Ever consider urban foraging?

Dig it: there are actual edible-nut trees growing in Center City Philadelphia:

West side of 5th Street, facing northeast. In background, the
Wachovia Bank building on the north side of Market Street and
the 5th Street, west side entrance to the Market-Frankford El

And they are mature enough to bear fruit, in this case hazelnuts (filberts):

Squirrel bonanza!

Two minutes of foraging, enduring funny looks from tourists, and fighting off squirrels yields a tidy handful of hazelnuts:

No squirrels were harmed in the production of this photo

So let's open up a few and see what we find:

Ew

Not ready for prime time. Could be that the trees are a little immature, could be air pollution, could be that we should have been gathering nuts from the trees rather than the pavement. Windfall apples are best left to the bees, I'm aware; but I didn't think that was the case for hazelnuts, considering some of the video I found.

A quick, quick Google search tells me that I may have luck if I set them out to dry for a little while. So I've been placing that dish in a windowsill and letting the sun have at the nuts before I try them again.

We'll see.