Q.
I have a ‘Eureka’ lemon tree with a branch or two that are dying. Is this
borers?
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| Lemon tree with single branch dying back. |
A. Probably not borers but a disease. Look for sap near the location where the branch died.
Single Branch Dieback of Lemon Most Likely Shoot and Twig Dieback Disease
Branch dieback in citrus, particularly lemon, is very confusing. It is not
likely to be a borer problem. Most likely it is a disease issue called “shoot and twig dieback” of citrus. A lot of federal funding went to California to
answer a branch dieback disease questions for homeowners and commercial growers,
with lemon branch dieback found to be quite common.
If it were me, I would cut the dead
branches back and eliminate the dead branch to a place where it was healthy and
growing in the direction I wanted. As a precaution, I would sanitize the
pruning shears with undiluted 70-90% ethyl alcohol before and after each branch
removal. Treat the fresh cuts with copper sulfate (Bordeaux mix) as a
precaution.