I am the earthworm, Lord of the Underworld

I am the earthworm
Lord of the Underworld;
you hardly think of me
except perhaps as angleworm

I give the earth nitrogen
phosphates and potash;
and the soil is rich for
all my muscular contractions

I create passages for air
and water;
and by sheer power of my burrowing
I bring all these together

and if you think
I'm just tube
and mucus that I secrete,
sweetheart,
wait till you come
to the earth
for I'll break you down
and convert you
into humus and casts

O, I am the earthworm
Lord of the Underworld;
you hardly think of me
except perhaps as angleworm

so when are you coming,
sweetmeat,
when are you coming
down to earth?