Nutritional disorders in trees
Symptoms of nutrient disorders usually appear as mirror-image patterns on either side of the leaf mid-vein. (Phosphorus disorder symptoms are the exception.)
Symptoms of fungal diseases or pests appear as irregular patterns and distributions.
Use this key to determine some common nutritional disorders in plantation trees. Work through the key from left to right to identify the nutrient disorder in your tree.
|Affected area||General symptoms||Deficiency||Symptoms|
|Symptoms appear first of more prevalent on mature leaves||Leaves discoloured evenly||Nitrogen (N)||Leaves pale green to yellow|
|Phosphorus (P)||Leaves green with reddish blotches or uniformly purple to red|
|Leaves discoloured in patterns||Magnesium (Mg)||Distinct interveinal chlorosis (discolouration), often bright yellow|
|Potassium (K)||Leaves with marginal burns often expanding to interveinal areas|
|Symptoms appear first or more prevalent on expanding leaves||Reduced growth or dieback in the shoot apex||Boron (B)||Enlarged nodal regions; slow growth; sometimes apical death; proliferation of lateral shoots; interveinal crinkling in younger leaves; corky abaxial veins or malformed margins|
|Calcium (Ca)||Nodes normal; apical shoot death; leaves buckled due to reduced growth of margins; leaf expansion often stunted|
|No dieback in the shoot apex - leave normal size||Copper (Cu)||'S' shaped stem growth, leaved with irregular or undulate margins, some interveinal chlorosis|
|Sulfur (S)||Leaves pale green to yellow|
|Iron (Fe)||Interveinal chlorosis with sharp borders to green veins|
|Manganese (Mn)||Leaves with marginal or mottled chlorosis; small necrotic bleached or brown spots may appear|
|No dieback in the shoot apex - leave small and crowded||Zinc (Zn)||Developing interveinal chlorosis with hazy borders to green veins|
- Read more about pests, diseases and nutritional disorders in subtropical hardwoods, including symptoms of nutritional disorders in subtropical eucalypts.