Here's one of my favorites ("Hyla" is a breed of frog that inhabits the brook); I especially love the poignant last line:

HYLA BROOK

by Robert Frost

By June our brook's run out of song and speed.
Sought for much after that, it will be found
Either to have gone groping underground
(And taken with it all the Hyla breed
That shouted in the mist a month ago
Like ghost of sleighbells in a ghost of snow)--
Or flourished and come up in jewel-weed,
Weak foliage that is blown upon and bent
Even against the way it's waters went.
Its bed is left a faded paper sheet
Of dead leaves stuck together by the heat--
A brook to none but who remember long.
This as it will be seen is other far
Than with brooks taken otherwhere in song.
We love the things we love for what they are.

By the way, you lovers of verse might well enjoy a great site I frequent: <eMule.com> The Poetry Archives
They have over 3,500 classic poems archived (mid-20th Century and back), and an interesting and lively discussion forum. So click on over and maybe I'll meet you there!