Description

Red Thread can occur any time during the growing season, but it is more prevalent during cool, humid, spring and fall days when the air temperatures are between 16°C and 24°C (60°F and 75°F). The disease is especially severe on slow-growing nitrogen-deficient turf.
Characterized by the red and coral pink, thread-like structures of the fungus, which protrude from the tip of the grass leaves (at right angles). Usually, the affected areas produce 4-to 5-in. diameter spots

Favorable Conditions

Low nitrogen, high humidity, cool, wet weather and slow growing turfgrass.

Susceptible Grasses

It can be a problem on Annual Bluegrass, Kentucky Bluegrass, Bentgrass & Ryegrass. Fine-leaved fescues and some ryegrasses are particularly susceptible.

Management Recommendations

Get the lawn growing again, producing new leaves by applying a light application of fertilzer. The fertilizer can help mask the symptoms and boost turfgrass recovery. Ensure good soil fertility thru the balanced application of fertilizers throughout the growing season.

Do not allow thatch levels to accumulate. Aerate annually.

Ensure a soil pH of 6.5 to 7. Apply lime if the soil is acidic.

Avoid overwatering. Do not water the lawn in the late afternoon or evening. Provide good soil drainage. Plant trees and shrubs far enough apart so that large areas of grass do not remain shaded for long periods during the day and so that dew and other moisture on the grass will readily evaporate. Selective pruning of established trees and shrubs may also help.

Overseed with new cultivars of turfgrass that are resistant to the disease. Use resistant varieties of Kentucky bluegrass (Ascot, Classic, Dawn, Eclipse, Princeton, Trenton), perennial ryegrass (Lowgrow, Lynx, Navajo, Passport, Precision, Rivierra II, Shining Star, Target), and fine fescue (Biljart, Bighorn, Reliant, SR 3000, Waldina).