Boxwood blight continues to spread

Samples of boxwood infected with the fungus Cylindrocladium pseudonaviculatum, the cause of boxwood blight, were confirmed by the Rutgers Plant Diagnostic Laboratory and the New Jersey Department of Agriculture Laboratory in July. This was the first report of the disease is New Jersey.

Earlier in the summer, boxwood blight was confirmed in a retail nursery in Delaware.

The latest reports bring the total number of states with confirmed findings to 12 (CT, DE, MA, MD, NC, NJ, NY, OH, OR, PA, RI, VA).

Initial symptoms of boxwood blight appear as light brown spots on the leaves. Spots enlarge, often with concentric circles or a zonate appearance, until entire leaves are blighted and shed. The fungus also infects woody tissues, which results in dark brown to black “diamond-shaped” lesions and stem dieback. Defoliation and stem dieback are rapid. Be aware that boxwood blight spreads very quickly in warm and humid conditions and has the potential to do significant damage to your plantings, said Richard Buckley of Rutgers Cooperative Extension.

For comprehensive information on boxwood blight, visit www.boxwoodblight.org.

Photos by Sabrina Tirpak, Rutgers