University of Maryland Extension

Macrophoma Leaf Spot

Macrophoma infected leaf
Black, raised fruiting body of Macrophoma on boxwood leaf

  • Most boxwood are susceptible to infection by the weakly parasitic fungus, Macrophoma candollei. The most obvious symptoms are the many tiny black raised fruiting bodies found on dying or dead straw-colored leaves.


  • In home landscapes proper pruning and thinning, instead of shearing the shrubs, is the most effective way to manage this disease. Thinning the shrub helps to increase air circulation helping the leaves to dry out and not stay constantly moist. 
  • Fungicide treatment is not necessary or recommended. 

Additional Resource


Maintained by the IET Department of the College of Agriculture and Natural Resources. © 2021. Web Accessibility

University programs, activities, and facilities are available to all without regard to race, color, sex, gender identity or expression, sexual orientation, marital status, age, national origin, political affiliation, physical or mental disability, religion, protected veteran status, genetic information, personal appearance, or any other legally protected class. If you need a reasonable accommodation to participate in any event or activity, please contact your local University of Maryland Extension Office.