Yellow leaves on olive tree: Main causes and solutions

Yellow leaves on olive tree, yellow leaves due to leaden repilo, causes yellow leaves, yellowing leaves on olive tree, olive tree leaves turning yellow — Photo of yellow olive leaves (taken in June)

Various causes can lead to the appearance of yellow leaves on olive tree. Old age, repilo, anthracnose, deficiencies, toxicity… Although the olive tree diseases are the main reason for the yellow and dry leaves, There are different causes that can affect the olive leaves.

Leaves infected by repilo

The repilo del olivo and the lead of the olive tree are the main causes of yellow leaves on olive trees. They produce different yellow spots and the fall of the affected olive leaves. When the trees are not treated properly, the defoliation is intense, being the repilo the main cause of the olive leaves falling. This weakens the trees and negatively affects the production of the olive grove. Excess Nitrogen favors repilo contamination.

Nutritional deficiencies

Different nutritional deficiencies cause olive leaves to show spots and yellow areas of varying intensity.

Finding yellow or dry leaves on olive trees can be useful for us to recognize nutritional deficiencies and carry out a correct fertilization of the olive tree.

When the olive tree is deficient in Calcium (Ca), it affects the tips of the young olive leaves, initially they take on a yellowish-green color, finally turning yellow-orange.
Lack of Iron (Fe) produces symptoms of chlorosis in olive leaves, which show a dull green or yellowish color.
Deficiencies in Zinc (Zn) cause deformities in the shoots and yellowish spots that appear mainly on the edges of olive leaves.
Nitrogen (N) deficiencies cause the leaves to turn yellowish-green.
Deficiencies of Magnesium (Mg), Manganese (Mn) and Boron (B) also produce chlorosis with leaves of yellow olive tree.
Lack of Potassium (K) affects drying the tip and edges of the leaf, especially in older leaves.

Old olive tree leaves

The olive leaves, with approximately 2 years of activity, give up their nutrients to the young structures of the tree. During this process, the olive leaves change their pigmentation from green to yellow, before falling to the ground.

Root asphyxia

With root asphyxia, different soil fungi act and cause significant damage to the root system of the olive tree. As a result, the leaves olive trees turn yellow and eventually the trees can dry out completely.

Motifs of dried olive leaves

The appearance of dry olive leaves can be due to different causes.

Verticillium Dahliae

The olive branches affected by the Verticillium wilt or dry of the olive tree, present their leaves dry and stuck to their branches.

Pest Attack

Pests such as the olive borer can damage branches by cutting off the sap flow, drying out the affected olive leaves.

Exposure to high temperatures

During the burning of the olive branch, it is common for some branches of the nearby olive trees to end up affected by burns, leading to the drying of the leaves, especially when pruning is carried out of the olive tree in high density olive groves.
Once damaged, the olive leaves on the affected branches turn yellow and gradually dry up.

Soil toxicity

The contamination of the land with heavy metals, usually after fertilizing with sludge from wastewater treatment, has caused significant damage to many olive groves.

This toxicity produces a significant loss of leaves to the olive tree, which fall to the ground and favors the trees to stop being productive.

Herbicide application

The herbicides used to control weeds in the olive grove (Glyphosate, MCPA…), can reach some lower branches during its application.The affected olive leaves may dry out, appearing necrotic spots.

Olive leaf fall

Some diseases such as anthracnose or soapy olives can cause significant defoliation on olive branches, with a general drop of green leaves.

Yellow leaves on olive tree