Take All Patch
Causal Agent
Gaeumannomyces graminis var. avenae
What is Take All Patch?
Take-All Patch is a turf disease that affects the roots of grass. It initially appears as small, light brown dead patches on turf and once established, can continue to spread throughout the year. Grass that is stressed by take-all patch appears bronze to reddish brown and then fades to a dull brown.
What are the Symptoms of Take All Patch?
Symptoms of Take All Patch include:
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Small, light brown dead patches on turf. Once established, the patches will continue to spread throughout the year. In some cases, patches may appear briefly and cease to spread.
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Stressed grass appears bronze to reddish brown and then fades to a dull brown.
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During winter affected patches turn grey.
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In pure Bentgrass stands a circular or ring-shaped dead spot occurs.
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Patches may enlarge (up to 15cm a year) to reach diameter of 1m or more.
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Affected patches do not usually heal rapidly and the centres are invaded/ colonised by Fescue and weeds.
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In mixed stands, the Bentgrass appears yellow-brown to brown, leaving a thinned overall stand dominated by Wintergrass or Fescue.
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Stolons, rhizomes, roots and bases of shoots become dark brown to black before they are killed.
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Less severely infected tissues often bear dark strands of mycelium oriented primarily parallel to the root axis.
When does Take All Patch occur?
The general conditions that favour take-all patch disease include:
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Severe during cool, wet years and in poorly drained turf.
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Greatly enhanced on turfgrasses grown in soils with high pH.
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Increasing acidity tends to suppress this disease.
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Soil conditions favouring the disease include, light texture, low organic content, low or unbalance fertility, soil pH above 5.5.
What turfgrasses are especially susceptible to Take-All Patch?
Bentgrass - particuarly golf greens within 2 years old. It also infects older Couch greens.
What can I do to manage or control Take All Patch?
Management practices that can help control or reduce instances of Take All Patch include:
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Use acidifying fertilisers.
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Apply moderate to high levels of phosphorous, potassium and minor elements where these nutrients are depleted from the soil.
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Improve drainage of turf.
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When liming apply the coarsest grades of lime to avoid rapid changes in pH.
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Removal of diseases patches and resodding where small areas are affected.
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Preventative systemic fungicide applications.