Those “weeds” cropping up in cracks in the sidewalk? It turns out they’re edible—and expensive to buy in bulk. We spent an afternoon with Firefly Executive Chef Todd Wiss who says skip the store because there’s food to be found, even in a city. We plucked figs, plantain, wood sorrel, dandelion greens, purslane, and yarrow during a short walk in Dupont. “If you know what you’re looking for you can feed yourself,” Todd tells us. But there are rules. “Wash things five times and if you can’t identify it, don’t eat it!”

A demanding kitchen means Todd can’t always be in the field, so his Sous Chef Shane Graybeal hired professional Silver Spring based forager, Matthew Cohen. On Wednesday they found persimmons, wild grapes, burr cucumbers, rose hips, and burdock. It’s all in preparation for a foraging dinner at Firefly on Oct.  22. The menu includes three mushroom risotto with uni butter, crispy pork belly, and a sassafras ice cream sandwich. Call to reserve a seat. The $75 dinner is capped at 16 people.