Louisiana Yards and Neighborhoods Common Landscape Diseases Common Landscape Diseases

Diseases in the Landscape Diseases occur on landscape plants when environmental conditions are suitable for pathogens to develop on them. Prevention is the key to the management of disease in the landscape. Diseases occur on landscape plants when environmental conditions are suitable for pathogens to develop on them. Prevention is the key to the management of disease in the landscape.

Powdery Mildew Caused by fungi Spread by wind Favored by high humidity and moderate temperatures Caused by fungi Spread by wind Favored by high humidity and moderate temperatures

Leaf Spots and Blights Caused by fungi, bacteria and algae Spread primarily by wind and splashing water Favored by extended periods of leaf wetness and high humidity Caused by fungi, bacteria and algae Spread primarily by wind and splashing water Favored by extended periods of leaf wetness and high humidity

Anthracnose Caused by fungi Attack all aboveground plant parts Spread primarily by splashing water Favored by extended periods of leaf wetness and high humidity Caused by fungi Attack all aboveground plant parts Spread primarily by splashing water Favored by extended periods of leaf wetness and high humidity

Fire Blight Caused by a bacterium Spread by splashing water, bees and on pruning tools Enters primarily through flowers Prune out infected branches Choose resistant varieties Caused by a bacterium Spread by splashing water, bees and on pruning tools Enters primarily through flowers Prune out infected branches Choose resistant varieties

Root and Crown Rots Caused primarily by fungi, “water molds” and nematodes Spread primarily in water, soil and planting materials Favored by poor drainage and excess moisture Caused primarily by fungi, “water molds” and nematodes Spread primarily in water, soil and planting materials Favored by poor drainage and excess moisture

Viruses Spread primarily by insects, in infected sap and through propagation material Once a plant is infected, there is no cure Spread primarily by insects, in infected sap and through propagation material Once a plant is infected, there is no cure

Turf Grass Patch Diseases Caused primarily by fungi, “water molds” and nematodes Environmental stresses often predispose turf to pathogen attack Follow BMPs for growing and maintaining healthy turf to prevent disease Caused primarily by fungi, “water molds” and nematodes Environmental stresses often predispose turf to pathogen attack Follow BMPs for growing and maintaining healthy turf to prevent disease

Fairy Rings Caused primarily by fungi that produce mushrooms or “toadstools.” These fungi grow on buried wood, tree roots or other organic matter in the soil, not on the grass! Difficult to control; must break up the hydrophobic fungal layer in the soil. Caused primarily by fungi that produce mushrooms or “toadstools.” These fungi grow on buried wood, tree roots or other organic matter in the soil, not on the grass! Difficult to control; must break up the hydrophobic fungal layer in the soil.

Environmental Factors Do not spread from plant to plant Caused by factors such as drought, excess water, nutrient deficiencies or toxicities, etc. Do not spread from plant to plant Caused by factors such as drought, excess water, nutrient deficiencies or toxicities, etc.

Louisiana Yards and Neighborhoods Common Landscape Diseases Common Landscape Diseases