Dothistroma Needle Blight
MODERATEDothistroma septosporum
Overview
A fungal disease of pines that causes premature needle loss and can significantly reduce growth and vigor. It affects many pine species but is especially damaging to Austrian, ponderosa, and Monterey pines. It has increased in severity with climate change.
- Type
- Fungus
- Severity
- MODERATE
- Source
- USFS
Symptoms
Reddish-brown needle bands and spots, needle tips dying beyond the infection point while base stays green, premature needle drop starting on lower branches, thin canopy with only current-year needles retained
Affected Species
Geographic Spread
Treatments
Copper Fungicide Spray
Application of copper-based fungicide in mid to late spring as new needles elongate and during rainy periods. May need repeated application in wet years.
Species Diversification
Replace highly susceptible pine species (Austrian pine) with less susceptible species or resistant varieties in landscape and windbreak plantings.
Recommended Products & Tools
Helpful supplies for managing Dothistroma Needle Blight. Always read and follow label directions, and confirm a diagnosis before treating.
Broad-spectrum protectant for many fungal leaf and bark diseases.
Preventive spray for needle cast, leaf spots, and blights.
Sharp, clean cuts to remove affected wood — a tree-care essential.
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Frequently Asked Questions
What is Dothistroma Needle Blight?
A fungal disease of pines that causes premature needle loss and can significantly reduce growth and vigor. It affects many pine species but is especially damaging to Austrian, ponderosa, and Monterey pines. It has increased in severity with climate change.
What are the symptoms of Dothistroma Needle Blight?
Reddish-brown needle bands and spots, needle tips dying beyond the infection point while base stays green, premature needle drop starting on lower branches, thin canopy with only current-year needles retained
Where is Dothistroma Needle Blight currently found?
Dothistroma Needle Blight is currently active in California, Colorado, Connecticut, Iowa, Idaho, Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, Montana, Nebraska, New York, Ohio, Oregon, Pennsylvania, Washington, Wisconsin. It has been reported in 19 total states across the United States.
What plants are affected by Dothistroma Needle Blight?
Dothistroma Needle Blight affects Ponderosa Pine, Eastern White Pine. Susceptibility varies by species.
How do I treat Dothistroma Needle Blight?
Treatment options for Dothistroma Needle Blight include: Copper Fungicide Spray, Species Diversification. Treatment approaches may include chemical, biological, cultural, and mechanical methods depending on the severity and context.