A project supported by the

Horticultural Research Institute and AmericanHort Foundation
Boxwood Blight Insight Group

Diagnose · Manage · Learn

Boxwood Blight Knowledge Center

Diagnostic aids, management strategies, seminars and research on boxwood blight.

Diagnostic Aids Sanitation International Seminars BBIG Seminars On-Demand at Cultivate Outreach Epidemiology More Resources

Section 1

Diagnostic Aids & Management Strategies

Blight Symptoms

Boxwood

Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)Boxwood blight (OSU Santamaria, 2016)

Photo credit: OSU Santamaria 2016

Pachysandra

P. procumbens Leaf spot (LaMondia CAES)P procumbens stem infection (LaMondia CAES)Pachysandra stem lesions (LaMondia CAES)Pachysandra symptoms (LaMondia CAES)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)Pachysandra leaf spot (OSU Santamaria, 2016)

Photo credit: LaMondia CAES; OSU Santamaria 2016

Sweet Box

Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (Va, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (Va, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)Sarcococca blight (VA, 2015)

Photo credit: VA 2015

Forecasting

Boxwood Blight Forecasting App & Push Notification

Scouting

Scouting, Diagnostic Guides & Tools

Scouting for Boxwood Blight (video)

  • Castroagudín, V., Yang, X., Daughtrey, M., Luster, D., Pscheidt, J., Weiland, J., and Crouch, J. 2020. Boxwood blight disease: A diagnostic guide. Plant Health Progress 21:291-300. https://doi.org/10.1094/PHP-06-20-0053-DG
  • Singh, R., and Doyle, V. P. 2017. Boxwood dieback caused by Colletotrichum theobromicola: a diagnostic guide. Plant Health Progress 18:174-180. https://doi.org/10.1094/PHP-04-17-0024-DG
  • Weiland, J. and Pscheidt, J. 2020. Scouting for boxwood blight. Digger (March 2020 Issue):25-28. Click here to view the PDF
  • Yang, X., Castroagudin, V., Daughtrey, M., Loyd, A., Weiland, J., Shishkoff, N., Baysal-Gurel, F., Santamaria, L., Salgado-Salazer, C., LaMondia, J., Crouch, J., and Luster, D. 2021. A diagnostic guide for Volutella blight affecting Buxaceae. Plant Health Progress. https://doi.org/10.1094/PHP-02-21-0052-DG

Integrated Disease Management

Boxwood Blight Resistance

NewGen Boxwood Better Boxwood Star Roses and Plants Boxwoods

  • Hong, C. X. 2023. Building health into boxwood crops and plantings by making informed cultivar selection. Plant Health Progress open access
  • Brand, T., Beltz, H., Ehsen, B., Adhikari, U., Daughtrey, M. L., Luster, D. G., Kong, P., and Hong, C. X. 2023. Multi-year field plantings evaluating boxwood cultivars for susceptibility to the blight pathogens (Calonectria spp.) in Northern Germany. Plant Disease 107:713-719 open access
  • Kramer, M., Guo, Y. H., and Pooler, M. 2020. Ranking resistance of Buxus cultivars to boxwood blight. Journal of Environmental Horticulture 38(2):50-55 open access
  • Yoder, K. S., Dunn, R. A., Saunders, J. B., Mays, T. R., Yanny, M. D., Hong, C. X., and Scoggins, H. L. 2022. Field performance of Buxus cultivars and selections against boxwood leafminer and boxwood blight. Journal of Environmental Horticulture 40(4):129-142 open access
  • Omolehin, O., Keller, J., Gouker, F., Daughtrey, M. L., Luster, D. G., Pscheidt, J., and Hong, C. X. 2022. Combating an invasive boxwood pathogen – Calonectria pseudonaviculata in the United States by shifting production to more resistant cultivars. Plant Disease. https://doi.org/10.1094/PDIS-09-22-2124-RE
  • Richardson, P. A., Daughtrey, M., and Hong, C. X. 2020. Indications of susceptibility to Calonectria pseudonavicualata in some common groundcovers and boxwood companion plants. Plant Disease 104:1127-1132 open access

Boxwood Blight Maps

Global distribution map of boxwood blight

Hong, C. X. 2024. Global distribution of boxwood blight caused by Calonectria pseudonaviculata sensu lato, color coded by the time of its first positive detection.

