Bulbs Flower Basics Flower Beds & Specialty Gardens Flower Garden Garden Furniture Garden Gnomes Garden Seeds Garden Sheds Garden Statues Garden Tools & Supplies Gardening Basics Green & Organic Groundcovers & Vines Growing Annuals Growing Basil Growing Beans Growing Berries Growing Blueberries Growing Cactus Growing Corn Growing Cotton Growing Edibles Growing Flowers Growing Garlic Growing Grapes Growing Grass Growing Herbs Growing Jasmine Growing Mint Growing Mushrooms Orchids Growing Peanuts Growing Perennials Growing Plants Growing Rosemary Growing Roses Growing Strawberries Growing Sunflowers Growing Thyme Growing Tomatoes Growing Tulips Growing Vegetables Herb Basics Herb Garden Indoor Growing Landscaping Basics Landscaping Patios Landscaping Plants Landscaping Shrubs Landscaping Trees Landscaping Walks & Pathways Lawn Basics Lawn Maintenance Lawn Mowers Lawn Ornaments Lawn Planting Lawn Tools Outdoor Growing Overall Landscape Planning Pests, Weeds & Problems Plant Basics Rock Garden Rose Garden Shrubs Soil Specialty Gardens Trees Vegetable Garden Yard Maintenance

Brown Spots on Maple Tree Leaves

How to Start Lemon Seeds Indoors - watch on youtube
Brown Spots on Maple Tree Leaves

Brown Spots on Maple Tree Leaves. Brown spots on maple tree leaves indicate two possible diseases: anthracnose and tar spots, both caused by fungal attack. Untreated, anthracnose can permanently damage a maple tree, while tar spots will merely be unsightly. Both diseases are treatable.

Brown spots on maple tree leaves indicate two possible diseases: anthracnose and tar spots, both caused by fungal attack. Untreated, anthracnose can permanently damage a maple tree, while tar spots will merely be unsightly. Both diseases are treatable.
Anthracnose
Anthracnose, a fungal disease, attacks following an unusually cool, wet spell occurring during bud break. While a single occurrence rarely harms the tree, annual infections will reduce growth and could predispose the tree to other stress.
Anthracnose: Symptoms and Damage
In addition to light to dark brown spots along or in between the leaf veins, purple-brown areas may form along the veins which may extend to the leaf margin.
The damage that may occur includes: buds death that causes short twigs to develop; death or girdling of leaves, small twigs and smaller branches (up to one inch in diameter); early leaf loss which, over a repeated basis, weakens the tree and predisposes it to borer attack and winter injury; and early leaf drop.
Anthracnose: Treatment
Treatment may not require chemicals. Rake up any fallen leaves, bag them, and remove them from the yard. Shred, compost or burn the leaves.
Prune the dead twigs or small branches, burn or bury them, then prune the tree to thin the crown to improve air movement and promote faster leaf drying. In the fall, fertilize approximately one month after the first frost. In the spring, fertilize approximately one month before the date of the last frost.
If these methods do not rid the tree of the infestation, spray the tree with a fungicide containing mancozeb. Follow this with two applications 10 to 14 days apart during leaf expansion.
Tar Spots
Tar spots, a fungal disease, attacks usually beginning in mid-June. Tar spot by itself rarely damages the tree's health, but it makes the tree unsightly with the raised, brown and black spots it causes on the upper leaf surfaces.
Tar Spots: Symptoms and Damage
A tree infected with tar spots will first show pale yellow spots in mid-June, which intensifies in color as summer progresses. The spot usually reaches dark brown and/or black by mid-July to early August. The spots' surface may show patterns of wavy indentations or ripples.
Size of the spots will vary between the size of a pin-head up to 1 1/2 inches in diameter, depending on the variety of maple. Long term infections may affect the seed growth or cause early leaf drop.
Tar Spots: Treatment
Again, treatment may not require chemicals. Rake up and destroy all fallen leaves to reduce the amount of overwintering spots that produce spores in the spring. Compost or burn the leaves. For continued infection, spray with a fungicide, completely covering the leaf tissue. Repeat annually.

Check out these related posts