P-Z - Guide for the Management of Turfgrass Diseases

P to Z - Guide for the Management of Turfgrass Diseases.

Note: Grass types listed in capital letters have been observed to be especially susceptible to the pathogen.

Disease: Pink Patch5 (Limonomyces roseipellis).

• Susceptible Turfgrass: FINE FESCUE, PERENNIAL RYEGRASS, Bent grasses.
• Season: Spring & Fall/Autumn.
• Maintenance Practices: Follow balanced fertilisation program.
• Fungicide/Nematicide - Active Ingredient: Mancozeb, Flutolanil.

Disease: Pink Snow Mould/Fusarium Patch (Microdochium nivale).

• Susceptible Turfgrass: Bluegrasses, Bent grasses, Fescues, and Ryegrasses.
• Season: November-April - North America.
• Maintenance Practices: 1) Avoid excessive late fall fertilising; 2) Rake leaves and mow short; and 3) Control drifting snow.
• Fungicide/Nematicide - Active Ingredient: Triadimefon, Fenarimol, Iprodione3, Mancozeb, Azoxystrobin, Pentachloronitrobenzene, Thiram, Thiophanate-methyl3, Vinclozolin, Cyproconazole,

Disease: Powdery Mildew (Erysiphe graminis).

• Susceptible Turfgrass: KENTUCKY BLUEGRASS, Fine Fescue.
• Season: July-October - North America.
• Maintenance Practices: 1) Reduce shade; 2) Increase air circulation by removing surrounding vegetation; and 3) Use resistant Kentucky bluegrass varieties.
• Fungicide/Nematicide - Active Ingredient: Triadimefon, Fenarimol, Propiconizole, Cyproconazole, Myclobutanil.

Disease: Pythium Blight (Pythium aphanidermatum, P. graminicola).

• Susceptible Turfgrass: BENT GRASSES, ANNUAL BLUEGRASS, PERENNIAL RYEGRASS, Kentucky Bluegrass.
• Season: June-September - North America.
• Maintenance Practices: 1) Improve soil drainage; 2) Increase air circulation by removing surrounding vegetation; 3) Avoid mowing wet grass; and 4) Avoid excess watering.
• Fungicide/Nematicide - Active Ingredient: Chloroneb, Etridiazole, Propamocarb, Metalaxyl, Fosetyl-Al, Mancozeb, Aluminum tris, Azoxystrobin

Disease: Pythium Root Rot (Pythium).

• Susceptible Turfgrass: ANNUAL BLUEGRASS, BENT GRASSES.
• Season: Spring & Fall/Autumn.
• Maintenance Practices: 1) Improve soil drainage; and 2) Increase mowing height.
• Fungicide/Nematicide - Active Ingredient: Metalaxyl, Propamocarb Apply Oct-Nov (North America), water in thoroughly. Azoxystrobin.

Disease: Red Leaf Spot (Drechslera erythrospila).

• Season: June-September - North America.
• Susceptible Turfgrass: BENT GRASSES.
• Maintenance Practices: 1) Remove clippings; and 2) Fertilise to maintain vigor.
• Fungicide/Nematicide - Active Ingredient: Iprodione3, Vinclozolin3, Chorothalonil.

Disease: Red Thread (Laestisaria fuciformis).

• Susceptible Turfgrass: PERENNIAL RYEGRASS, FINE FESCUE, Bent grasses, Annual Bluegrass, Kentucky Bluegrass.
• Season: All seasons.
• Maintenance Practices: 1) Follow balanced fertilisation program; 2) Promote growth by aeration; and watering, etc.
• Fungicide/Nematicide - Active Ingredient: Vinclozolin 3, Flutolanil, Chlorothalonil, Cyproconazole, Thiophanate-methyl3, Mancozeb, Triadimefon, Propiconizole, Iprodione3, Myclobutanil, Azoxystrobin.

Disease: Rhizoctonia Blight/Brown Patch (Rhizoctonia solani, = Thanatephorus cucumeris)6.

• Susceptible Turfgrass: TALL FESCUE, BENT GRASSES, PERENNIAL RYEGRASS, Kentucky Bluegrass, Fine Fescue.
• Season: July-August - North America.
• Maintenance Practices: 1) Avoid excessive nitrogen fertilisation; 2) Increase air circulation by removing surrounding vegetation; and 3) Avoid excessive watering.
• Fungicide/Nematicide - Active Ingredient: Anilizine, Chlorothalonil, Mancozeb, Maneb, Propiconizole, Pentachloronitrobenzene, Thiram, Triadimefon, Thiophanate methyl3, Cyproconazole, Iprodione3, Myclobutanil, Azoxystrobin.

