To the editor:
On Feb. 12, the Arlington County Civic Federation presented an informational webinar on Arlington’s tree canopy.
Karen Firehock, director of the highly-respected Green Infrastructure Center in Virginia, explained the science behind a new assessment based on National Agricultural Imagery Program infrared bands and LiDAR light detection that determines the heights of vegetation.
At slide 10, Firehock quietly delivered a bombshell.
First, a little context. In 2016, advocates urged the county government to update its 2011 survey (conducting surveys every three to five years is considered a best practice). In 2017, the county issued a survey – which didn’t use LiDAR – that concluded: “With a current tree canopy percentage of 41 percent, Arlington appears to be staying constant with overall tree canopy, compared to 2011 (40%).”
“Constant,” unless you have eyes to see. Every corner of the county reveals a decline in trees and an increase in buildings and paved surfaces.
All of which Dr. Firehock confirmed on slide 10: “Arlington’s tree canopy is 31 percent, based on imagery that was flown in 2021 and processed by GIC in fall 2022.” That’s 7 points below than in the 2017 study, which used 2016 data.
In sum, in roughly six years, canopy declined significantly. This flies in the face of surveys without LiDAR and claims by some leaders that canopy was increasing.
Kudos to the Civic Federation and the GIC for this eye-opening update which can play a vital role in the first Forestry and Natural Resources Plan (FNRP). The draft FNRP should reflect this sharp downward trend and provide specifics to address the crisis: who will do what, on what timelines, equipped with which resources?
In the face of climate change, too, this is no time to settle for a FNRP flush with aspirations and void of accountability.
Let’s not be blinded. Let the latest statistics on tree canopy speak for the trees.
Kit Norland, Arlington
