A recent report from the North Carolina State University Cooperative Extension showed considerable variability in the susceptibility of Boxwoods (Buxus
spp.) to Boxwood Blight (Cylindrocladium pseudonaviculatum
). The researchers evaluated twenty-four varieties and found B. sempervirens
‘Suffruticosa’ to be the most susceptible. Unfortunately, Suffruticosa (Common Boxwood or English Boxwood) is the mostly commonly planted Boxwood variety in the United States. However, the authors did find nine varieties that, they determined, were “moderately tolerant” to “tolerant” with the most tolerant being B. microphylla var. japonica
Boxwood Blight is a recently introduced plant pathogen in the North America, first confirmed in October of 2011. The disease can cause significant leaf drop and stem lesions creating bare and brown patches. It has been discovered in ten states (CT, OH, OR, MA, MD, NC, NY, RI, PA, VA) and three Canadian provinces (BC, ON, QC).
To download the NC State report click here