Have you ever noticed, while mowing that some of the grass is randomly left sticking up?
Your first thought is usually that the mower blades need sharpening. While you have the blades off, examine the back edge of the blade. If this portion of the blade shows considerable wear and tear, then the blade needs to be replaced. This is the portion of the blade that gives lift and vacuum to the mower so that the blade is able to cut the grass more evenly. On a double-bladed mower, this wear pattern will cause a narrow strip of grass to be left between the blades.
By paying attention to this technique, you will have a more evenly mowed lawn.
Gary Dobbs, Smith County Master Gardener
Texas AgriLife Extension Service
Landscape Index
Gardening Tips For NorthEast Texas Index
East Texas Piney Woods Gardening Home Page