We “straighten up” quite a few trees every year for various reasons. Due to high winds, heavy rains, and wet soil, trees can start to lean. Although a leaning tree doesn’t necessarily mean it is unhealthy, it can look strange in a well-maintained suburban setting, depending on its root condition. This Learning Spruce Tree was a great example of straightening tipping trees.
This tree was the largest of all leaning trees that Heartwood had straightened in 2016. This tree was between 25-30 feet tall and was tipping/leaning quite a bit. This tree was too shallow-rooted to withstand the wet spring weather (which destabilizes roots systems and loosens soil), and strong winds later in the year (which pulls on roots and levers them strongly)
A leaning tree can sometimes be saved, depending on its severity and condition. Sometimes, if the tree is severely leaning or its roots are exposed, it is impossible to keep it. We could save the tree because this customer was interested in protecting it. The tree is still alive, as far as we know!
As you can see from the second photo, uprighting is easy. One rope was rigged through a pulley and attached to the spruce. The other end was attached to the poplar. This created a 5 to 1 mechanical advantage system. The 5-to-1 is the shorter yellow rope that hangs above the drooping orange one. This mechanical advantage allows for superhuman strength to pull the tree straight up, increasing the person’s force pulling on the line by roughly five times. However, we lose some energy due to friction between the ropes and pulleys.
To hold the tree in its place, we attach three poly cables (ropes). Two lines were attached to posts pounded into the ground to provide stability. The second cable was connected to a poplar trunk that supports the spruce.
Leaning trees pose a significant concern because the roots must be strong and healthy enough to try to straighten them. The origins were buried and still intact in this instance. The next issue is where to tie the tree. I was able to rely on the strength of this tree in this instance. We might have considered other options to support the tree with three metal posts.
For trees this large, it is best to leave the cables in place for at least a few years once the tree has straightened. Every tree is different, so it is impossible to predict how long they need support. The cables can be adjusted to maintain proper tension over time. You can check the pressure by letting the line loosen a little and see what happens. If the tree doesn’t move when the cables are released, it might have enough root system to stand independently. It would be nice if there was a better way to do this, but it isn’t.
While we had many successes last year in repairing many “ships,” there were also some mistakes. We are willing to straighten any tree if the owner is interested. This is because tree straightening can be dangerous, but it’s worth a try if you have the time.