
Yesterday GM went over all the things you ought to be doing to help out our street trees. Today he’ll take up the slightly less pleasant task of going over all the things people do that they really ought not to.
#1 – Don’t Plant Anything in Tree Boxes Except Trees
Only one living thing should be planted in a tree box, and that’s a tree. This is a controversial point, since people love to plant everything from ivy to annuals to full blown bushes in their tree boxes. But these other plants take water and nutrients away from the tree, particularly young trees who are the most vulnerable.
And the problem can’t necessarily be obviated by simply watering more. In fact, that’s another problem with planting plants like annuals in a tree box. Annuals require a lot of water to survive, a lot more than a tree needs. When you water the annuals enough to keep them alive, you’re probably over-watering the tree.
Once you have a fully mature tree, it is probably less harmful to plant a few plants in the tree box. But really, a tree box is the most healthy when all that you see is thick healthy roots.
#2 – Don’t Use an Illegal Fence
District law has very specific requirements for tree box fences. They must be 18″ tall to prevent tripping. They must allow water to pass under them in order to increase the amount of rainwater being absorbed by the ground not the storm drain. Finally, they must be three sided and set back at least a foot from the edge of the curb.
While boxes like the one at the top of this post are pretty, they’re not permissible. The stones are too low and rainwater will just run around the box. Here are a couple other bad fences or borders on the exact same block: Continue reading →