Who is the greenest U.S. president in history? That’s the question [green-business magazine Corporate Knights] put to 12 leading environmentalists and environmental groups, each of whom were asked to rank their top three choices. It might seem an unfair question. Insoluble, even. What counts as “green”? Is it love of nature or legislation passed? Do good intentions count or are results all that matter?

Given these conundrums, the results revealed a surprising degree of consensus. In our tally of votes, there was a clear winner — one president who dominated with 28 points. Second and third received about half that, with 15 and 13 respectively. Fourth place fell to seven points, fifth to just three. Of 44 U.S. presidents, just eight received a vote. It seems environmentalists agree on these matters.

Before you read on, see if you can guess the top three. No peeking!

That’s the beginning of a piece I wrote in Corporate Knights magazine this month, part of a package that includes the survey of environmental groups. The presidents who got the most green votes:

  1. Teddy Roosevelt
  2. Richard Nixon
  3. Jimmy Carter

Read my piece to find out why.