Say what you will about the proposed tower parks, at least they won’t be built on land we could have actually done something with. For that kind of gross miscalculation, we return our attention to the Kennedy Greenway. Part of the sales pitch for the Big Dig was that it was supposed to rejoin the two halves of Boston that were severed by the Central Artery, and restore to the people the long, jagged scar of land it once covered. This, it was proclaimed, could best be accomplished not by reconnecting the cross streets and filling the space with good, mixed-use development—housing for various income levels, cafés, shops—but by converting it to a nebulous stretch of grass, overlaid at points with lattices of concrete and the occasional genocide memorial, the whole thing hemmed in on both sides by busy roads.

If urban development guru Jane Jacobs were still alive to see this, she would have bitten someone. In her book The Death and Life of Great American Cities—the sacred text for planners intent on overcoming the “urban renewal” that marred so many American cities—Jacobs stresses the need of cities to “foster lively and interesting streets.” Parks and squares should be part of the urban fabric, she argues, but “they should not be used to island off different uses from each other.” Even a quick glance at Jacobs’s book could have spared us this monstrosity. Just because you don’t have to walk under the Expressway anymore to get from Faneuil Hall to the North End doesn’t mean the two areas have been successfully knitted back together—in fact, in the name of mending the streetscape, planners have simply found a new way to keep it torn.

But the real folly of the Greenway is rooted in the popular notion that green space is inherently useful to people. It isn’t. We’ve taken nearly 30 newfound acres of prime urban land and converted it into something that will be used only in nice weather, during daylight hours, for at best seven months a year, and even then mostly by tourists. The rest of the time it will serve as the narrow, windswept, bum-strewn expanse that North Enders walk across to get to work in the morning, and then avoid after sundown. Sure, it’s an improvement over the rotting hulk of the old Artery, but it’s hard to look at the thing without thinking we could have done better.

As the North End and waterfront parks are unveiled this month, the pols and the papers continue their glorification of all things photosynthetic. But before the rest of us blindly follow them down this path, throwing fistfuls of sod at one another and handing big chunks of Boston back over to Mother Nature, let’s pause and consider two things: One, the best way to improve a city isn’t necessarily to make it less like a city. And two, this is Boston. Beyond the 5,500 acres of perfectly good green space we already have, we’re a half-hour from Lincoln. If your lust for grass is so insatiable that it can’t be slaked by a day at the Arboretum, or a stroll along the coves of the Esplanade (road or no road), go there. It’ll leave more space on the sidewalks for the rest of us.