Why does my Orange tree leaves have dark spots on the bottom side/

Question

Orange tree has been bearing orages for 10 or more years. Leaves that have dark spots are discolored yellow and  green. Bottom of leaves has slightly raised dark sploches of various sizes from pin points to 3mm donut shaped. The spots are a medium greenish brown color. I can email a photo if given an email address. I am trying to determine if tree needs some care and what that care would be to relieve this condition. Not all leaves have this discoloration on their bottom.

Answer 1

You tree is dying of a calcium deficiency.  You need to add calcium to the soil.  Either by crushed egg shells or sour milk.  And you will need to do it quickly before the tree actuially dies. -Birdy