Question
I am a farmer in the Bahamas, I have a small crop of key limes, the trees have not been doing well for a long time, they have a black gum on the leaves and trunk, they wither away and die bearing small fruit. Can you recommend treatments,

Thanks,

Tony

Answer
Anthony:
The gum presence on the trunk may represent an injury to the bark. The injury can sometimes be caused by an insect that is boring into the wood. If possible wipe the gum off the stem and look closely below that area. Look for a small hole 1-2mm diameter.  If you like, you are welcome to send me a closeup photo. Be sure to review your image on your computer first- before sending.  To be sure it is in focus. Consider showing some of this gum to folks at your local garden center/nursery where these trees may be sold. These folks may have seen this before and know what it is for sure.

Hope this is a start to your solution.
Steve