The genus Ficus, Latin for fig, is a member of the family Moraceae. It contains over 800 species of woody trees, shrubs, or vines. Some cultivated varieties can produce edible fruit or possess ornamental value. All species of ficus can become susceptible to pest problems and diseases. Some diseases can be caused by specific fungi.
The Ficus family has a large number of species, and each has its own distinctive characteristics. The Ficus benjamina, or common weeping fig, can grow as tall as 60 feet. It is hardy to U.S. Department of Agriculture (USDA) zones 10b to 11 and prefers full sun to part shade and well-drained soil. Ficus carica is best grown in USDA zones 8 to 10 in rich, moist, well-drained soil. It requires full sun to part shade.
When grown outside, the weeping fig grows large and rather quickly with a fruit that stains if it lands on cars and sidewalks. These trees are best in park settings or landscapes with large open areas. They can be planted in yards but pruning must be done to control size. The Ficus carica is used as a deciduous shrub that is 10 to 15 feet tall, or a small tree 15 to 30 feet tall in garden landscapes. Most ficus are used as indoor houseplants.
Several diseases are caused by fungi that affect different species of ficus: aerial/web blight, caused by Thanatephorus cucumeris/Rhizoctonia solani; anthracnose, caused by Glomerella cingulata/Colletotrichum gloeosporoides; and Cercospora leaf spot, caused by Cercospora fici, Cercospora spp.
Symptoms of aerial/web blight appear first on the leaves, causing a yellowing of the leaf. In time, the top of the leaf turns a grayish-white color with the underside becoming enveloped in the fungus, leaving brown webbing. The webbing holds the leaf onto the tree but also transfers the fungus onto the branch or twig. The twigs will die, and if there is fruit, it will become covered by the fungus webbing. The fungus can reproduce by forming small black spots on the webbing. The fungus can live a long time in plant debris or in the soil.
Anthracnose shows on the leaves as recessed spots with brown edges. Eventually the entire leaf turns brown and falls off. The fruit becomes soft and rots and can fall off the tree. It can also become covered by the webbing of the fungus and remain on the tree as a source of new infection.
Leaf spot can develop quickly during rainy periods. Spots first appear on the leaves as reddish-brown. The spots will grow bigger and the centers will become tan with a yellow edge. Wounds can also develop on the leaf tips.
Control & Management
Aerial/web blight, management involves good pruning practices to remove infected areas and to increase air movement around the leaves. The plant or tree should be watered low at the base so as not to wet the leaves, and removal of all infected fallen diseased debris is important. No EPA chemical treatment is available for this fungus as of 2010.
For anthracnose, it is important to remove all fallen fruits and leaves to reduce survival of the fungus from season to season. No EPA chemical treatment is available as of 2010.
Leaf spot management is almost identical to aerial/web blight management. Plants or trees infected with leaf spots should be watered low to avoid wetting the leaves, and all infected fallen diseased debris should be destroyed. No EPA chemical treatment is available as of 2010.