Keeping your property healthy is important, and watching for signs of tree diseases is essential. Trees offer a majestic presence in our landscape, and healthy trees represent 5%-20% of a home’s value. Here is a basic primer on tree diseases.
Four ways tree diseases attack the landscape
Like the human body, a tree can be attacked by different diseases.
- Diseases can attack a tree’s foliage, its leaves or needles, harming respiration and photosynthesis.
- Diseases can attack a tree’s bark and wood.
- Diseases can attack the tree’s root system, affecting water and nutrient uptake.
- Finally, disease can affect a tree’s vascular system, much like arterial disease in humans affects blood circulation.
Examples of tree diseases in each system
- Among diseases that affect a tree’s foliage, powdery mildew and anthracnose can be managed both by pruning to improve air circulation and by applying fungicides. Pines and other needle species can develop blights and casts caused by fungal pathogens, which require fungicide treatment followed by reduced watering.
- Diseases of the bark and wood often take the form of cankers, such as aspen canker, Thyronectria canker, and chestnut blight. Treat with proper fertilization and by pruning away diseased branches.
- Examples of systemic and vascular diseases include oak wilt and Dutch elm disease, which can be managed by avoiding pruning during certain times of year, spraying for bark beetles, and removing diseased trees to help isolate the disease from others.
- Finally, root diseases are characterized by poor growth and wilted leaves despite good watering. Examples are Armillaria root rot and Heterobasidion annosum root rot. Treat by aerating the soil and, in some cases, with fungicides.
Related – Planting Roots: How to Pick the Best Trees for Your Home
