We transplanted a number of larger (between 10 and 20 feet) Colorado Blue Spruces and Black Hills Spruces. We secured them with ground stakes and straps (3-4 each). The largest of them have been staked for 1.5 years (Fall, 2015); the smaller ones for one year (Spring, 2016). All were planted with a large tree spade with an earth cone about 6' wide and 6' deep.
Is it safe to remove the stakes and straps at this point?