Diseases have a negative implication for trees because they may reduce the productivity of the tree or kill it. But do not panic if you notice the signs of disease on the leaves or barks of your trees. The best course of action would be to diagnose the pest or disease that plagues your tree and treat it.
Below is a guide to some of the common tree diseases you are likely to encounter and how to control them
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Anthracnose Disease
Anthracnose is a disease from a group of fungi that attacks parts of a tree including flowers, fruits, leaves, and twigs. This disease is in a wide variety of species in North America but is more prevalent in flowering dogwood and sycamore.
The symptoms of anthracnose vary by the host species and specific pathogen. In many cases, this disease causes premature falling of leaves and leaf blight that results in witches' blooming. Furthermore, parts of the tree that are above ground may be affected, resulting in branch dieback, defoliation, and tree death.
Ideally, apply fungicides to the leaves two weeks before the buds break. You can also inject the trunk with systematic fungicide. If you have dogwood, continue fungicide application throughout the growing season.
Pine Needle Diseases
This group of diseases includes needle rusts, casts, and blights. Needle rusts grow on the needle's surface and do not really cause harm to the needle. On the other hand, needle casts and blight grow inside the needle and cause the needles to shed or die.
The treatment of these diseases is based on the type of disease and the species the disease attacks. Thankfully, these diseases are just unsightly and do not pose a threat to your trees in the long term and may not need treatment. However, for trees that are for ornamental purposes such as Christmas trees, needle diseases may reduce merchantability, so you may need to consider treatment.