Disease symptoms are often found on Kentucky bluegrass during the summer and fine fescue in the autumn. On perennial ryegrass however red thread can appear almost anytime during the year. Red thread appears as circular to irregular shaped patches that are straw to pinkish in color. The patches appear as a brownish to tan in color, and overall give the turf a rather "ragged look". Under wet or humid conditions the patches may appear a pinkish red color with red strands (sclerotia) exuding from the leaf blade. In addition, pink cottony balls (small in diameter) may be present, especially on perennial ryegrass.
Authors: Karl Danneberger
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