The presence of red or pink webbing or thread is the tell tale sign of red thread. Red thread is a turfgrass disease most likely brought on by low levels of nitrogen in the soil. When I begin to see red thread, it tells me it's time to fertilize.
- Low levels of nitrogen
- Temperatures between 68˚ and 75˚
- High humidity
Conditions favoring red thread:
Cool season grasses like red fescue, ryegrass, Kentucky bluegrass, and bentgrass are most susceptible. Some varieties have red thread resistant qualities including: 'Bilart' and 'Claudia' fine fescues; 'Chateau' Kentucky bluegrass; and 'Pennant' perennial ryegrass.
Red thread can be treated with chemical fungicides, but the best way to deal with it is to fertilize with adequate nitrogen, maintain a pH level of 6.5 - 7.0 and water deeply in the early morning.