The document discusses the importance of proper calibration and maintenance of mechanized equipment used for lawn care. It provides steps for calibrating both granular and liquid spreaders to ensure accurate application rates. Key steps include determining the machine speed and spread width, doing calculations to find the proper application rate, verifying the speed and pattern width, and doing test runs to adjust the rate dial as needed. Frequent calibration and cleaning of equipment components like nozzles, impellers and hoppers is emphasized to avoid issues like inaccurate applications, turf damage or chemical burns.