Hollow Tine Aeration. Hollowtine aeration is essential for a beautiful lawn. We recommend you have the lawn aerated at lease once every 2 years. Your lawn is continually being compacted regardless of how often you walk on it. Eventually the weather, and the mowing will inhibit root development. Compaction is the main reason for moss in the winter and main reason for  dry patches during the summer. We only use the best hollow tine machines available. There may be a need to top dress the lawn for leveling reasons if you feel this is needed we would be happy to advise.