This lovely fern has sprung up all on it's own in our yard. It's wedged under the fence between our house and the neighbor's-I swear it looks like it's growing right up out of the concrete.
Ferns are incredible plants. If you ever find yourself around a fern, dissecting microscope and lamp (yes, I realize that magical trio is probably rare in most lives), put a fern frond sori side up under the scope and watch what happens. Seriously, it's great. When the sori dry out they pop open like a pac-man and tons (thousands?) of spores fly out. These spores land on the ground and grow into the other life stage of the fern, the microscopic gametophyte that makes the sperm and eggs needed to make the plant we all think of as a fern.
(Fern gametophyte photo from http://www.uic.edu/classes/bios/bios100/summer2003/fernlifecycle.htm)Incredibly, ferns are able to survive and thrive in some really harsh urban environments. Blair found one growing way up in the air on the metal supports of the freeway. Last month the New Yorker published this article (by Oliver Sacks of all people) describing a fern hike in the middle of New York-not in the park, but right down the city streets. You all in New York have some fantastic urban naturalist stuff going on.