Golfdom, March 2018

OIL FUEL DAMAGE Hydrocarbon machine fluid injury on greens What do we know By Lee Berndt Ph D M otorized turfgrass management equipment uses hydrocarbon based machine fluids including fuels lubricants and hydraulic oils Leaks of these machine fluids injure turf especially on greens Photo 1 The most pronounced visual symptom of machine fluid injury is an area of turf exhibiting loss of visual green color with the onset of shoot necrosis Over the last 35 years only a handful of research reports have addressed machine f luid injury Gaining a better understanding of this injury type through additional research may lead to enhanced spill mitigation tactics This could be important for golf course superintendents as spills of machine f luids occur frequently on greens all over the world This article summarizes our current understanding of machinefluid injury on putting green turf MACHINE FLUIDS ARE CONTACT PHYTOTOXINS Its not yet clear why machine fluids are phytotoxic A literature review suggests petroleum hydrocarbons i e gasoline are lipid solvents which upon contact with grass shoots causes dissolution of cell membranes Rupturing of cell membranes causes cell constituents to leak out resulting in cell death Alternatively other petroleum hydrocarbons i e oil may physically obstruct stomata interfering with gas exchange and transpiration Hydrocarbons infiltrating the root zone may cause anaerobic or hydrophobic root zone conditions that interfere with essential functions such as root respiration and the uptake of water nutrients SPILLS AFFECT SHOOTS AND ROOTS Its obvious that machine fluid spills affect turfgrass shoots as canopy injury is visually observable Whats not so obvious is that roots are affected as spills of hydrocarbons infiltrate soil This was demonstrated in 2017 when fluorescent dye was added to vegetable hydraulic oil The oil containing the dye which fluoresces under UV light was heated to 176 degrees F and 01 fl oz was applied to the center of a 4 inch diameter plug of TifEagle hybrid bermudagrass Cynodon dactylon X C transvaalensis Photo 2 Shining a UV light on the turf canopy left clearly showed shoots were covered with oil as the dye f luoresced wherever oil had spread Cutting the plug in half revealed that some of the oil had infiltrated to a depth of about 1 inch affecting not only roots but root zone micro organisms as well Research to determine the spatial distribution of machine fluid spills begins this year MACHINE FLUID INJURY BEHAVIOR IS DYNAMIC The term dynamic refers to changes in a pattern or process with time Injury resulting from spills of six different machine fluids including brake fluid diesel fuel gasoline motor oil petroleum hydraulic oil and vegetable hydraulic oil were similar in some 36 Golfdom March 2018 Golfdom com ALL FIGURES AND PHOTOGRAPHS BY LEE BERNDT PH D Super Science PHOTO 1 The aftermath of a hydraulic oil spill on a TifEagle hybrid bermudagrass putting green in southwest Florida