Why this simple program cannot work? Please explain in detail

public class Tree{ int Leaves; int Feet; public Tree (int iniLeaves, int iniFeet){ this.Leaves = iniLeaves; this.Feet = iniFeet; } public void grow(){ this.Feet = this.Feet +5; this. Leaves = this.Leaves + 10000; } } public class Main{ public static void main(String [] args){ Tree byTree = new Tree(iniLeaves: 50000, iniFeet: 50); System.out.println(byTree.Feet); System.out.println(byTree.Leaves); byTree.grow(); System.out.println(byTree.Feet); System.out.println(byTree.Leaves); } }