Chlorotic condition of oak tree

The foliage of most trees is a deep shade of green. When leaves deviate from this, it could be the result of an insect, disease, or environmental condition that is impacting the tree. When the leaves of acid-loving plants like pin oak, red oak, or holly are more yellow, this is known as a “chlorotic” condition. In most cases, this is the result of the plant growing in a soil with a basic pH, where the essential element, iron, is unavailable. An oak with chlorotic condition lacks dark green leaves. Iron is necessary for the green chlorophyll that leaves need to get their energy from the sun; when this element is absent, leaves have a yellowish, “chlorotic,” cast to them, and the plant suffers from a lack of energy.

Credit: frederick.forestryboard.org - Mike Kay

Conditions that limit air movement in the soil, such as too much water, compaction, and impervious material covering the soil, can also result in chlorotic conditions.

The loss of topsoil can also trigger iron chlorosis, especially if the topsoil contained a lot of organic material and had an acidic pH. To remedy this condition, the soil pH can be elevated by aeration, or with amendments like lime, iron chelate, or another iron source.

The best solution, however, may be to check the pH of the soil and planting well-suited trees or shrubs for the site.

Article by FCFCDB member

Nature Note for 9/11/2016