Caring for your lawn includes removing thatch when it is built up. Thatching blade on Amazon USA: http://amzn.to/2rrwZQt
Canada: http://amzn.to/2vBzvcL
UK: http://amzn.to/2xGiT1b
(affiliate links)

Using a lawn mower to remove thatch from the grass just requires putting on a special blade and being ready to clean up all the dead grass/roots that are pulled up. See how it was done in my yard. This should help your lawn be healthier.

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