Two widespread fungal infections target most maple species and do not spare the slotted maple. Find out here which symptoms you can use to recognize the diseases with tips for ecological control.
What diseases affect slot maple trees and how do you combat them?
Slotted maple diseases such as verticillium wilt and powdery mildew can cause leaf wilting, discoloration and stunted growth. Verticillium wilt requires cutting back affected shoots and changing location, while mildew can be controlled with a milk and water solution.
Verticillium wilt – tips for diagnosis and control
Fungal spores of the genus Verticillium reach the maple tree through the ground and clog the pathways. Visible symptoms of an infection include wilted leaves and dry branches in places. The disease spreads from the base to the tip, so that an Acer palmatum ultimately dies. If you cut through affected branches, dark brown ring-shaped discolorations can be seen. Effective fungicides are not yet available. How to Fight Verticillium Disease:
- Cut back all diseased shoots to he althy wood
- Burn the clippings or dispose of them in household waste
- Transplanting slot maple to a new location
Prepare a spacious planting pit at the new location, at the bottom of which you create a drainage made of sand or fine gravel. Mix one third of the excavated material with rhododendron soil. The more permeable and airy the soil, the better the chances that the sick sloth maple will regenerate on its own.
Identify and combat mildew - How to do it
Deeply slotted leaves in beautiful colors are the most beautiful decoration of the Acer palmatum. How devastating when the decorative leaves are covered with a mealy-gray fungal growth as a result of infection with powdery mildew. As the leaves progress, they turn brown and sadly fall to the ground. It doesn't have to come to that, because you can fight the disease with fresh milk. This is how it works:
- In the first step, cut off all affected leaves and shoots
- Add 125 ml of fresh milk to 1 liter of rainwater, supplemented with a drop of dishwashing liquid
Pour the solution into a hand sprayer. At intervals of 2 to 3 days, spray the remaining leaves on the upper and lower sides with the milk water until no more symptoms of the disease appear.
Tip
The symptoms of verticillium wilt and frost damage look very similar at first glance. There is a crucial difference: wilting fungi cause a maple tree to die slowly and in places. Frostbite causes leaves to dry out overnight on the entire plant, leaf drop and limp shoots.
