Brown patch of Pyracantha spp

Disease Information

Brown patch

 Rhizochtonia solani

Symptoms

Brown patch is a common patch disease that affects several cool-season grasses  .primarily tall fescue. Symptoms can appear quickly in warm, humid weather, primarily when nighttime temperatures

exceed 70 F during heavy dew formation.

During favorable conditions, fungal resting spores in the thatch begin to grow and rapidly damage the susceptible turf. Symptoms may appear as circular brown patches ranging from inches to several feet in diameter or as large blighted areas that lack a distinct pattern. The circular patches often are bordered by a brown band referred to as a smoke ring. Irregular,

tan lesions with a brown border usually are visible on individual grass leaves. Mycelium often are visible between grass blades in infected areas in the morning, especially in the presence of dew.

COMMENTS on disease

 Brown patch rarely kills the turfgrass crown, which allows the turf to recover after favorable disease development conditions subside.

In addition to favorable weather conditions, brown patch development can be promoted by improper cultural practices such as over fertilization, excessive leaf wetness caused by watering lawns during the early evening hours and by allowing thatch to accumulate.

 

Chemical control

 Heritage (azoxystrobin), Compass (trifloxystrobin), Bayleton (triadimefon) and Prostar (flutolanyl).

 

Cultural methods

 Do not over apply nitrogen fertilizer, avoid prolonged leaf wetness

by providing irrigation deeply and infrequently in the morning or early afternoon, and prevent thatch buildup.



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