Linden trees are susceptible to fungal infections that cause cosmetic to severe damage. Knowing what to look for is only half the battle. In addition to visual signs, familiarize yourself with effective control methods to prevent or deal with infection. Through appropriate care, your linden trees can avoid illness and remain vigorous in your home garden.
Through proper maintenance, your linden trees will remain healthy and prepared to resist or fight off fungal infections. Weakened trees are more vulnerable to fungal problems than vigorous trees. Plant lindens in locations that provide good air circulation and full sunlight. Lindens prefer moist, well-drained soil with good fertility, according to the North Carolina State Cooperative Extension Service.
Fungal infections like anthracnose attack a wide variety of shade trees including lindens. Fungi that have overwintered on plant debris are transported by wind or rain to new leaf growth on linden trees. In wet conditions and cool temperatures, the fungi germinate and infects leaves and stems, according to the University of Illinois Extension IPM.
Symptoms and Damage
On linden trees, anthracnose disease results in the presence of leaf spots and cankers. Leaf spots appear in a light brown color on leaf surfaces and may display darker hued borders, according to the University of Illinois Extension IPM. Additionally, cankers or lesions of dead tissue form on twigs. Infection may lead to diminished tree health and severe defoliation, particularly in extremely moist conditions favored by fungi.
For natural control of fungal disease on linden trees, remove and destroy affected plant parts to prevent the localized spread of disease as well as the sporadic spread of pathogens to another plant, according to the University of Illinois Extension IPM. Avoid waterlogged soil and overhead irrigation as excessively wet plant parts provide the ideal environment for fungal germination. Sanitize pruning shears after every cut and with each use on a different tree to prevent disease transfer.
Though the use of chemical control is usually not necessary, for severely infected linden trees, apply an appropriate fungicide. For anthracnose control, fungicides with the active ingredient benomyl, copper hydroxide or lime sulfur are effective, according to the Iowa State University Extension. Though fungicides are generally available for home application, contact a licensed professional or your local county extension agent if you are in need of application assistance.