Ms. Anzelone’s two sons, ages 9 and 11, who will join her along the ride today, will be dressed as species endangered in New York — one a Karner blue butterfly, and the other white milkweed.

The floral arrangement behind the bicycle includes a variety of plants native to New York City, which Ms. Anzelone showed us as she was building the contraption in Brooklyn this week. (It was filled with river birch, Jacob’s ladder, wild geranium, Solomon’s seal, wild columbine, spicebush, Mayapple, bloodroot, Virginia bluebells and a few other springy surprises.)

Behind the aromatic assortment is a large poster — a photograph that Ms. Anzelone took of a forest on Staten Island — to give people a sense of being in the woods, even amid the city’s otherwise concrete, skyscraping scenery. “The idea of traveling around,” she said, “is that people can take pictures of themselves in nature, even though they’re standing in Manhattan.”

When people think of nature in New York, she said, they often think of “Mannahatta: A Natural History of New York City,” a book that recreated, visually and scientifically, what New York looked like centuries ago when Henry Hudson first sailed the river that now bears his name.

“They think now it’s all gone, but it’s not,” Ms. Anzelone said. “There are so many pieces of the original Mannahatta that still exist in Manhattan, but most people don’t think about it, and because they don’t think about it, no one’s doing anything to work to save these species.”