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How to Manage Pests
UC Pest Management Guidelines
Turfgrass
Take-All Patch
Pathogen: Gaeumannomyces graminis var. avenae
(Reviewed 6/03,
updated 6/03)
In this Guideline:
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DESCRIPTION OF THE DISEASE
Take-all patch appears as circular or ring-shaped dead areas that range from a
few inches up to 3 feet or more in diameter. Dying bentgrass at the advancing
margins of these areas has a purplish tinge. The roots of the diseased plants
are rotted and have dark strands of mycelium visible on the surface of the
roots. Large black perithecia, which are globular or flask-shaped fungal
fruiting bodies, may be visible with the use of a hand lens. The pathogen
survives in grass debris and living grass plants.
SUSCEPTIBLE TURFGRASSES
Bentgrasses are the most susceptible, but fescues and ryegrasses are also
susceptible to take-all patch.
CONDITIONS FAVORING DISEASE
In California, take-all patch principally occurs in late fall and winter when
air temperatures are 50° to 60°F and soils are wet or moist, but
symptoms may not manifest until the turf is exposed to periods of drought or
heat stress. Soil conditions that favor the disease include light texture, low
organic matter, low or unbalanced fertility, high pH, and high moisture. The
disease may be spread by spores produced by the peritheica, in infested soil
and sod, or by dethatching and aerification equipment.
MANAGEMENT
To prevent the development of this disease, make sure the turfgrass has
adequate soil drainage and fertility.
Cultural Control
Recovery of bentgrass can be slow on closely mowed turf; affected areas can be
resodded if necessary, and some varieties with improved tolerance are
available. Raising manganese levels in the soil (or lowering pH) appears to
suppress the disease. If the soil pH is above 7, lower it using elemental
sulfur. Fertilize in fall with ammonium sulfate. Also, irrigate based on
evapotranspiration needs of turfgrasses.
Treatment Decisions
Fungicides may be necessary on golf greens that have experienced the disease in
the past. Apply a fungicide on a preventive basis in fall.
| Common name |
Chemical class |
Many of these products are available for use by licensed applicators only and cannot be used by home gardeners.
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| A. |
AZOXYSTROBIN |
QoI (strobilurins) |
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| B. |
FENARIMOL |
DMI |
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| C. |
MYCLOBUTANIL |
DMI |
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| D. |
PROPICONAZOLE |
DMI |
UC IPM Pest Management Guidelines: Turfgrass
UC ANR Publication 3365-T
Diseases
F. Wong, Plant Pathology, UC Riverside
M. A. Harivandi, UC Cooperative Extension, Alameda Co.
J. Hartin, UC Cooperative Extension, San Bernardino Co.
Acknowledgment for contributions to the disease section:
M. E. Grebus, Plant Pathology, UC Davis
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