Small Engines (Lawn Mowers, etc.): Lawn Mower, dull blade, low clearance

Question
Sir: can you explain why a lawn mower would eat up a patch of the lawn leaving  ball spots ? Could it be because I set the mower too low clearance or the blade is dull? Be advise.

Pete

Answer
Too low of mower clearance is the main cause for leaving "ball" spots.  A dull blade usually results from this situation an the blade is contacting the ground.

A dull blade will cause poor cutting performance but will not cause "ball spots".

Eric