posted 7 years ago
Yes, the little one in the upper right hand corner of the top picture looks just like the dock or rumex that grows here. But maybe a lot of things do, and San Diego is a very different climate than any that I've ever lived in, so I wouldn't know. Docks tend to be edible, but some are too high in oxalic acid so they are no so good to eat. Check if there's a native plant website for your region.
Regardless of what it is, if it were mine and I wanted to get rid of it, I'd try two different tactics.
If it is a space that you can leave unused for a while, it might be helpful to lay down several layers of plain cardboard or paper, with a pile of woodchips or similar on top, and water it from time to time. If the pile of woodchips is deep enough, you don't even need the layer of cardboard or paper, but you just want to be sure those plants can't shoot up through the mulch. After a few months, the plants would lose strength, and the soil would get soft, so you could dig it out getting most or all of the root. And you'd have lovely soil, then, too.
If it's too close too other stuff or you can't spare the area for a pile for months, then consider chopping it frequently and using it for mulch around other plants, never letting it go to seed. It would lose strength, though the taproot might remain firmly in the ground, so it wouldn't be a final solution. In this case you could consider it a "dynamic accumulator" whose taproot is bringing up nutrients from the deep soil and allowing you to provide the nutrients to other plants as mulch.
I planted French sorrel (a Rumex) last year, after reading how it is so hardy, and the earliest green, and a nice sour lemony taste, etc etc. Turns out I really don't like it, and now I want to get rid of it. So I'll be doing one of those tactics myself, too!
Works at a residential alternative high school in the Himalayas SECMOL.org . "Back home" is Cape Cod, E Coast USA.