000 deposition and interception of pollutants by trees totaled 29 tons ($185,585), a small benefit explained by the region’s relatively clean air.
  • The ability of Minneapolis’s municipal trees to intercept rain—thereby reducing storm water runoff is substantial, estimated at 447.5 million cubic feet annually, or $9.1 million. Citywide, the average street tree intercepts 1,685 gallons of storm water valued at $45.67, annually per tree.
  • The estimated annual benefits associated with aesthetics,property value increases, and other less tangible benefits are approximately $7.1 million or $36 per tree.
  • Minneapolis has invested millions in its urban forest. Citizens are now receiving a substantial return on that investment $1.59 in benefits for every $1 spent on tree.
  • As the urban forest resource matures, continued investment in management is critical to insuring that residents receive a greater return on investment in the future. Starting over with removal of 21% of the urban forest would have severe monetary implications.