In February of this year a utility cart tracked glyphosate up onto the slope shown in the photograph. The overseeded ryegrass died underneath those wheel tracks exposing the dormant bermudagrass. Meanwhile, the overseeded ryegrass, mown at approximately two inches over the winter and spring months, remained healthy outside of these tracks and competed with the underlying bermudagrass for water, nutrients and sunlight. So much so that where the ryegrass lingered on into the summer the underlying bermudgrass suffocated and ultimately resulted in bare ground. A lesson learned from this innocent mistake is to never underestimate the detrimental impact of the overseeded ryegrass on the underlying bermudagrass. With this in mind, it is great to see a continuing trend for golf courses in the deserth southwest to omit overseeding in roughs. Where overseeding continues, this lesson emphasizes the need for golf course superintendents to employ a proactive strategy to slowly and deliberately thin the ryegrass while improving sunlight penetration to the emerging bermudagrass.
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