Bipolaris

What causes Bipolaris?

Bipolaris is caused by the fungi Bipolaris spp. and is most commonly a fungal disease of turf growing in stressful conditions with a poorly draining surface.

When does Bipolaris Occur?

In general, the conditions favouring Biplaris are:

• Cool, wet periods from autumn to spring where foliar blight and lesions occur

• Warm humid weather throughout summer where crown and root rot may occur

• More than 10 hours a day of leaf wetness for several consecutive days.

• Poor air movement (high humidity in the micro-climate).

• Excessive nitrogen fertiliser.

• Excessive thatch and loose leaf clippings provide a source of food for the fungus.

• Any stress situation such as drought, herbicide injury or heavy traffic can increase the severity of the disease.

What Turfgrasses are Especially Susceptible to Bipolaris? 

Warm season turfgrasses

What can I do to manage Bipolaris?

Management practices that can help manage or reduce instances of Bipolaris include:

• Maintain healthy turf through proper fertilisation. In particular, paying particular attention to potassium and nitrogen levels.

• Irrigate infrequently and deeply. Avoid late afternoon or evening irrigations.

• Do not allow the turf to become extremely dry during warm weather.

• Increase air movement and improve drainage

• Avoid herbicide applications during critical periods of disease activity.

• Disperse traffic in high-traffic areas.

• Mow turf at a height recommended for the turfgrass species.

For chemical solutions and treatments for Bipolaris, please see the recommended products below.