United States map

Hong, C. X. 2023. United States map of boxwood blight by the time of its first confirmed invasion.

Click here to view the map
Map of Calonectria henricotiae in Europe

Hong, C. X. 2024. Updated map of the boxwood blight pathogen – Calonectria henricotiae in Europe, color coded by the time of its first observation.

Boxwood Cleanliness Programs

Section 2

Sanitizers & Sanitation Practices

Cultural Control

Ohkura, M., Nackley, L., Scagel, C., and Weiland, J. 2021. Call it “herbal distancing.” Digger (published by the Oregon Association of Nurseries) August issue.

Open access

Fungicide Options & Chemical Protection

Fungicides for boxwood blight control.

View table (PDF)

Boxwood Blight Biology

Spread of Blight Disease Illustration by Nina Shishkoff.

Click Here (PPTX)

Best Management Practices

  • Bush, E. Hansen, M. A., Dart, N., Hong, C. X., Bordas, A., and Likins, T. M. 2016. Best management practices for boxwood blight in the Virginia home landscape. Virginia Boxwood Blight Task Force open access
  • Bily, D., and Hong, C. X. 2023. Best management practices for boxwood blight in Virginia nurseries. Virginia Boxwood Blight Task Force open access

Section 3

International Boxwood Seminars

Section 4

BBIG Boxwood Seminars

BBIG Boxwood Seminars

Prospecting for Biocontrols

Dr. Kong · March 14, 2025

It is neither economically sustainable nor environmentally acceptable to make multiple fungicide applications to protect boxwood, a key nursery crop and iconic landscape plant, from boxwood…

View seminar
BBIG Boxwood Seminars

Battling Boxwood Blight

Dr. James LaMondia · August 23, 2023

The Boxwood Blight Insight Group is pleased to host the next webinar in their on-going efforts to assist the industry manage boxwood health in the nursery…

View seminar

Section 5

BBIG On-Demand at Cultivate

2022

2021

Section 6

Outreach to Different Stakeholders

Horticulturists

Plant Disease · 2025

Flutriafol drench provides season-long protection of boxwood plantings pre-infected by Calonectria pseudonaviculata in the Mid-Atlantic

Likins, M., Davis, B., Anderson, P., Gillis, B., and Hong, C. X. 2025.

View Open Access Article

Plant Disease · 2025

Detached leaf assays reveals long-term efficacy of the systemic fungicide flutriafol against boxwood blight

Sacher, G. and Pscheidt, J. 2025.

View Open Access Article

EPA IPM Webinar · March 5, 2024

Managing boxwood blight and box tree moth

By Dr. Chuan Hong of Virginia Tech and Dr. Greg Simmons of USDA Animal and Plant Inspection Service.

Click here to view recording

Third BBIG Annual Meeting · May 9, 2024

Reducing boxwood stresses in the landscape

By Dr. Lynn Batdorf, International Registration Authority – Buxus.

Dixon Gallery and Gardens · February 18, 2022

Boxwood Seminar – Growing the Shrub We All Know and Love Despite Boxwood Blight

By Lynn Batdorf, Chris Cooper, Fulya-Basal-Gurel, Leslie Hollandsworth, Katy Kilbourne, Booker T. Leigh, Bennett Saunders at a day-long workshop in Memphis, TN.

Click here to view recording

Floraculture International · March 2024

Help Is On The Way

Gress, A. 2024. Help is on the way – don't give up on box just yet. Floraculture International (March 2024 issue):18-19.

Click here to download the PDF

Landscaping Professionals

BBIG Project Advisory Panel · December 1, 2023

Boxwood in the Landscape: Success and Shortcomings

By Mr. Michael Gaines. This talk was presented at a quarterly BBIG Project Advisory Panel meeting, sharing his experience and tips on how to successfully manage boxwood blight in the landscapes.

