What is Iron Chlorosis?

The temperatures in August haven’t turned much cooler, yet some trees may look like fall is approaching. If your tree’s leaves are turning yellow or falling off, your tree might have iron chlorosis.

Iron Chlorosis: Defined

Iron chlorosis is a deficiency of the nutrient iron in trees—it’s kind of like having an anemic tree. Iron chlorosis develops when trees struggle to bring in essential nutrients from the soil. This problem is common in Utah.

Soils in Utah have a good level of iron. So, why do trees’ roots struggle to soak it up? The answer is simple: Utah’s clay-like soil is alkaline (a pH level of 7 or higher), so chemical reactions in the soil cause the iron to harden, making it inaccessible to tree roots. In order to thrive, trees need their iron in a form that is easy to absorb.

Identifying Iron Chlorosis

Iron chlorosis plagues Utah plants, especially Autumn Fantasy and Autumn Blaze Maple trees. Tree leaves turn yellow while the veins of the leaves retain a dark green color. The plant life hungers for chlorophyll, the green pigment essential in photosynthesis.

If the leaves remain deprived of chlorophyll, they eventually die and fall off the tree. All or part of the tree can be affected by iron chlorosis.

Often, trees affected by iron chlorosis still have green, healthy-looking sections along with the defoliated parts. Some trees in the early stages of iron chlorosis have evenly dispersed yellow-green leaves with brown, shriveled leaf edges.

Treating Iron Chlorosis

Fortunately, iron chlorosis is treatable. Trees develop iron chlorosis because they are not receiving iron from the soil, so in the early stages of iron chlorosis,  soil treatments are recommended. If the tree is in the late stages of iron chlorosis, it should be treated with injections of iron directly into the tree trunk.

Trees can receive these treatments in early spring or fall. Iron chlorosis treatments are difficult to do properly; they require extensive training and a practiced hand, so only qualified experts like Stewart’s arborists can do them properly.

If you think your tree has iron chlorosis or other problems, call or text us at 801-226-2261, and you can talk to an arborist free of charge.


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