Saturday, September 22, 2007

Crabgrass in my Garden

I love volunteers in the garden, those mystery plants that sprig up and only gradually reveal their character. I’ve got a magnificent mullein that was a volunteer—it always makes visitors gasp—and it’s now the matriarch of a thriving colony of mulleins, most of which I will root out (mainly because they take up so much room).

The woman who gardened in my plot before me planted a plant with red-trumpet-like flowers to attract humming birds. It is more invasive than mint or bamboo. It can't be killed, it sneaks around barriers of metal, and no matter how many times I ruthlessly rip it out, I never win the battle. We are in a struggle.

The newest volunteer in my garden is also in this unwelcome category. In the spring, I noticed a grass that was poking through the branches of my big lavender plant. It gradually spread through my garden in waves, slyly insinuating itself all through the herb and iris bed, then creeping around the back and entering the bed with the dog roses, strawberries, arugula and basil (it hasn’t reached the back bed yet whichis where I am doing battle with the red trumpet flower plant). This plant spreads underground, the white roots creeping through the earth before poking up green shoots in some new location. When I try to rip it up, I sometimes yank out the root, back to its last outpost, but I never seem to be able to track it back to its source. Trying to disentangle it from my small lavender bush, I had to dig up the plant, so inexorably were their roots entwined, and, as a result, the lavender died.

The mystery volunteer is a grass so I finally decided to make it the latest subject in my grass identification project. I plucked a fine mature specimen: tall stem, gay green ribbons of leaves and a seedhead with four horizontal grainy blades like a little heliocopter. Can you guess what it was?

Yes, crabgrass. Unremarkable, insidious, unloved, unquenchable crabgrass. When I googled crabgrass to learn about its name, the suggested combinations were “crabgrass control,” “crabgrass removal,” “crabgrass prevention,” “crabgrass herbicide,” “crabgrass treatment,” “crabgrass prevention,” and “crabgrass kill.” It seems no one wants it around.

My new favorite Northwest plant identification guide (known affectionately as Pojar’s) says that it is digitaria sanguinalis (an interesting name suggesting it has something to do with fingers and blood but I haven’t found an explanation for this name). The explanation for its common name, crabgrass, is that it creeps sideways like a crab, or the nodes look like crabs. The little whirligig at the top of the plant is the inflorescence—it flowers from August to September in our area.

The Plants for the Future website says that the seeds can be ground up into flour and the leaves used to make paper. So nice to know there is a positive use for this plant. I was curious to know how to make paper from grass so I did a little snooping around the internet. Apparently it can be quite a difficult process, involving caustic chemicals. The instructions from Akua at the Art Farm, seemed the simplest.

Pojar, Jim and Andy MacKinnon, Revised Plants of the Pacific Northwest Coast, B C Ministry of Fores and Lone Pine Publishing, 2004


wil said...

I wonder if sanguinalis relates to the cheerful, confident, hearty meaning(s) of sanguine, being that it's such a hearty/confident weed.

wil said...

A google book search turned up this:

Its scientific name, Digitaria sanguinalis, refers to the reddish color of the fingerlike branches of its flowering panicle (hence it is sometimes called finger-grass), but farmer and biologist Edwin Spencer, writing for a popular audience, added, "If sanguine means ardent and filled with enthusiasm, that name fits this plant perfectly," and he called it a "weed of nine lives."

- The Culture of Wilderness: Agriculture As Colonization in the American West by Frieda Knobloch

Waverly Fitzgerald said...

Thanks for finding that reference for me. Both explanations make total sense.