One of the most important principles in landscape design is right plant, right place. This means that the designer (or whoever is selecting plants) chooses a plant that fits the light, soil, and size of the place it is intended. But here is another consideration. Don't put a plant with razor sharp thorns along a public stair railing.
This is one of my favorite plants: Berberis or commonly called barberry. It's a great shrub, sometimes deciduous, sometimes evergreen. I suspect this is Berberis darwinii, the evergreen cultivar. It has tiny flowers that pop against the foliage in the spring and tiny red berries in the fall that persist into the winter. Berberis has some of sharpest thorns in the plant world and at 1 1/2-2" long, could easily impale a person or animal. This is a great shrub for a hedgerow, since the thorns enable it to function like a fence, but it creates a great refuge for birds to safely nest.However, it isn't a good idea along a high school stairway, growing through the railing and trailing over the handrail. Sometimes, things just scream out, "What were they thinking?" Most likely, they weren't.
