I used to stake new trees real tight, figuring it kept them straight. After a few seasons, I saw trees with girdled trunks and weak roots. Last year, I planted a red oak and tied it down hard. By summer, the bark was cut into and the tree started to lean. An old timer showed me how loose ties let the tree sway a bit. That movement helps the trunk grow strong and roots dig deep. Now I use wide straps with plenty of slack. If you stake trees, give them room to move or you might hurt them for good.
That part about the old timer showing you loose ties really hits home. Tight staking doesn't just hurt the trunk, it can make the tree more likely to get sick. When the bark gets cut, bugs and fungi can get in easier. Honestly, I saw this with a maple I planted too tight, and it got infested with borers after the straps dug in. Letting it move a bit might actually help it fight off pests on its own.
Wow, I always figured tighter stakes meant better support for young trees. Your story about the maple and borers completely shifted my view on that. It's crazy how something meant to help can actually weaken the tree and invite trouble. Letting it sway a little probably does build its own defenses like you said. How do you know when the ties are loose enough without the tree falling over?