Over the past three weeks, I have devoted hours to uprooting this villain.
Name: Japanese knotweed a/k/a elephant ear bamboo a/k/a Mexican bamboo a/k/a fleeceflower a/k/a Polygonum cuspidatum
Identifying marks: bamboo-like hollow stems, reddish new growth, succulant white rhizomes with orange exterior
MO: spreads by underground roots . . . and spreads . . . and spreads
This invasive grows so quickly that it suppresses native species. Its science-fiction monster roots can run 12 feet deep and 20 feet distant from the stalks. Just a half-inch length of rhizome can sprout.
According to this very helpful publication by UC-Davis, control requires constant vigilance. The best eradication results from a combination of digging out the plant roots and applying herbicides. I'm committed to the first option and will be waging a war of attrition--apparently for the next several years.
A close-up of the battlefield: the muddy patch next to the neighbors' new fence. It's on its way to becoming part of a raingarden.
I have grubbed out roots, moved building rubble, added 7.2 cubic feet of peat moss, dug in several buckets of compost, and planted this lonely little forsythia Lynwood Gold. It will be joined in a few weeks by a plethora of clethra.
And, on an all together happier subject, the sunny beds along the back of the house are tearing along. The peonies have buds . . . and the buds have ants. Yay!