If a tree gets planted and there’s an idling SUV nearby, does it still have a carbon footprint?

[IMGCAP(1)]That was the variation on the age-old question that HOH was musing after Speaker Nancy Pelosi’s security entourage showed up Tuesday afternoon for an eco-friendly Earth Day celebration.

“On this Earth Day, the greatest challenge facing the U.S. — and indeed our world — is global climate

change,”Pelosi said to a crowd of reporters. “We hope to lead by example.”

But the California Democrat’s example wasn’t exactly green. While Pelosi did walk from the Capitol to the tree-planting ceremony at the East Front driveway of the Capitol, she was accompanied by two gas-guzzling SUVs. A third SUV was parked nearby for House Majority Whip James Clyburn (S.C.), who also attended the event.

Initially, the vehicles, which follow Pelosi as part of her security detail, parked directly behind where the tree-planting was to take place, says an HOH tipster. After staff likely realized that having SUVs as the backdrop for photo-ops on Earth Day might be a little off-message, the SUVs moved ahead about 25 feet — out of the cameras’ range.

Still, although the vehicles may have been out of sight, as Pelosi talked about conservation, gas efficiency and the like, the lead SUV sat idling the entire time. Pelosi spokesman Drew Hammill defended his boss’s Earth Day activities, especially compared with President Bush’s cross-country commute.

“The Speaker walked outside to plant a tree and walked back. The president flew to New Orleans to plant a tree,” Hammill said.

And Pelosi is trying to make progress on the gas-guzzling of her SUVs. Carrie Hanley, a spokeswoman for the House Sergeant-at-Arms office, tells HOH that the Speaker has requested a hybrid vehicle.

“We know she definitely wants one,” Hanley said. But there isn’t a Chevrolet hybrid Suburban like the ones Pelosi now uses, Hanley said.

Clyburn, though, gets at least a few greenie points. His SUV did boast a “flex-fuel” logo, a signature that indicates a vehicle uses ethanol fuel.

Hey, even Kermit the Frog knows it isn’t easy being green — and he doesn’t have a security entourage.

Hastert’s Big Loss. Watching the weight yo-yoing of celebs like Nicole Richie and Kirstie Alley is something of a national obsession, nevermind all the hype over the weight-loss show “The Biggest Loser.” Washingtonians have their own closer-to-home poster boy for the dramatic slim-down: Former Speaker Dennis Hastert (R-Ill.) has been getting rave reviews for his newly svelte figure.

Hastert resigned his House seat in November, and post-Congress, he’s looking better than ever, spies say. Hastert, of course, is a former wrestling coach whose, er, husky figure once earned him The Washington Post’s unflattering comparison of being “a cross between actor Wilford Brimley and Jabba the Hutt.”

Now, folks who have seen Hastert recently — HOH hears he’s working on bringing the Olympics to Chicago and is embarking on a speaking tour — say he’s half the man he used to be. “You literally wouldn’t recognize him,” one former staffer tells HOH. “He’s down from his heavyweight size and looks like the trim wrestler he used to be.”

Hastert’s new bod is getting the thumbs up, and sparking just a little bit of envy, apparently. “Denny could fit right in with the cast of ‘Baywatch’ while the rest of us continue running on the treadmill at the gym without any results,” says Ron Bonjean, another former Hastert aide.

Talk about losing the majority (of his extra weight, that is).

HOH: The Contest! We’re extending the deadline to April 25 for the inaugural edition of HOH’s new contest feature, which we’ve dubbed “Heard Mentality.” We’ve gotten some great submissions so far, but we’re looking for even more.

The directions are simple: Submit your brilliant ideas to our reader challenge, get your entry printed in HOH, and win a stylin’ HOH T-shirt.

Here’s the challenge: In honor of this week’s Congressional Blues Festival, come up with the title and as many lyrics as you like for a Congress-themed blues song. Bonus points for anything that rhymes with “302(b).”

Mock Debate. While presidential candidates Sens. Hillary Rodham Clinton (D-N.Y.) and Barack Obama (D-Ill.) battled to the vicious end in the Pennsylvania primary on Tuesday, their doppelgängers were yukking it up in a far funnier fashion.

The three leading impersonators of the presidential candidates — actors who are paid to portray Obama, Clinton and presumptive GOP nominee Sen. John McCain (Ariz.) at various gigs around the country — got together to film videos they plan to post on YouTube featuring lots more laughs than the real campaign clashes.

The videos of mock debates and speeches, starring comedians Ron Butler (Obama), Frank King (McCain) and Jan McInnis (Clinton), will be posted on youtube.com/frankking2 and janishillary.com by the end of the week.

In the spoofs, the comedians riff on recent news, such as Clinton comparing herself to “Paulette Revere” in forecasting a dim economic future, and oldster McCain taking exception to the comparison. “Excuse me, Sen. Clinton. I knew Paul Revere. Paul Revere was a friend of mine. You are no Paul Revere,” King told HOH, offering a sneak peak of his material, after peeling his cell phone away from the prosthetic mask he wears to look more like McCain.

A debate that makes us laugh — on purpose? We get the feeling ABC will be jealous.

Briefly Quoted. “I am the antithesis of cool.”

— Former White House Chief of Staff Karl Rove, stating the obvious in an interview in the May issue of GQ.

Torey Van Oot contributed to this report.

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