Canker

Canker is a term used for diseases that produce sunken, necrotic areas on woody plant tissues, most commonly stems and branches, as well as a name for aphthous ulcers in the mouth. In plants, cankers are usually caused by fungal or bacterial pathogens and can lead to girdling and death of affected limbs. They are influenced by environmental stress, wounding, and plant susceptibility.

Symptoms include depressed, discolored, cracked, or oozy lesions; over time bark may crack and the limb may die beyond the lesion. Diagnosis often relies on symptom observation and, if needed, lab culture or DNA testing. Management emphasizes removing infected tissue, sanitizing tools, ensuring tree vigor through proper watering and fertilization, avoiding wounding, and, when feasible, applying appropriate fungicides to protect healthy tissue. Severe cankers may be unrecoverable and require removal of the affected limb.

Canker sores, or aphthous ulcers, are small, painful lesions inside the mouth that are not contagious. They typically heal in one to two weeks. Triggers can include trauma from biting, stress, hormonal changes, nutritional deficiencies, or certain medicines. Treatment focuses on pain relief and oral hygiene, using topical anesthetics, antiseptic mouthwashes, and protective pastes. Recurrent cases may warrant medical evaluation for underlying conditions.