If you’ve wondered about some of the landscaping features at Park Van Ness…

If you have seen these black rectangular additions to the Park Van Ness landscaping and wondered what purpose they serve, you’re not the only one.

David Bardin writes:

I wondered what all those black things were for. Could Park Van Ness be planning to install something on top of them? For a day or two I wondered.

Then, walking down to MetroRail on Tuesday, I saw a man working there and asked. He said that skateboarders zinging along the edge were marring the granite surface. The black plastic things were designed to deter them. And they work.

The granite is discolored along the edge due to skateboards scraping against the surface.

“Yankee ingenuity,” I thought, akin to spikes on window sills outside public buildings, designed to deter pigeons. “What are they called?” I asked. He told me, and pointed to a box in which they came.