First Responders

January 17, 2024

The National Plant Diagnostic Network Symposium – Boxwood Blight Insight Group

First Session

  • Introduction: boxwood blight effects and how we are coping by Margery Daughtrey
  • Boxwood blight pathogen morphology and how it differs from other pathogens by Xiao Yang
  • Diagnostic assays for the boxwood blight pathogens Calonectria pseudonaviculata and C. henricotiae by Doug Luster
  • Sampling and detection methods for boxwood blight in nurseries by Mana Ohkura
Second Session
  • Boxwood, the plant and its blight symptom expression by Nina Shishkoff
  • New IPM tools for boxwood blight by Chuan Hong

March 16, 2022

The Great Plain Diagnostic Network Webinar: BBIG, a team tackling boxwood blight – sharing progress on diagnostics, extension and outreach

By Ms. Karen Snover-Clift, Ms. Margery Daughtrey, and Dr. Douglas Luster.

April 11 to 13, 2022

Panel Discussion about Boxwood at the Central Plant Board Meeting

By Ms. Margery Daughtrey, Dr. Russ Bullock, and Abigail Weisner.

Science Communities

American Phytopathological Society · August 2, 2021

Idea Café – Boxwood Blight Insight Group (BBIG) Fighting a Good Fight against Boxwood Blight

At the Annual Meeting of the American Phytopathological Society.

APS Southern Division · March 7 to 10, 2022

Symposium – Ornamental Production Challenges and Perspectives: A Case Study of Boxwood Blight

At the 99th Annual Meeting of the American Phytopathological Society – Southern Division in Chattanooga, TN.

APS Annual Meeting · August 6 to 10, 2022

Symposium – Epidemiology, Diagnosis, and Management of an Emerging Disease – Boxwood Blight

At the Annual Meeting of the American Phytopathological Society in Pittsburgh, PA.

Section 7

International Boxwood Blight Epidemiology (IBBE) Working Group Meetings

August 10, 2021

1st IBBE Meeting

  • Boxwood blight epidemiology: research goals, approaches, key processes and considerations, collaboration and communication plans — By Chuan Hong of Virginia Tech
  • Boxwood epidemiology research updates — By Drs. Srikanth Kodati and Jim LaMondia of Connecticut Agricultural Experiment Station
  • Boxwood blight infection risk forecasting models — By Drs. Len Coop and Brittany Barker of Oregon State University

View Recording

October 25, 2021

2nd IBBE Meeting

  • Predicting boxwood blight infection and establishment risk using CLIMEX, correlative, and DDRP modeling platforms — By Drs. Len Coop and Brittany Barker of Oregon State University
  • Long-term monitoring of Boxwood blight symptom development in an open-air nursery in coastal California – update — By Drs. Wolfgang Schweigkofler and Nilwala Abeysekara of Dominican University of California

View Recording

February 7, 2022

3rd IBBE Meeting

  • What weather conditions make an area hotspot for boxwood blight — By Dr. Urmila Adhikari of Virginia Tech

View Recording

May 9, 2022

4th IBBE Meeting

  • Attempting to understand boxwood blight epidemiology in landscape plantings through diagnostic sample confirmations — By Dr. Andrew Loyd of Bartlett Tree Experts

View Recording

October 17, 2022

5th IBBE Meeting

  • Models for boxwood blight infection and establishment risk — By Drs. Len Coop and Brittany Barker of Oregon State University

View Recording

Section 8

More Resources

Boxwood

Volutella Blight & Other Boxwood Diseases

  • Boxwood Browning, Blights, and Cankers – 2023 Updates by Todd Abrahamson of Purdue University on July 25, 2023 in Landscape Report Issue: 23-11
  • Re-Visiting Volutella and Browned Boxwood by Joe Boggs of Ohio State University on July 17, 2023 in Buckeye Yard & Garden onLine