Question
I have Swedish Aspens that I planted in the summer of 2009.  Now they are 9+ ft tall.  I staked them.  How long do I need to keep them staked?  Also I have 7 ft crabapple trees that are staked. How long do I need to keep them staked?

Answer
Most trees will not need to be staked longer than a year, but should be left for at least one growing season.  As soon as the tree can stand on its own, remove the stakes.

Though, most newly planted trees will grow better if they are not staked.  By leaving the young tree to move freely in the wind, it will develop a better root system and a stronger, more tapered trunk.

Just as we exercise to stay healthy, trees need to move to be healthy. How does a tree move? In the wind, of course, and wind is the very thing that stakes are supposed to protect trees against. When a staked tree does sway in the wind, buds that might have become branches are rubbed away, and developing bark bumps and scrapes against the stake causing wounds. Insects are attracted those open wounds.