https://www.cbc.ca/news/technology/don-t-rake-leaves-ncc-1.4887187 Justiication for not removing leaves.
http://durgan.org/2011/November%202011/7%20November%202011%20Mulching%20Leaves%20with%20Lawnmower/HTML/ 7 November 2011 Mulching leaves with Lawnmower.
All the leaves on my property are mulched with the lawnmower and left where they fall. The lawnmower grass exit port is held closed with a self tapping screw. The pile of leaves are run over by slightly lifting the front of the lawnmower, and the leaves are instantly chopped into small pieces. They are left where they fall for fertilizer. It is not necessary to put the leaves in a pile, but it simplifies matters by doing so.