English

Noun

yellow patch ‎(plural yellow patches)

1. (historical) A yellow badge.
2. (mycology, pathology) A disease affecting several varieties of grasses, including bentgrasses, annual bluegrass, some perennial ryegrass and Kentucky bluegrass, which results in the development of yellow or brown rings.
   • 2002, Peter H. Dernoeden, Creeping Bentgrass Management: Summer Stresses, Weeds and Selected Maladies, Hoboken, New Jersey: John Wiley & Sons, Inc., ISBN 157504143X, page 25:

     Throughout the year pathologists receive numerous samples of yellow, creeping bentgrass or annual bluegrass (Poa annua) from putting greens. In autumn or spring, superintendents sometimes suspect that yellow tuft (Sclerophthora macrospora) or yellow patch (Rhizoctonia cerealis) diseases are the problem.

   • 2013, Thomas L. Watschke, ‎Peter H. Dernoeden, & ‎David J. Shetlar, Managing Turfgrass Pests, ISBN 1466555076, page 97:

     Yellow patch, sometimes called cool-temperature brown patch, develops during prolonged cool (50-65°F; 10-18°C), overcast, and moist periods from late autumn to early spring.