From Terence Chea of the AP:

One year after failing to win control of the Sierra Club in a bitterly contested election, advocates for stricter immigration limits are back, arguing that the venerable conservation group can best protect the environment by reducing U.S. population growth.

The club's 750,000 members are voting this month on whether the organization should push for tighter restrictions on immigration. Five seats are open on the 15-member board of directors, which sets club policy and commands the $100 million annual budget.

Sierrans for U.S. Population Stabilization, club activists seeking to limit immigration, are backing five candidates and pushing a "yes" vote on a measure calling for restricting immigration...

But opponents, including many current and former leaders of the 113-year-old club, argue that wading into the politics of immigration will alienate allies such as labor unions and civil rights groups and won't slow population growth worldwide...

There might be a much more basic reason why the Sierra Club brass doesn't want to deal with this issue.

"Who's behind the smears?" discussed the case of David Gelbaum, who said "I did tell Carl Pope [Executive Director of the Sierra Club] in 1994 or 1995 that if they ever came out anti-immigration, they would never get a dollar from me..."

Gelbaum has donated at least $100 million to the Sierra Club.

Terence Chea would have mentioned this in his article, except Lexis-Nexis was down or something.

UPDATE: I originally said Pope had left the Sierra Club, but it turns out he's still there.