Where do Acorns Come From?

In the wood behind the house stand many a mighty oak,
Leafless amid daffodils and April’s showery soak.
So many days, so many years, to passing season’s clock,
They’ve added rings beneath their bark made from this earth and rock.

Each weighty tree of solid wood was once a fragile shoot.
Sprang up amongst the winter brown. Drove down to hold and root.
See here, where shoot and root unite, an acorn small and brown.
That grew full ripe, high in the air, ‘til Autumn brought it down.

But ere the acorn cup grows full a magic spell unwinds,
Amongst the Springtime growth renewed within green leaves enshrined.
A promise of full future strength foretelling oaken powers.
Here with windblown leaf and twig the mighty oak tree flowers.