Iowans lost an estimated $20 million in annual benefits from urban tree canopy damaged by the hurricane-strength derecho in August 2020, according to the results of a recently completed survey conducted by the Iowa Department of Natural Resources.
Findings were included in a report, available online at https://www.iowadnr.gov/Portals/idnr/uploads/forestry/DerechoReport.pdf, which estimated nearly 4.5 million trees were damaged or destroyed by the storm in urban areas.
The survey also estimated nearly 2.7 million trees were damaged or destroyed by the storm in rural areas. Those findings are included in a report available online at https://www.mdpi.com/1999-4907/12/5/555.
According to the reports, the Aug. 10, 2020, derecho impacted 27 counties along the U.S. Hwy. 30 corridor.
Sustained winds of 70 miles per hour (mph) lasted nearly an hour over a large swath of central and eastern Iowa, with wind gusts of 110 to 140 mph in portions of five Iowa counties.
The strongest estimated wind speeds in the vicinity of Cedar Rapids were among the highest wind speeds ever recorded during a derecho, peaking at about 140 mph, according to the National Oceanic and Atmospheric Administration.
An aerial survey showed Linn County, where Cedar Rapids is located, had the highest estimated number of trees damaged, at 953,224.
That number might be low, as estimates have put the tree loss in Cedar Rapids alone at 700,000 trees.
The storm damaged an estimated 7,061 acres of tree canopy in Linn County, according to the report.
Polk County, where Des Moines is located, had the second highest estimated number of trees lost, at 642,348, with 4,758 estimated acres of tree canopy damaged.