Robert Hass is profiled in The San Fransisco Chronicle. His new book Time and Materials: Poems 1997-2005 was nominated this month for the National Book Awards.
If you were to ask me what my favorite poem of all time is, I wouldn't hesitate to say "The Apple Trees at Olema" from Hass's book Human Wishes (1989). There is so much going on in the poem that I could read it over and over without ever getting tired of it.
I can't seem to find an online version of "The Apple Trees at Olema" but you can read an excerpt of it in an older article from The New York Times here. You have to read the whole poem to really appreciate it but at least you get a bit of an idea of what it's like.