Austrian pine trees are a popular choice for residential and commercial landscapes due to their stately appearance and hardiness. However, they can fall victim to various fungal diseases that negatively impact their health. Dothistroma needle blight, diplodia tip blight, and armillaria root rot are some common fungal infections seen in Austrian pines. If left unchecked, these diseases can disfigure and even kill affected trees. Implementing proper preventive care and using the right treatment methods at the first signs of infection are key to getting rid of fungus on Austrian pine trees.
Understanding Common Fungal Diseases in Austrian Pines
It’s important to be able to accurately identify the type of fungus affecting your tree in order to treat it effectively. Here are some of the most prevalent fungal diseases found in Austrian pines:
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Dothistroma Needle Blight – This fungal infection is caused by the pathogen Dothistroma septosporum. It leads to premature needle drop and discoloration. Look for red-brown bands or spots on infected needles.
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Diplodia Tip Blight – Caused by the fungus Diplodia pinea this disease infects new shoots causing dieback. Resinous cankers form on infected branches.
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Armillaria Root Rot – Armillaria species such as A. mellea infect tree roots, resulting in crown thinning and eventually death. Look for white fungal growth under the bark near the soil line.
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Pine Needle Rust – Rust fungi like Coleosporium asterum infect needles resulting in yellow/orange pustules. Infections cause reduced growth and needle loss over time.
Implementing Preventive Measures
Stopping fungal diseases before they start is the ideal approach. Here are some key preventive measures for Austrian pines:
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Avoid overwatering and improve drainage if needed Excess moisture encourages fungal growth
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Space trees properly to allow air circulation and maximize sunlight exposure.
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Prune lower branches to prevent humidity buildup. Sterilize tools between cuts.
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Remove fallen debris and diseased needles to eliminate inoculum sources.
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Mulch around trees with organic matter to regulate soil temperature and moisture. Don’t pile mulch against the trunk.
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Fertilize appropriately to maintain vigor without excessive growth.
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Monitor for early symptoms and address issues promptly.
Using Cultural Control Methods
If a fungal disease is detected early, cultural control methods may be sufficient to resolve the problem. This involves modifying growing conditions to discourage fungal growth.
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Improve air circulation through corrective pruning and proper spacing.
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Rake up and dispose of infected fallen needles to reduce spore sources.
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Apply preventive fungicide drenches in spring/fall. Products with chlorothalonil or propiconazole can help.
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Water early in the day so foliage dries out fully. Adjust irrigation frequency/amount.
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Reduce humidity around trees by thinning dense interior branches.
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Fertilize in moderation in early spring to improve vigor without spurring excessive growth.
Implementing Chemical Treatments
For moderate or severe fungal infections, the application of fungicidal chemicals is generally required to save affected Austrian pines. Always read and follow label directions carefully.
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Systemic fungicides – These are absorbed and transported through the tree, providing extended control. Apply as soil drench or trunk injection. Examples include propiconazole, myclobutanil, and tebuconazole.
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Protectant fungicides – These coat plant tissues to block infection but don’t penetrate internally. Examples are chlorothalonil, mancozeb, and copper fungicides.
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Plant defense activators – These stimulate the tree’s natural defenses against fungal infection. Products containing phosphite salts or acibenzolar can be used.
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Combination products – Using both systemic and protectant fungicides together provides thorough disease control. Always check for compatibility.
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Repeat applications – Follow up with additional treatments on a 7-14 day schedule based on infection severity and product label.
Knowing When to Call a Professional
In cases of advanced fungal infections or if you are unsure about how to proceed, consulting a professional certified arborist is advisable. They can provide an accurate diagnosis, recommend appropriate fungicides and application methods, and properly treat diseased trees. For severe infections, intensive treatments like trunk injections performed by an arborist may be necessary to save the tree.
Providing Proper Aftercare
Once fungal issues have been resolved, continue monitoring treated Austrian pines closely and provide proper aftercare to aid recovery:
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Inspect regularly for return of symptoms or new infections. Retreat if needed.
