Symptoms of dogwood anthracnose on flower bracts, caused by the fungus Discula destructiva (Photo credit: Robert L. Anderson, USDA Forest Service, Bugwood.org) (Photo credit: Robert L. Anderson, USDA Forest Service, Bugwood.org).

Disease Pest Identification

Identifying plant disease in the garden, lawn, and landscape begins by investigating the host plant and looking for clues. The following resources provide information, many through pictures, that aid in identifying the disease pest.

Garden

Tomato spotted wilt virus on tomato (Whitney Cranshaw, Colorado State University, Bugwood.org).

• Disease Problems of Vegetables by Region
• Fruit Disease Pests by Region

Lawn

Signs of dollar spot on St. Augustine grass, caused by the fungus Sclerotinia homoeocarpa (Photo credit: Division of Plant Industry Archive, Florida Department of Agriculture and Consumer Services, Bugwood.org).

• Plant Disease Diagnostics - Turf (Yard and Garden Line, University of Minnesota Extension)

• Turfgrass Diseases in Georgia: Identification and Control (University of Georgia Cooperative Extension)

Landscape

Symptoms of Cytospora canker on spruce caused by the fungus Cytospora spp (Photo credit: Joseph O'Brien, USDA Forest Service, Bugwood.org).

• Tree and Shrub Disease Problems by Region

Image Resources

Pictures can be an important tool in helping you diagnose problems in the landscape.

• Oregon State University Image Index (Oregon State University Extension) provides a searchable index of plant disease images

• Integrated Pest Management Images (ipmimages.org^[1]) offers an extensive collection of images on many topic, including diseases, insects, and other pests

• Invasive Diseases (www.invasive.org^[2]) documents many of the most troublesome diseases that originated in other parts of the world

Local Diagnostic Laboratories

If you cannot identify your disease problem with the resources provided, you may be able to submit information to your state diagnostic plant laboratory using:

• University Plant Diagnostic Clinic Web Addresses (Maintained by the American Phytopathological Society)

Fungicide Use and Products

While plant diseases may be caused by a number of organisms, such as bacteria, fungi, viruses, or phytoplasmas, only fungal plant diseases can be effectively controlled through the use of chemical pesticides. A fungal pesticide is called a fungicide. Fungicides and their use vary by state.

Fungicides for Disease Control

• Oregon State University Extension: Fungicides for Disease Control in the Home Landscape (Oregon State University Extension) is an up-to-date article on fungicide use; explains the categories of fungicides generally available to the home gardener, including major common names, notes on uses, and cautions (Most of the information is broadly applicable but some is specific to the Pacific Northwest)

Fungicide Chemical Information

The fungicide label is a legal document that provides instructions for proper fungicide usage. All pesticide containers are required by law to have a pesticide label. Another important document, the material safety data sheet (MSDS), informs the user about the chemical's physical properties and safe work practices. Label and MSDS information can also be found by using the Web sites listed below. Some of these sites may require you to register free of charge before using.

• Home Use Pesticide Database (Colorado State Extension)

• Pesticide Information (Center for Urban Ecology and Sustainability, University of Minnesota)

• CDMS Agro-chemical Database (Crop Data Management Systems Inc.)

• Greenbook.net (Greenbook, Vance Publishing Corporation) - use the search feature to find labels and material data safety sheets for insecticides

Find State Regulatory Data for your state:

• KRSNetwork (Kelly Registration Systems Inc.)

-User hint: Under the "Our Services" tab, scroll down to find the Information Resources, then State Regulatory Data section, and select a state from the drop-down menu.

Credits

1. ↑ is a joint project of the Bugwood Network, CSREES Southern IPM Center and the Southern Plant Diagnostic Network The University of Georgia - Warnell School of Forestry and Natural Resources and College of Agricultural and Environmental Sciences - Department of Entomology
2. ↑ Invasive.org is a joint project of the Bugwood Network, USDA Forest Service, and USDA APHIS PPQ The University of Georgia - Warnell School of Forestry and Natural Resources and College of Agricultural and Environmental Sciences - Department of Entomology