Ryan Iacovacci just picked up 18 Meyer's Lemons for the bash at Ella's, and I gave him a quick tutorial on spotting the 'Citrus Greening' disease that has ravaged many/most citrus trees here in south Tampa. A few months ago I attended a presentation about it at the Tampa Rare Fruit Council. The easiest way to spot it is to look at the leaves....a citrus tree in need of zinc or iron or manganese or magnesium can have varying leaf patterns of yellow....they are SYMMETRICAL.....the patterns of 'Citrus Greeding' are ASYMMETRICAL. See the link. A sick tree is easy to spot...lots of dead branch tips, then entire branches. The tree can die in less than a year. The bacteria is spread by a psillid (sp?) insect. Best to cut down the tree and BURN the branches. I'd love to hear from folks if it is their area too.....in my travels to assist my Dad I saw entire orchards in south Florida dying or dead from it. So far, my own root, probiotically grown citrus trees here in south Tampa are symptom free despite it being epidemic in south Tampa. It is a global citrus disease now rampant in Florida.

http://www.crec.ifas.ufl.edu/extension/greening/symptoms.shtml