Most lawn-care operators realize that a dull mower blade will shred grass blades, leaving a tattered appearance. If that's not bad enough, dull blades have also been shown to increase disease incidence in some circumstances.

Another supposed drawback to dull mower blades is that tattered grass blades promote greater water use, presumable through increased evaporation through the exposed tissue.

However, University of Nebraska researchers found that turfs mowed with a sharp mower blade used 33 percent MORE water than those mowed with the dull mower. This may have been due to the slower growth that occurred with dull blade damaged. Not that this makes a good argument for mowing with dull blades, considering the remaining drawbacks.

The Nebraska researchers found another interesting result during this study: Mower fuel consumption was 22 percent less with a sharp blade than with the dull one. In these times of high fuel prices, that alone should be incentive to keep your blades sharp.