EARTHWORM aka NIGHTCRAWLER (Lumbricus terrestris)

The largest of earthworms, and from 111-300mm - more at link below.
Middens are made of castings and leaf petioles (or similar sticks or stems). Nightcrawlers don't feed in the ground but come to the surface to collect food. The sticks found in the middens are what's left of whatever they drag back down into the ground. Sometimes leaves will still be attached to the stems. They also bring up small stones to the entrance.
-*any* worm without a clitellum (band) is immature and cannot be identified
-pointed (conical) head and round tail
-body color dark brown-black, red-black, or red
-distance between nose and start of clitellum is greater than (>) 2 cm
-body is flattened
key here:
https://www.naturewatch.ca/wormwatch/wp-content/uploads/sites/5/2014/09/taxonomic_key.gif
(The labeled, pictorial, key is only allowed for classroom use so I can't reproduce it here.)
Earthworms and gardening: http://davidkusel.com/farm/nightcrawler1.htm
another site:
"As Lumbricus terrestris pulls leaves down into its burrow, the leaf stems (called petioles) and fragments of leaves, pile up at the borrow entrance. In addition, nightcrawlers deposit cast material (earthworm poop) at the surface surrounding their burrow entrance."
http://www.nrri.umn.edu/worms/identification/ecology_groups.html
and:
amaze family and friends, become a worm whisperer (worm fiddler):
http://www.outdoorlife.com/blogs/newshound/2008/10/worm-fiddling-here%E2%80%99s-science