Advise seen here taken from the Virginia Cooperative Extension's website. We will update with new info biweekly or monthly.
Boxwood blight (also called “box blight” in Europe), caused by the fungal pathogen Cylindrocladium pseudonaviculatum (C. buxicola), was found for the first time in the United States in North Carolina, Virginia and Connecticut in 2011. Boxwood blight was first reported in the United Kingdom in the early to mid 1990’s and had spread through Europe and New Zealand by 1998. The origin of the pathogen is unknown. The first reported infestation in the U.S. was in a North Carolina nursery and the disease was introduced to Virginia on plants from that nursery. It is not known how C. pseudonaviculatum was initially introduced to North Carolina. Spread outside the two Virginia locations, both of which are fields owned by a single nursery, has not been reported. The Virginia Department of Agriculture and Consumer Services (VDACS) and the North Carolina Department of Agriculture and Consumer Services are implementing strategies to eradicate the pathogen from infested fields. However, growers should be aware of the symptoms of boxwood blight and monitor nursery and landscape boxwoods for symptoms.
Symptoms, Signs and Impacts:
The fungal pathogen infects leaves and branches of boxwoods, causing light or dark brown leaf spots with a dark border, defoliation and dieback. Infected branches develop long blackish-brown streaks on stems. In warm, humid conditions the fungus produces clusters of white spores visible to the naked eye on the underside of leaves and on stems. The fungus does not infect roots; thus, plants may re-grow even after a severe infection. However, repeated defoliation and dieback can predispose plants to other diseases, such as Volutella blight, resulting in decline and eventual death.
Although boxwoods are not typically killed directly by C. pseudonaviculatum, rapid defoliation renders boxwoods unmarketable and gardens unsightly. The pathogen thrives in humid environments, which are typically present in production nurseries and propagation houses. Once boxwood blight is established in production nurseries, regular use of fungicides is required to control the disease; however, Cylindrocladium diseases are difficult to control with fungicides. The pathogen has caused significant damage to boxwoods in European landscapes, which suggests this disease can potentially damage historic boxwood gardens in Virginia.