It doesn't get more local than this.

I am kneeling in moist soil next to six rows of baby lettuce mix — an earthbound salad of reddish oval leaves interspersed with broad and branchy green ones — at a Roxborough farm four miles from my house.

We joined a community supported agriculture network (CSA) this year, which means my partner and I ponied up a few hundred dollars at the start of the growing season — enabling the farmers to buy seeds and fertilizer and pay the water bills — in exchange for a weekly share of the harvest from late May to October.

So far, it's been heavy on the greens: collards and two different types of kale, pak choi and bok choi, chard and radish tops (delicious, even if they look like you mowed the lawn and then cooked the clippings).

We liked the idea of eating organic veggies in season. In fact, we were so delighted by the whole concept of "Henry Got Crops" — a partnership of Weavers Way Co-op, Weavers Way Community Programs, Saul High School and Fairmount Park — that we decided to go one step further: We'd get a discount on our CSA if we each agreed to put in four hours of work on the farm this summer.

And so I showed up at the appointed hour a couple of weeks ago, wearing plastic clogs and a visored cap, and looked around for the Farmer in Charge.

Old MacDonald, this is not

When I picture a farmer, I visualize someone from a children's book: coveralls, hands wizened from hard work, an odor of earth and onions. But the first farmer I meet this morning is a man in a plaid kilt and battered work boots, a gold earring in his left ear and a verse from Psalm 40 printed on his t-shirt. The other farmer — my supervisor for the morning — is Emma, who wears her hay-colored hair in a thick braid and pockets a serrated bagel knife as a harvesting tool.

This morning, she explains, I'll use that knife to give the salad greens a haircut. But first, I must ruffle the rows, looking for any shoots that have begun to bolt. Bolted stems, even those just starting to bud, are tough, not tasty. Not what people want in their salad mix, especially at nearly $12 per pound.

At first, this is fun — a challenge, even: Can I rid the mix of anything that might be a bitter bite for the consumer? But after 10 minutes, the sun is a hot stone on my back, tiny bugs are nipping my forearms, and my quads are numb from squatting.

By afternoon, this salad mix will be neatly, moistly bagged and shelved at the Weavers Way store in Chestnut Hill. I think of how many times I've grabbed greens from that shelf, never once thinking about how they got from the ground to my cart, or whose knees and back must be screaming from the labor.

Once I've shorn the six long rows, Emma carries the box uphill to the washing station, where she dumps the greens into a giant sink. A cool-water dip sounds pretty good to me, too, right now. But a farmer's work (even a volunteer farmer's) is never done, so we trudge back downhill.

And here is a new challenge. A weed called galinsoga lurks amidst the lobes of arugula, and I must pluck it out before the arugula goes anywhere. Galinsoga (sometimes called "gallant soldiers," though Emma tells me one volunteer insists on calling it "gorgonzola") has a hairy stem and pointed leaves that branch from both sides. The arugula leaves are oval or palmate, and their stems are smooth.

Green thumbs don't run in the family

Uh-huh. At first, it all looks green and leafy. I'm a kid of the city and suburbs, after all, raised with a backyard swing set and an occasional Big Boy tomato plant. My ancestors — Jews from Eastern Europe — are people of the book, not the back 40. Even cacti used to expire on our windowsills.

I was taught that nature was an attractive backdrop, something to be given an appreciative nod ("Oooh, look at that sunset ... now, did you see the piece in the Times Book Review?") but not demanding interaction or engagement. In my family, we didn't talk to plants. We didn't even know their names.

And though my mother was prescient about the dangers in certain processed foods — no cereals with Red Dye No. 2, no hot dogs with nitrates — we ate without regard to season or locale: raspberries in February and tomatoes in December. We never considered the price, to ourselves or to the planet, of those heedless hungers.

When I grew up and wanted a garden, I had to learn from scratch. After 25 years of planting in back yards from Portland, Oregon to Philadelphia, I'm still an amateur, trying and failing and trying again. What is chewing my basil leaves to lace? Why did I get a bounty of cherry tomatoes last year, while this year the plants never blossomed? And how come butternut squash is sprawling all over the yard, when we never even planted it?

Sometimes, the land — even my own modest garden — feels like foreign territory, the language of seeds a code I never learned to crack.

The ground and I, no longer strangers

But here's what happens as I crouch in the arugula. I start to forget where I am. The cars on Henry Avenue river by in a whoosh of white noise. The birds are making chirpy conversation; the arugula smells greenly fresh. And then, after a while, I forget who I am: the girl who can harvest only words, the girl with ink-black thumbs.

I find a crouching position that doesn't make my quads ache. I get better at spotting the hairy, gallant soldiers and plucking them out of formation. I lop off the arugula leaves, just as Emma instructed, and the heap in my bin starts to look like something I would want to eat.

I finish the row. We schlep the greens uphill and swirl them in their cool bath. A touch of OCD comes in handy as we pick through the water for wilted leaves, an occasional snip of stem, a bit of galinsoga that escaped my notice in the field. Finally, we use giant sieves to scoop arugula from the sink and shimmy it dry. It will be whirled even drier in salad-spinners, then bagged and driven to the store.

By tonight, it may be on my plate. Or yours. And when you taste that peppery forkful, dressed with just a lick of olive oil and lemon, think of the farmer, with her sun-warmed shoulders and her serrated knife, think of the knowledge that eating globally has allowed us to forget: every bite, whether we acknowledge it or not, binds us to some inch of earth.