The Fireflies

There are fireflies at the tops of the trees tonight—
  too high for any kid to catch
  the way we used to do, in a Mason jar or
  lacking one of those, a paper bag from
  the downtown department store.

 Your bag or jar would glow, and you
  could bring it back to the porch where
  you’d sit and swing back and forth, back and forth,
  with your beetle-powered flashlight.

Why do they fly so high these days?
  have they evolved to escape the grasp
  of children running barefoot on the ground?


Or is it just colder down here below,
  several  latitudes north of where I grew up?

I don’t know.