Just as forest edges create productive ecotones, so do the
places where dense building gives way to open or lightly
managed ground — the edge of a city, the last row of houses
before fields begin, an industrial estate bordering scrubland.

These zones often carry a layered history — partially developed,
partially abandoned, sometimes built and unbuilt more than once
over decades. This disturbance history tends to produce a wide
mix of plant species, since different patches may date from
different points in that history.

As covered in section 2.5, these transitional areas sometimes
carry contamination risks from past industrial or agricultural use.
Before foraging seriously in a new urban-rural edge, it's worth
finding out a little about what the land was used for previously.

These edges are frequently overlooked by other foragers,
who tend to gravitate toward more obviously "natural" looking
forest or meadow. That makes them genuinely good places
to find abundant, untouched patches close to home.