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How to Treat Common Diseases of Maple Trees

Autumn Maple Tree under Blue Sky image by loongirl from

The maple tree is a deciduous tree native to North America. The maple tree, or Aceraceae, family comprises more than 120 varied-sized species, some of which can reach mature heights of 90 feet. Though the hardiness, growth rates and irrigation needs vary among each vaiety, the maple trees’ disease susceptibility is quite similar. Anthracnose, powdery mildew, root rot and verticillium wilt are just some of the maple family’s most common diseases. With every variation, successfully treating the diseased maple involves a combination of vigorous growth, general maintenance and pruning.

Inspect the infected maple tree thoroughly. Identify any signs of infection. Look for symptoms such as wilting, weakened branches, loss of vigor, yellowing or browning of foliage, foliage spots or deadening, early defoliation, cankers, growth stunt and dieback.

Prune the infected areas from the tree. Use sharp, sterile pruning shears to remove the infected foliage, twigs and branches. Cut infected branches using an angular cut and cut back at least an inch away from the infection. Cut infected twigs using a flush cut at the branch intersection. Sterilize the shears between each cut to avoid spreading the infection throughout the tree.

Remove the defoliated debris and pruned trimmings from around the tree. Always keep the maple tree’s area free of debris as many maple tree diseases develop and germinate in these areas. Discard the debris and never use as mulch or compost.

Treat the maple tree with a fungicidal or bacterial that correlates with the infection. Speak with a horticultural or nursery specialist for assistance in identifying the exact disease and required chemical treatment. Take a list of the identified symptoms to discuss during the assessment. Apply the chemical treatments on dry, cool days when no rain is expected and when temperatures are below 85 degrees F.

Promote and maintain a vigorously growing maple tree. Irrigate the tree thoroughly and infrequently, approximately once every seven to 10 days. Provide the maple tree with 1.5 to 2 inches of water using a slow irrigation system. Irrigate the tree in the early morning to avoid the evaporation effects of the afternoon sun.

Feed the maple tree in the early spring and again in the early summer. Use a well-balanced, slow-release fertilizer such as a 20-20-20 or 40-40-40 combination. Distribute the fertilizer evenly around the tree. Ensure that the fertilizer is at least one foot from the base of the tree to prevent root burn. Water the fertilizer thoroughly into the soil with 1.5 to 2 inches of water.

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