A SIMPLE FACT: NATIVE-BORN AMERICANS ARE KNOWN TO HAVE STARTED RECENT WILDFIRES IN ARIZONA

You probably know that John McCain has claimed to be aware of "substantial evidence" that Arizona wildfires were started by illegal immigrants -- and that the Forest Service has denied that there's any such evidence. Salon has a follow-up to the story, which includes an attempt at a clarification by a McCain aide, but that attempted clarification doesn't help McCain's case much:

... I inquired about it with his spokeswoman, Brooke Buchanan. She told me in an email Sunday that the senator "was given the information by a Forest Service official during his visit to the Wallow fire damaged area on Saturday." ...

A spokesman for the agencies fighting the Wallow fire, however, told ABC that while the fire is believed to be human-caused, he knows of "no evidence" that illegal immigrants were involved.

Buchanan says that McCain wasn't referring to the Wallow fire, but rather some smaller blazes at Coronado National Forest near the U.S.-Mexico border.

She points to comments earlier this month by Jim Upchurch, forest supervisor at Coronado, who told the Arizona Daily Star that closing the forest was necessary because "the great majority, if not all the fires, on the Coronado National Forest (this year) have been human-caused. Causes of fires include ricocheting bullets, campfires, welding equipment and possibly ignition by smugglers or illegal immigrants."

Upchurch said that smugglers or illegal immigrants "possibly" were involved in starting some of these fires. What's not noted in the Salon piece is that we know some of the incidents Upchurch mentions definitely involved native-born Americans, as The New York Times reported on June 1:

Bill Edwards, the lead ranger at the Coronado National Forest, ... cited four other southern Arizona fires, all of them in known smuggling areas, that were found to have been caused by American citizens. One was caused by a rancher whose welding created a spark that ignited the dry underbrush, he said. Another was found to have been caused by target shooters. In two cases, he said, military aircraft engaged in training exercises set off fires.

(Emphasis added.)

I suspect that McCain's "substantial evidence" is nothing more than a belief that any fire started in a known smuggling area simply must be connected to illegal immigration. But the lead ranger at Coronado says definitively that that's not true.