If Japanese Japanese maple suddenly shows withered leaves and withered shoots, the dangerous Verticillium wilt is often behind it - especially when the water supply is actually optimal. The exotic trees can only be saved with luck, because there is still no effective remedy against the wilt disease.

Dry leaves are often a sign of disease

Verticillium wilt is often behind dry leaves

Withered branches and dead leaves, which develop particularly in midsummer when the weather is warm and dry, are often a sign of infection with the soil-dwelling Verticillium fungus. This penetrates the wood of the plant via the pathways and prevents an adequate supply of water and nutrients. As a result, the tree slowly begins to die off, and the fungus continues to spread. Wilt disease usually migrates from bottom to top and from the base to the tips of the shoots.

clinical picture and symptoms

A first sign of the wilt disease are often necrotic - i.e. dead - leaf edges, which can sometimes be confused with sunburn, especially in the initial phase. However, this basically affects all leaves lying in the sun and not just individual shoots. Furthermore, the leaves dry up, branches wither and die. The wilt disease can be identified without a doubt if you remove such a branch and cut it through once. The actually light wood is interspersed with dark spots and dots. This is the actual mushroom network.

Weakened trees particularly vulnerable

Japanese maples that have been weakened by improper location and/or improper care are particularly susceptible to infection with Verticillium wilt. In particular, a location that is too damp or waterlogging, but also very dense and oxygen-poor soils prove to be fatal.

Control Verticillium wilt

Unfortunately, there is still no effective fungicide that can be used to combat wilt disease - since the fungus is firmly attached to the wood, it is well protected from such agents. Instead, you have to generously cut away affected parts and immediately dispose of them with household waste or burn them. However, infected material must never be put on the compost, otherwise the disease can spread further. It is also advisable to replant infested maples. After all, the pathogen is in the soil, so that a new infection is always possible.

tips

However, dry leaves can also have other causes, such as too much water/drought or sunburn.

Category:

Trees