Problems With Lemon Trees

Although most lemon tree problems are not life-threatening, it is important to understand their signs and symptoms before the tree is seriously damaged. Lemon trees, though hardy, still suffer from the same diseases and insects that afflict other citrus fruit, such as orange trees. To prevent damage to the tree and its fruit, it is always best to act early.

One common problem for lemon trees is the citrus tristeza virus. Each strain of the virus varies in severity, but common symptoms include pitting in stems, a loss of rootstock, a smaller yield in lemons and--in extreme cases--death of the tree. Aphids, most commonly the citrus aphid, carry the virus from tree to tree. This aphid was introduced to Florida in 1990s, causing a major increase in citrus tristeza virus deaths among the state's citrus trees, according to the University of Florida, Some lemon trees serve as asymptomatic hosts for the virus, acting as a reservoir for aphids to pick up the disease.

Another problem that afflicts lemon trees is root rot. Also known as brown rot, this disease manifests as dark, hard patches all over the tree's trunk. Another distinguishing characteristic of root rot is a viscous substance that oozes from these hardened sections. As root rot progresses, the bark will dry out, crack open and the sections affected will die. Root rot also can affect the tree's leaves and its lemons, as they will turn brown and rot off.

The citrus whitefly is a common pest to the lemon tree. Most often it affixes itself to the underside of the leaf where it gets its sustenance. Like some other pests that affix themselves well to the tree, the citrus whitefly will fly off if the branch is shaken. The citrus whitefly used to be the top pest affecting lemon trees, but it has since fallen below the snow scale and some others, as noted by the University of Florida. The whitefly damages the tree by sucking out its sap and excreting a fungus harmful to the tree.