Disease & Fungus

Leptosphaerulina spp Leptosphaerulina leaf blight, a fungal disease, can affect a wide range of turfgrass species predominantly cool season varieties, causing aesthetic damage and reducing overall turf health. This guide provides information on identifying, understanding, and managing Leptosphaerulina leaf blight in your lawn. The Cause and Susceptible Turf The culprit behind this disease is a fungus belonging to the genus Leptosphaerulina. Several species within this genus can cause leaf blight, but the most common ones associated with turfgrass include L. americana,…

Gaeumannomyces graminis var. avenae Take all Patch is part of the ERI group of fungi. Mainly found on newer Bentgrass greens. Initially small, light-brown dead patches appear on turf resembling Fusarium. Once Take all Patch is established, the patches continue to grow throughout the year, causing the turf to appear a bronze to red colour and fade out to brown. In cooler times of the year the patches can be grey. Patches may grow to 15 cm per year and…

Slime Mould affects all turfgrass species and can take on various appearances from a dusty spore to yellow spheres like caviar. It can smother grass blades, turning them grey, pink, purple, white or yellow. The affected turf forms patches up to 60 cm in diameter and it grows outwards, yet there is no immediate damage to the turfgrass. Slime Moulds are not plant parasitic. The fruiting moulds can become that thick on the leaf that the photosynthetic ability of individual…

Ophiosphorella (formally Leptosphaeria) herpotricha, O. korrae, and O. narmari. Spring Dead Spot (SDS) is part of the ERI Family of diseases. Symptoms can appear in lower soil temperatures when growth is slow to dormant, depending on the season, as early as late Autumn. Traditionally it was found often in late winter and spring, when turf resumes its growth and will present circular, bleached dead patches. Patches are often also visible in autumn and in winter. The patches can range from a few…

Puccinnia & Uromyces species Rusts are fungal diseases that involve many different strains and affect a wide variety of plants, including grasses. Most warm and cool season turfgrass species are susceptible to rust diseases; the turf health is irrelevant as it will also attack a healthy plant. Orange spores appear underneath the leaves, making Rust easy to identify. The spores, coloured orange to red, spread across affected grasses. These irregular patches will appear on the leaves, and as the disease…

Pythium spp. Pythium blight first appears as small, irregularly shaped spots ranging from 12 mm to 100 mm in diameter. Leaves appear water-soaked in appearance at first, then shrivelled. Diseased patches fade to a light-brown or grey colour. Groups of spots frequently join together. At times, the shape of the affected areas may resemble elongated streaks. Both the presence and pattern of these streaks seem to be determined by the flow or presence of surface water. Pythium Blight thrives during…

Bipolaris spp. Drechslera spp. and Exserohilum spp. Black or White Helminthosporium (Helmo) is a common black or white leaf spot disease which is actually caused by 3 different species of fungi (listed above). The disease cycle is generally short, but can cause some unsightly damage very quickly. ‘Helmo’ is caused by a common and serious group of diseases, attacking a diverse range of warm and cool season turf grasses. Helmo can develop at a wide range of temperatures from 3°C and 30°C, with optimal…

Microdochium (Microdochium nivale) (formally Fusarium) Patch is found in warm season and cool season grasses like wintergrass, bent grass, fescue, ryegrass, Kentucky Bluegrass and low mown Kikuyu in cooler climates. Initially round patches appear as small, water-soaked spots less than 5 cm in diameter. They then change in colour from orange brown to dark brown and finally to a light grey. Some spots may enlarge but are usually less than 20 cm in diameter. On low-cut turf a halo-like “smoke…

Fairy Ring is caused by the Basidiomycetes, group of fungi of which there are at least 50! species known to cause it. It is also indiscriminate to turf varieties; all species of turf can be affected by it. Fairy ring tends to occur most often in soils and turf grasses with no to little nutritional inputs, heavy thatch layers and low soil moisture. Unlike other diseases fairy ring fungi does not directly infect the grass, instead opting to affect the soil…

Also referred to as Couchgrass Decline, turf grass symptoms of ERI disease start by thinning out of the surface and can include straw-coloured patches that range in size from 30 cm to 1 metre in diameter. Ectotrophic root-infecting fungi (ERI fungi) are a factor in causing patchiness and poor root health in couch grass. The term ‘ectotrophic’ means these fungi grow over the root surface before they penetrate into the inside of the root. ERI fungi involves a number of fungal…

Dollar Spot, caused by the fungus Clarireedia jacksonii (formerly Sclerotinia homoeocarpa), Dollar spot is a common and persistent disease in Australian lawns, particularly during mild, moist periods in spring and autumn. It affects both cool-season and warm-season grasses, including couch, kikuyu, ryegrass, and bent grass. Signs and Symptoms of Dollar Spot Starts off as small circular spots 2-6cm wide. Hour glass shaped legions on the leaf. In longer mown turf, patches can merge together into larger patches. Can present Mycelium,…

Brown Patch (Rhizoctonia Solani) or commonly called "Rhizo" Brown Patch disease occurs on cool season and warm season turf grass species. Identification of Brown Patch Circular or irregular patches from 5cm to over 1m in diameter. Can have smoke ring or halo affect during "peak" fungal activity. warm season grasses can just look "weak" and thin particularly during dormancy or stressed periods. it can present with Mycelium- but don't just rely on this as your identification, as a lot of…

Colletotrichum spp. Anthracnose is a group of fungal diseases targeting both the roots (basal rot) and leaves (foliar blight) of turf — especially when conditions are warm, humid, or when your lawn's under stress. will mainly target low mown areas such as golf greens. The grass types most susceptible are; Poa, Bent, Fescue, Kentucky Bluegrass and couch. What causes anthracnose; Low levels of fertility - especially Nitrogen. Lower mowing heights and scalping. Warm & humid conditions Prolonged periods of leaf…