This is a Tanka, a short Japanese classical poem, by Minamoto-no-Yorimasa.
If you've read the 'Heike Monogatari', the famous war tale or the military romance of the medieval period, Yorimasa may have impressed you as a trustworthy and tragic samurai hero.
At that time he was also known as an excellent poet. He was especially good at describing nature's beauty.
If you'd like to try your hand at translating the above poem, please e-mail me. I may be able to help you in the reading.