Cylindrocladium pseudonaviculatum infects all aboveground portions of boxwood, but does not appear to infect the roots. Initial symptoms appear as dark or light brown spots or lesions on the leaves. These lesions often have dark borders.
Spots enlarge and then coalesce, often with a concentric pattern or a zonate appearance. Infected leaves then turn brown or straw colored, so infected plants look “blighted”. Defoliation often
occurs very quickly after foliar symptoms
first develop.