Thermal convection on 419
View LargerPhotos provided by Charlie Goode (@GoodeTurf on Twitter), Turf Specialist - Vandemark Sod Farms. Photos taken on november 8th, 2020 at a Varndmark Sod farms. North Carolina, 419 bermuda mowed at 1.25 inches . The cause of the mottling is thermal convection where higher mowed turf funnels warm-soil-heated air up the plant as cold air flows down nearby resulting in distinct dormancy patterns that depend upon mowing height. Lower mowed turf enters dormancy more uniformly with foliage closer to the soil warm soil surface (mowing height effect). Here are similar symptoms on kikuyugrass and zoysiagrass.