Basically, the thuja, also known as the tree of life, is a very robust hedge plant. Nevertheless, thujas often turn brown. This is due to illnesses that can occur due to care errors or external circumstances. What symptoms appear and how do you combat thuja diseases?
What diseases can occur in a thuja?
In the case of a thuja, care errors, fungal diseases, pest infestations or external influences can lead to illness. Discoloration of the needles can indicate incorrect care, magnesium deficiency or fungal or pest infestation. Countermeasures include soil improvement, proper irrigation and pest control.
What challenges can arise when caring for thuja?
Various difficulties may arise, including:
- Care errors
- Fungal infections
- Pest Infestation
- external environmental influences
Illnesses are rare, but when they do occur, they are usually due to poor care. Mistakes often occur, particularly in the area of water supply. Often the thuja hedge is either not watered sufficiently or waterlogging forms at its location, which can damage the roots.
It should also be noted that discoloration of the needles cannot only be caused by illness. Over-fertilization with mineral fertilizers or exposure to road s alt in winter can also lead to such changes.
If the thuja needles turn yellow, this could be a sign of a magnesium deficiency. This can be effectively remedied by targeted fertilization with Epsom s alt.
Recognizing symptoms
Whenever the tree of life changes color, the gardener should investigate the causes. If the thuja turns brown inside in autumn, it is a natural process. She then throws off old needles.
If only the shoot tips turn brown or yellow, white spots appear on the trunk or the entire tree appears to be drying out, either incorrect care or illness are responsible.
Pest infestation caused by the leaf miner
Brown shoot tips can be caused by a leaf miner infestation. In addition to the brown tips, the symptoms include feeding passages in the shoots. On the needles there are small black dots, the excrement of the pests.
Fungal infections in Thuja
Fungal diseases often manifest themselves through needle discoloration and a noticeably soft consistency of the affected areas. Typically, the infestation begins at the tips of the shoots and then quickly spreads to the trunk.
If the trunk appears whitish and mottled at its base, the cause may be root rot. This disease is spread by fungal spores and is promoted by excessively moist or compacted locations. It is important to pay attention to such signs and react quickly, as fungal diseases can severely impact plant vitality and cause significant, long-term damage.
| Fungal disease | Symptoms | Measures |
|---|---|---|
| Hallimasch root rot | Large yellow mushroom networks, mushrooms sprouting from the bark | Remove affected specimens immediately |
| Pestalotia shoot death | Brown coloring of the leaf scales, dark brown spots on shoots | Increase the pH value of the soil, remove infected parts |
| Kabatina drive death | Young leaves discolored brown, black spore beds | Remove affected plant parts, prepare the soil |
| Flake tan | Focus on older leaf scales, similar spots and spore beds as Kabatina | Similar measures as for the Kabatina shoot death |
Fighting thuja diseases
If the thuja diseases are caused by incorrect care, the tree of life can often still be saved. Either provide better drainage or water more regularly. Use mineral fertilizers sparingly and prefer to use organic fertilizers such as compost or manure.
If the thuja is infected with pests, cut off all affected parts. If you have to cut into the old wood, the thuja will not sprout there again.
In the case of a fungal infection, it depends on how badly the tree of life is affected. If there is severe damage and advanced root rot, the only option is to clear the tree of life completely and replace the soil. The trees in the hedge that are still he althy need to be treated with fungicides. This is the only way to prevent further spread.
Tip
If the thuja turns black, it is not a disease, but a manganese deficiency. It is caused by soils that are too acidic. You can combat this deficiency by liming the soil.
