Pine: Lophodermium needle cast

• Categories: Conifers Ornamentals Pine Pine Diseases
• Last review date: 2025-07-31 03:27

Biology

Lophodermium needle cast is a fungal disease infecting the needles of pines. There are 19 Lophodermium species in the Pacific Northwest.

One species of concern, L. seditiosum, infects current-season needles, which are killed by the next growing season. Yellow spots appear from late fall to spring. These later turn brownish, then whole needles turn reddish or yellow and drop by the following midsummer.

Infected needles typically display black, football-shaped fungal structures with a slit in the center. Some species of pine also develop characteristic black lines across infected needles.

Repeatedly infected trees may be stunted. Low branches are more severely affected.

• This disease may be confused with Lophodermella needle cast, which lacks the distinctive black, football-shaped structures.

Management Options

See "Using Integrated Pest Management (IPM) in the Landscape" for successful problem management techniques.

Non-chemical Management

Select non-chemical management options as your first choice!

• Reduce humid conditions which favor disease development (remove weeds under and near trees, thin canopy).
• Space plantings to provide good air circulation.
• Prune lower branches.
• Prune and destroy infected twigs and branches.

Chemical Management

• A minimum of 3 applications are required between late July and late September to control this disease.
• Homeowners should not make foliar applications to trees over 10 ft tall.
• Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.

Approved Pesticides

If you choose to use a pesticide, some examples of products that are legal in Washington are listed below. Some products are labeled for just INDOOR or just OUTDOOR use, or may allow both uses. Be sure to choose a product appropriate for your situation. Always read and follow all label directions.

• GardenTech Daconil Fungicide Concentrate
  Active ingredient: chlorothalonil
  EPA registration number: 67572-82-71004
• Ortho Max Garden Disease Control Concentrate
  Active ingredient: chlorothalonil
  EPA registration number: 239-2522
• This list may not include all products registered for this use.