Answer: While all trees will eventually die of old age, I know of several lemon trees that are close to 100 years old so I think your tree will continue to produce lemons for many years to come. If the skin on the fruit is blotchy, it could indicate a scab disease. I can't really diagnose the problem without seeing it so it would be to your advantage to take a few of the affected fruit to your local cooperative extension office for positive diagnosis and control options. The closest extension office I can find is: University of California extension, 4800 E Cesar E Chavez Ave, Los Angeles - (323) 260-2267.
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