Does Extreme Heat Cause Sudden Branch Drop Syndrome?

Sudden Branch Drop Syndrome is when a healthy tree’s branches suddenly fall. It’s a rare phenomenon whose exact cause is unknown and is typically not fatal. But after an oak tree’s limb dropped in Garfield Park on July 10 and resulted in the death of 35-year-old Sarah Noah, officials are considering if extreme heat could have been a contributing factor.

Also referred to as “sudden limb failure,” it usually occurs in the summer, but wind or storms are not considered a factor. Oak trees with large and heavy branches are prone to the syndrome, and the likelihood increases in older trees. Branches tend to break about 3 feet from the tree trunk and the drop can extend about 12 feet. Once a tree experiences Sudden Branch Drop Syndrome, it will likely experience it again.

The tree whose branch fatally struck Noah was about 100 years old, but showed no warning signs, according to the Department of Transportation’s Urban Forestry Division. That tree was taken down that day. The division later identified six trees to be removed because they were deemed dead and no longer growing. DDOT says they will create a management plan for trees labeled “poor.”

Thomas Spencer of the Heart of Wood Tree Service in Arlington told Washingtonian that while it’s difficult to determine if sudden limb failure was the cause of Noah’s death, “the stress on the trees lately has been really, really bad in this area because of the heat.” Oak trees are increasingly dying because they’re not accustomed to the rising temperatures and the D.C. region’s drought.

The Adirondack Tree Services advised customers to avoid activities under trees while the hot weather and drought persist. If you have an oak tree in your backyard or on your street, here’s our guide on when and how to water your tree. The Trees for Georgetown group also has some watering tips; they’re also looking for donations to help continue their maintenance efforts.