I’ve been kind of assuming that weed that’s been steadily marching across our yard was clover, even though it had a different leaf edge (frilly vs. smooth), root structure (dense with runners vs. fibrous) and flower (yellow petals vs white/pink/red balls). A very short search on the web turned up this website, which made it clear that we are dealing not with clover, but with buttercups. Hmmm.
A little bit more searching, and I’m increasingly impressed at the scale of the problem. Apparently buttercups, with their runners and thick roots that can grow up to 25 cm deep are a nearly unstoppable force. They thrive in damp and acidic soil. (Check and check.) They crowd out all other life forms. And, to top it off, they’re poisonous and you can get bad rashes if you come in contact with them or breathe the leaves’ oil. Super.
It sounds like we have two options:
The first is to give up on the grass and go for a buttercup yard. The advantages: at this rate of growth, the yard will be all buttercup by the end of the summer, the leaves are genuinely attractive and tolerate mowing well, and buttercups appear to be the only thing that can out-compete the moss. Disadvantages: we’d miss the grass, and some sort of containment is needed to keep the buttercups from marching straight into the garden beds (which they’re also taking over).
The second option is to just start spraying immediately with highly potent broadleaf killers, and to repeat frequently until the last of the stuff is dead. (And then to stay on guard because that root structure is dense, deep, and long-lived.) Advantages: cheap, relatively easy, not too time-intensive, more-or-less effective over time. Plus, Kevin gets to use the chemical sprayer, which makes him cheerful. Disadvantages: toxic chemicals.
The third option is to try to dig it out manually, but we’d have to dig a foot down and replace all of the topsoil to be guaranteed success, and the time investment, difficulty, and expense effectively renders this a non-option.
Sounds like we have weed poison in our future?