Help me, I'm strapped!
Whenever I'm out in the yard, I'm looking for any needs my plants might have. From soil that is too dry to branches from a tree shading some smaller plants too much, I scan and look for ways I can help. This same eye for detail applies when I pull into a parking lot at a mall or other commercial establishment. It is at those places that I am horrified to see the atrocities committed against trees by unthinking landscape workers.
The thumbnail picture at right shows what happens when strapping used to brace a young, newly planted tree is left on way too long. This poor tree is practically being strangled. Furthermore, the strapping used is nearly impervious to degradation, being the same type used for attaching shade fabric to wood framed shade houses in commercial nurseries. While this tree is still surviving, the places where the strapping has cut in are going to be much weaker in storm situations, leading to possibly fatal damage to the tree.
All that was required in this situation was for the landscape contract to specify that strapping had to be removed from the trees once they had become established. If the landscaper wished to avoid the return trip, a type of biodegradable bracing could have been used instead so that as the tree grew, the strapping would deteriorate and fall off before causing the girdling damage. The landscape customer should insist that the landscaper take care of this, or that the tree be replaced if the landscaper was negligent regarding the contract. Sadly, most cases I've seen involve customers whose concerns don't include the welfare of their landscaping.
Other methods of bracing trees involve the use of metal or wire strapping and wood blocks, or bracing timbers with nails hammered directly into a tree trunk. Metal strapping must be removed promptly once a tree is established, and nails should never be hammered into a live growing tree. Some landscapers use wire and short sections of hose to protect the tree trunk from the wire, but I've also seen these left on so long that the hose was engulfed by the growing tree! The proper use of tree bracing aids can help a tree get a good start, but the landscaper needs to follow up with their work for this to happen.
All Knotted Up
Abuse of landscape plants doesn't happen only at or after installation, either. Often hidden problems that started in the nursery show up much later in the landscape situation. The most common is girdling roots caused by growing a plant too long in a standard nursery pot. Field-grown landscape trees begin their lives in nursery pots. If small trees are kept in these pots too long, the roots will circle and harden (see picture at left). Roots don't unfurl underground like tentacles; they stay in that same circled condition and can eventually choke the tree to death. Also, a tree with such a deformed root system is much more likely to fall over in a storm. This problem is hard to spot in trees coming in for installation unless the trees are coming out of pots. If you are involved in a landscape job, you should inspect the root balls of any trees or shrubs being installed and reject any that show this damaging root circling. The landscape and nursery industries will be responsive to their customers, but only if those customers speak up and insist on plants and trees that have been cared for properly. Some nurseries are already growing their woody nursery stock in root pruning containers instead of standard nursery pots. Such plants and trees establish in the landscape more quickly and make for superior quality field-grown material as well.
For more on circling roots, see my other article, Do the roots in your pots go round and round?.
Image credit: Delia Garner