As with the other Gymnosporangium rust fungi that occur in Ohio, G. clavipes alternates between two very different types of plant hosts. The fungus infects several species in the Juniperus genus including J. communis, J. horizontalis, J. sabina, J. scopulorum, and J. virginianae which is also known as the Eastern red cedar from whence the "cedar" name often appended to the disease name is derived. On junipers, the fungus produces spheroid twig cankers from which spores are released that infect plants in the rose family (Rosaceae). The stem cankers on juniper can become perennial meaning the cankers will continue to enlarge and release spores for several years. The cankers may also cause stem dieback on juniper.

Spores released from the juniper cankers infect rosaceous hosts in the spring as new leaves and flowers are emerging. The fungus is capable of infecting over 480 rosaceous plant species in 11 genera including quince, crabapples, pears, and serviceberries; however, infections are most apparent in Ohio on hawthorns. In most cases, fungicide applications are not warranted in the landscape, but if stem dieback becomes a perennial problem, or where fruit infections, particularly of hawthorns, are severe and result in unwanted tracking of orange-colored spores into houses, preventive fungicide sprays in the spring may be an option.

There are actually several types of rusts on turfgrass that can be caused by a number of different fungi including: black stem rust (Puccinia graminis), crown rust (P. coronate), leaf rust (Uromyces dactylidis), and yellow stripe rust (P. striiformis). Yellow flecks on the leaf blades are the first signs of rust disease on turfgrass. The yellow flecks enlarge which cause the leaf epidermis to rupture and release yellow-orange powdery spores. These fungal spores easily get on shoes, mowers, and pets but are not harmful to humans or animals. Rust infections seldom cause grass plants to die; however, Joe noted that the occurrence of rust on lawns this year is unusually early so season-long damage may be more severe.

Brown patch on turf-type tall fescue is produced by the fungus, Rhizoctonia solani. Symptoms of the disease are highly variable. On lawns, affected areas appear as large irregularly shaped circles 2-3' in diameter, or as a general thinning of turfgrass. Leaf lesions are irregularly shaped with grayish-brown tissue bounded by dark brown margins. The brown patch fungus occasionally produces white mycelium growth in the turfgrass canopy that may be mistaken for the mycelium of dollar spot or pythium blight. Brown patch may occasionally kill turfgrass plants; however, turfgrass mortality can be greatly reduced if the disease is properly managed

Management of both diseases focuses on applying good turfgrass cultural practices. These include: maintaining a good turfgrass fertility program to promote healthy turfgrass growth; avoiding moisture stress, but also avoiding evening irrigation; raising the lawn mower cutting height to promote deep root development; and avoiding soil compaction. Over-seeding with cultivars that have some resistance to these diseases should be considered for lawns with a consistent history of disease infection. Check the National Turfgrass Evaluation Program for information on cultivar susceptibility by visiting the following web address: http://www.ntep.org/ .