1.Thefallenleavesonthegrounddecomposeandserveasnutrientstonourishthebigtree.2.Whenleavesfalltotheearth,theyrotandprovidefertilizationforthelargetree.3.Leavesthatfallanddecayonthegroundactasfertilizertofeedthebigtree.4.Asleaveslierottingontheground,theycontributetothenourishmentofthelargetree.