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Remove treatment residues through light pruning. Disinfect tools after use.
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Rake up and dispose of fallen needles/debris to eliminate spore sources.
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Water thoroughly but avoid oversaturation. Let soil dry between waterings.
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Fertilize lightly in spring with a balanced, slow-release product to support recovery.
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Prune only when necessary, sterilizing tools before each cut. Avoid unnecessary stress.
Left unchecked, fungal diseases can severely damage the health and appearance of Austrian pine trees. By recognizing symptoms early, implementing preventive measures, and using appropriate cultural and chemical controls, you can effectively manage these harmful infections. Combining good sanitation practices, vigilant monitoring, and prompt treatment at the first sign of disease is key to successfully getting rid of fungus on Austrian pines. With proper care, your trees can thrive for years to come.
Managing Dothistroma and brown needle blight on pines
Jill ODonnell, , and Jan Byrne, MSU Diagnostic Services, Department of Plant, Soil and Microbial Sciences – June 14, 2013
Scotch, Austrian and white pine are susceptible to several needle blights that cause needles to brown, shed prematurely and may eventually kill the tree.
The two most common needle blights Michigan State University Extension educators and specialists find on pines in Christmas tree plantations are Dothistroma and brown spot needle blights. Symptoms of these diseases are very similar and knowing the tree species and when you are seeing the symptoms can help you identify which one you may have.
Dothistroma needle blight is caused by the fungus Mycosphaerella pini Rostr. This common pine pathogen kills needles of all ages and can weaken or kill Austrian pine trees. Recently, we have also found Dothistroma on white pine. The main symptom is dead needle tips beyond the yellow to tan needle spots. These spots enlarge to form distinct brown to reddish-brown bands.
The black fruiting bodies of the fungus can be seen in the dead spots or bands on the needles. The spores spread by wind and rain and can infect needles throughout the growing season. New needles are susceptible once they emerge from the needle sheaths. The black fruit bodies appear in the fall; however, the spores are released the following spring and summer.
The best protection of new needles can occur when applying copper-based materials as the new needles emerge from the needle sheaths and as the spores are released from the fruiting bodies. To protect foliage from infection, apply a registered fungicide containing copper or mancozeb in mid-June through mid-July. This year (2013), you might start earlier since trees are ahead of normal. Repeat the application two or three times as needed at seven- to 10-day intervals.
Brown spot needle blight
Brown spot needle blight (Mycosphaerella dearnessii, syn. Scirrhia acicola) is relatively new to Scotch pine in Michigan. Needle spots can appear on needles at any time of the year, but most commonly we find them during August and September when the tree suddenly turns brown just before harvest.
Even though we see the symptoms in the fall, fungicide applications should be timed when the new needles are about half grown (May-June) and a second spray about three weeks later. In rainy conditions, the spray interval may need to be shortened. Several fungicide products with chlorothalonil, mancozeb or copper are labeled for control.
Growers will also want to adjust their shearing practices to avoid moving spores into other plantations.
- Do not shear infected trees during wet weather because spores released at this time may be carried from tree to tree on workers’ clothes or shearing tools.
- Sterilize tools after shearing affected plantations by dipping in denatured alcohol for three minutes.
- Shear healthy plantations first so spores will not be carried into them from affected plantations.
Removing fungus on trees
FAQ
What is the fungus on Austrian pines?
What is killing my Austrian pine trees?
What is the disease in the Austrian pine?
Do Austrian pine trees get fungus?
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. Spraying with fungicide may slow the spread, but once infected, it is hard to save a tree.
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.
How do you get rid of pine fungus?
Treatment: The University of Minnesota Extension recommends applying copper fungicides once before buds open in the spring and again when needles have grown to their full length in the summer. Several years of treatment may be needed. Pruning infected branches and moving sprinklers away from pine needles also reduce the spread.
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.