The graceful, evergreen Austrian pine tree (Pinus nigra) is a popular ornamental landscape tree, especially in colder climates. Its attractively shaped, lush green needles provide great cover and beauty. However, Austrian pines can fall victim to several diseases that affect their needles and branches. If you notice your pine’s needles turning yellow, brown, spotty, or falling off, it likely has a disease. Read on to learn how to identify and treat the most common Austrian pine tree diseases.
Common Diseases
Here are some of the most prevalent diseases of Austrian pine trees
Diplodia Tip Blight
This fungal disease infects new shoots, causing needles to turn brown and dieback Look for cankers oozing resin on dead tips. Prune out infected branches Improve air circulation around trees. Avoid overhead watering. Apply fungicide sprays in spring as new growth appears.
Dothistroma Needle Blight
This fungus turns needles reddish-brown with dark bands. It spreads in wet weather. Prominent yellowing precedes needle drop. Improve air flow around trees. Rake and dispose of fallen needles. Apply copper fungicide spray in early summer.
Sphaeropsis Tip Blight
Infected shoots turn yellowish then reddish-brown. Resin drips from cankers on dead tips. Prune out dead branches. Allow more space between trees. Apply fungicide spray in spring as buds swell.
Pine Wilt
This deadly nematode clogs water-conducting tissue. Needles rapidly wilt from grayish-green to brown. No control exists. Uproot and destroy infected trees ASAP to prevent spread.
Pine Sawyer Beetles
Adult beetles bore into trunks, allowing fungal rot entry. Sawdust around tree base and small holes indicate infestation. Spray insecticide on bark. Install pheromone traps. Keep trees healthy with proper care.
Pine Needle Scale
Tiny insects feast on sap, causing yellow mottling. Look for white specks on needles. Prune out heavily infested branches. Spray horticultural oil or insecticidal soap in spring. Release ladybugs.
Prevention Tips
Here are some ways to help prevent diseases and pests from damaging your Austrian pines:
- Select disease-resistant cultivars when available
- Provide sufficient water during dry periods
- Improve air circulation with proper spacing and pruning
- Clean up fallen needles and debris
- Disinfect pruning tools between trees
- Avoid overhead watering
- Monitor for early signs of infection
- Treat diseases and pests promptly
- Fertilize trees appropriately to maintain vigor
- Remove heavily infected trees to prevent spread
When to Call an Arborist
If you suspect your Austrian pine has a disease but you’re unsure of the cause, call a certified arborist. Arborists have the knowledge and tools to accurately diagnose most tree diseases. They can then advise you on the proper treatment methods for your type of infection. An arborist may take a sample of diseased tissue for lab testing to confirm the pathogen. Don’t delay in seeking professional help, or the disease may kill the tree.
How to manage Dothistroma needle blight Needle spots on one year old needles and needle tip death on two year old needles
- Do not overcrowd plants. Use the mature size of the tree as a spacing guide when planting.
- Remove the bottom most branches from the trunk to help increase circulation around the tree canopy.
- Remove all weeds under the trees.
- Maintain a 3 to 4 inch deep, even layer of wood chip mulch around your tree to prevent weed growth.
- Leave at least a 2 inch space between the mulch and the trunk to allow for air movement.
- Do not mound the mulch around the trunk of the tree.
- Inspect the depth of the mulch layer each year. Add additional mulch only to maintain a 3 to 4 inch depth.
How does Dothistroma needle blight survive and spread? Needle spots, bands and dead needle tips from Dothistroma needle blight
- Dothistroma needle blight is caused by the fungus Dothistroma septosporum (syn. Mycosphaerella pini).
- Dothistroma needle blight is a slow-moving disease that takes over a full year to complete its life cycle. It takes several years of repeated infection to develop into a serious problem within the tree canopy.
- Spores are produced on infected needles throughout the growing season whenever cool, wet weather occurs.
- Spores are spread by wind or rain to needles within the same tree or in neighboring trees.
- Infection occurs if spores land on susceptible needles under favorable weather conditions.
- Second year or older needles are susceptible to infection anytime during the growing season.
- Young needles are resistant until they reach maturity in early to mid summer.
- Several consecutive days of cool (41-77°F), wet weather are needed for successful infection.
- Reddish brown spots or bands appear on needles in the fall.
- Needle spots eventually girdle the pine needle. The needle beyond the band then dies and turns brown leaving the bottom portion of the needle green.
- Tiny black fungal fruiting bodies called stromata appear in the bands or in dead areas of the needles. These fruiting bodies will release spores the following year.
- Infected needles may remain attached to the tree for one or two years depending on the age of the needle at the time of the infection.
- Eventually infected needles turn completely brown and fall off prematurely.
Pine Tree Diseases: All About Diagnosing and Treating Pine Tree Problems
Do Austrian pine trees have blight?
Austrian pine trees are relatively resistant to pests and diseases but may occasionally encounter issues such as bark beetles, pine needle scale, or diplodia tip blight. Inspect your tree regularly for signs of pest infestation or disease symptoms, such as yellowing needles, oozing sap, or stunted growth.
Is pine good for you?
Pine bark could potentially be beneficial due to its potential anti-oxidant and anti-inflammatory properties. Due to its antioxidant properties, pine bark could help to protect the body from excess free radical build up, that could lead to oxidative stress. Oxidative stress can in return result in cell damage, poor healing and increased risk for various diseases.
What are Austrian pine trees?
Austrian pine trees (Pinus nigra) are popular landscape trees known for their dark green needles and sturdy, pyramid-shaped structure. These hardy evergreens are native to Europe and are commonly planted in parks, gardens, and urban areas for their ornamental value and ability to thrive in various soil conditions.
Do Austrian pine trees die if left unprotected?
Left above ground and unprotected, a potted tree’s roots may die. The Austrian pine is prey to many fungal diseases, such as lophodermium needle cast, diplodia (sphaeropsis) tip blight, as well as various wood rots and decays. Remove affected branches as you spot them.