The Wallow Fire in eastern Arizona has now burned through 639 square miles of forest — adding 114 square miles just in the last day and is now headed across the state line to New Mexico. It’s the second-worst fire in Arizona state history.

More disturbing: the massive fire may not have been nearly so large if the state’s forests had been managed responsibly. State and local officials across Arizona say that inaction by the U.S. Forest Service to properly thin federal forestland is contributing to the wide scale of the Wallow fire.

And it’s not just the U.S. Forest Service that has dropped the ball, according to the Oklahoman.

Some critics put the responsibility on environmentalists for lawsuits that have cut back on logging. Others blame overzealous firefighters who have altered the natural cycle of lightning-sparked fires that once cleared the forest floor.

Either way, forests that once had 50 trees per acre now have hundreds, sometimes thousands, and the landscape is choked with tinder-dry brush.

The density of the growth has fueled immense conflagrations in recent years like the 525-square-mile blaze now burning in the Apache-Sitgreaves National Forest northeast of Phoenix.

“I think what is happening proves the debate,” said state Sen. Sylvia Allen, R-Snowflake.

In the past, a 20,000-acre fire was considered huge. “And it used to be the loggers got right on it. Never in the past have you had these huge fires,” she said.

What’s particularly frustrating in Arizona is the state’s timber industry, environmentalists, local officials, scientists and the U.S. Forest Service reached a historic agreement after devastating wildfires in 2002. The Four Forests Restoration Initiative was supposed to allow restoration thinning on 2.4 million acres of ponderosa pine forests in the Apache-Sitgreaves, Coconino, Kaibab, and Tonto national forests — the exact region that is burning right now.

But the U.S. Forest Service dragged its feet on getting the project going. So much so that supervisors from five Arizona counties just published an op-ed today asking the Forest Service to fully implement the Four Forests plan.

The tragedy of the Wallow Fire in northeastern Arizona is a harrowing reminder that our national forests largely remain in the same unnatural and unhealthy condition that led to the Rodeo-Chediski Fire nine years ago. These conditions include a dangerous accumulation of undergrowth and an overabundance of small diameter trees that turn what should be cool-burning restorative fires into landscape-scale conflagrations that threaten entire regions.

…If implemented properly by the Forest Service, (Four Forests) has the potential to make such fires a thing of the past…

The alternative is a continuation of the status quo, with landscape-scale fires becoming the norm rather than the exception, until there is no more forest left to burn.

The anger in Arizona is not just coming from residents and elected officials but also science experts.

“Decades of scientific research reveal that the West is suffocating under too many trees,” Wally Covington, a professor of forest ecology at Northern Arizona University and executive director of NAU’s Ecological Restoration Institute, said in a statement. “Where we once had 10 to 25 trees per acre, we now have hundreds.”

…Covington warns that about 180 million acres (73 million hectares) of ponderosa pine across the West are at risk due to overgrown trees…

“Especially with drought and climate change, there is an urgent need to restore forests to their most resilient condition,” Covington said. “That requires protecting the old-growth trees and thinning most of the small-diameter trees.”