I planted a Japanese maple in the summer of 2006, and supported it with 3 stakes. The tree is now about 7 feet tall, with a slender trunk only about 1 inch thick. How do I know when it’s ok to remove the stakes?
The staking is more for the roots grow out enough for the tree to be stable in winds. It won’t hurt to stake it longer. Be sure to adjust the support stakes occasionally to allow for trunk growth. Under good conditions a tree the size you gave could have a good root system already. Only you can tell how it’s doing for sure, but a couple more years of support are likely needed. Even large established trees can tip in high winds, so you’re never 100% guaranteed a tree will stay straight.
I generally remove the stakes in one year, if the tree seems to be well-established in the ground. We have clay soil, so the usually isn’t a problem. Sandy soil might take longer.
A tree should be able to support itself after no more than one year, but one inch diameter for a seven foot tree seems kind of thin. It’s probably the stakes that are keeping the trunk so thin, because it doesn’t have to support itself in winds.
You should restake the tree with two stakes, aligned perpendicular to the prevailing winds. So if the winds blow from the West, have the stakes North and South. Don’t have the rope pulling taught on the tree. You want the tree to feel the wind, so it can strengthen its trunk. The stakes should only give it some extra support in strong winds. After another year, remove the stakes completely.
Scratch that. I was visualizing a tree much taller than seven feet. Just remove the stakes. Your tree should be fine.
Just be sure to check on the ties now and again to be sure they aren’t digging into the bark. A think tree like that will not need wire, but just twine, or if you think it’s not obtrusive then plastic garden tape is better, because it will stretch in a storm instead of cutting in.