Major tree diseases

Trees are living things and are infected and affected by infections every day of their lives. If they are not protected from the condition, they will eventually die and most likely leave a bad trail behind of infected trees.

The primary causes of diseases in trees are pests and insects. These transfer infections and causing germs from one tree to another. The principal challenge in controlling tree diseases are the ease at which new infections occur, some fungus are easily carried around by the wind and cause diseases to the trees they get.

Powdery mildew

It is a fungal disease manifested by the presence of whitish powder on the leaves of a tree. The infected leaves eventually die off. To treat and control the disease use recommended fungicides or wettable powder sulfur. You can also make your spray by mixing one gallon of water with one full spoon of baking soda and a half spoon of liquid soap. you can find this at

Do not spray the affected trees when the sun is hot nor use stored mixtures. Pour any left chemical mixture.

Tree canker disease

Cankers on trees are dead patches on the bark, stem, branches or twigs of a tree. They are caused by a fungus that enters the bark through a wounded place and burrows between the wood and the bark. The fungi consume the tree from inside and cause death patches which further opens more entry points for disease-causing pathogens.

Cankers vary on tree depending on the region. The main types are

  • Thyronectria canker which is caused by fungi and is mostly common on honey locust trees.
  • Nectria canker which mostly affects deciduous trees.
  • Cytospora canker which is common on fruit trees and shrub and other types of conifers.
  • Hypoxylon canker which mostly affects the oak trees.

To prevent the spread of canker disease use sterilized cutting tools to remove infected parts of the tree. Also, ensure pruning is only done during dry seasons.

Root and butt rot diseases

It is a fungal disease that mostly affects the area around the base of the tree where the tree comes into contact with the soil. If it affects the roots, the resulting condition is root rot. After infecting the roots and the butt, it then travels the tree upward up to one and a half meters high. Some of the fungi which cause these rotting conditions are Serpula himantioides and Ganoderma zonatum fungi.

The presence of water or excess moisture in the soil for a prolonged period catalyzes the disease.

Diplodia tip blight

It is a fungal condition that affects the conifer trees and more specifically the pine trees. It mostly affects trees which are more than 15 years with effects being more sphere in trees older than 30 years. It kills the most current branch ends, and when you look at an infected tree, you will see brown patches all over the crown of the tree.

To control the disease remove and destroy all the affected seeds since they contain the spores which are transmitted and cause more infections to other trees.


The bulletproof method to keep your trees safe from diseases is to practice control measures. Ensure you disinfect and spray fumigants in the soil quarterly. Also, remove any dead twigs and branches. Look out for discoloration of leaves too. If you notice an infestation of the tree by pests, try using pesticides to kill the pests. You can also consult your local agricultural forest officer on the appropriate measures to take.