As an environmentalist, fuck Kentucky bluegrass, fuck golf, and fuck lawns while we’re at it
I agree lawns are dumb but from an environmental perspective they can be net carbon sinks, which I found surprising. Though they are still bad for other environmental reasons.
Nothing can sink any more carbon than its weight plus any bits that fall or get taken and don’t rot. Worse, for most plants most of the weight is water, not carbon-containing organic compounds.
So lawns might be “net” carbon sinks only when compared to the extreme case of leaving the ground bare (or worse, asphalted), but only whilst they’re growing (they don’t really retain any additional carbon after grown and any grass mowned will just return the carbon back to the air when it rots and a lot of it will be Methane, a worse greehouse gas than CO2) and they’re a lot worse at it per unit of area than, say, trees or even just the natural ground cover in just about any land environment but desert.
Asphalt is definitely a carbon sink though since it’s a petroleum product!
I mean if you want to talk about sequestering carbon, there’s all sorts of natural lawn options that aren’t actively planting an invasive species that has proven to be really bad at doing any sort of water filtration or absorption. In fact, I’d wager that planting (and letting grow) prairie or whatever your native biome supports probably sequesters more carbon, assuming your native ecosystems aren’t straight up desert. Even if they are, you’re now using so much less water that it’s a huge net win there.