Disease: Rust (Puccinia spp.).

• Susceptible Turfgrass: PERENNIAL RYEGRASS, KENTUCKY BLUEGRASS.
• Season: August-October - North America.
• Maintenance Practices: 1) Avoid nitrogen deficiency; 2) Use resistant varieties of Kentucky Bluegrass and Perennial Ryegrass; and 3) Water if dry, promote growth.
• Fungicide/Nematicide - Active Ingredient: Mancozeb, Propiconizole, Cyproconazole, Chlorothalonil, Triadimefon, Fenarimol, Myclobutanil.

Slime Moulds (Myxomycete).

• Susceptible Turfgrass: All Turfgrasses.
• Season: August-September - North America.
• Maintenance Practices: Remove mechanically by mowing or raking.
• Fungicide/Nematicide - Active Ingredient: Mancozeb.

Disease: Snow Mould - see Gray Snow Mould and Pink Snow Mould.

Disease: Stripe Smut (Ustilago striiformis).

• Susceptible Turfgrass: KENTUCKY BLUEGRASS, Bent grasses.
• Season: Spring & Fall/Autumn.
• Maintenance Practices: 1) Avoid drought stress; 2) Avoid excess nitrogen; 3) Use resistant varieties of Kentucky Bluegrass.
• Fungicide/Nematicide - Active Ingredient: Propiconizole, Triadimefon, Myclobutanil, Cyproconazole Note: Apply extra water for crown penetration. Apply in late fall or early spring.

Disease: Summer Patch4 (Magnaporthe poae, formerly Phialophora graminicola).

• Susceptible Turfgrass: ANNUAL BLUEGRASS, KENTUCKY BLUEGRASS, Fine Fescue.
• Season: June-August - North America.
• Maintenance Practices: 1) Avoid low mowing and thatch buildup; 2) Maintain soil pH between 6 & 7; 3) Light, frequent watering during dry periods to reduce heat stress; 4) Use slow-release nitrogen; 5) Use Kentucky Bluegrass and Perennial Ryegrass mix; and 6) Avoid compaction.
• Fungicide/Nematicide - Active Ingredient: Fenarimol, Triadimefon, Propiconizole, Cyproconazole, Myclobutanil, Azoxystrobin. Note: Materials must be applied preventively. Thiophanate-methyl. Note: Thiophannate-methyl works best as a curative application.

Disease: Take-all Patch (Gaeumannomyces graminis).

• Susceptible Turfgrass: BENTGRASSES.
• Season: Spring & Fall/Autumn.
• Maintenance Practices: 1) Use acidifying fertilizers to lower pH; 2) Avoid heavy rates of lime; 3) Remove patches and resod; and 4) Avoid excess nitrogen fertilisation.
• Fungicide/Nematicide - Active Ingredient: Fenarimol., Triadimefon, Propiconazol, Azoxystrobin.

Disease: Typhula blight - see Gray Snow Mould/ Tiphula Blight.

Disease: Yellow Patch (Rhizoctonia cerealis).

• Susceptible Turfgrass: Bluegrasses, Bent grasses.
• Maintenance Practices: 1) Reduce excessive thatch; 2) Avoid excessive watering; and 3) Improve soil drainage.
• Fungicide/Nematicide - Active Ingredient: Flutolanil, Azoxystrobin.

Yellow Tuft/Downy mildew (Sclorophthora spp.).

• Susceptible Turfgrass: Bent grasses.
• Season: Spring & Fall/Autumn.
• Maintenance Practices: Improve soil and surface drainage.
• Fungicide/Nematicide - Active Ingredient: Metalaxyl, Fosetyl-Al, Aluminum tris.

.

Products containing these active ingredients are listed in Trade Names for Turfgrass Fungicides and Nematicides. Read the product label to see if it is labeled for the disease of concern. The degree of control may vary with different products.

Continued or sole use of these materials may favour buildup of resistant fungal population.

Necrotic ring spot and summer patch are known to cause symptoms once attributed solely to Fusarium blight.

Pink patch is a distinct disease from red thread. There are few fungicides specifically registered for control of pink patch

Another fungus, Rhizoctonia zeae, is also capable of causing brown patch-like symptoms on bluegrass and bentgrass. Benzimidazole fungicide (Thiophanate-methyl) is not effective against this pathogen.