Jayson Jacoby
The Baker City Herald

The wildfires that blackened huge swathes of sagebrush steppe in southeastern Oregon this month surely will rekindle the simmering debate over the effects of livestock grazing on the primarily public rangeland that was scorched.

This is a good thing.

The BLM, which manages the vast majority of those acres as well as quite similar land in eastern and southern Baker County, is obligated to try to find out why almost 750,000 acres, which includes vital habitat for the sage grouse, burned.

Moreover, the agency has a responsibility to revise its grazing rules should the post-fire probe show that such changes would likely reduce the risk of similar fires in the future.

There's ample evidence showing that cattle have contributed to the spread of cheatgrass, the non-native annual grass that is the most volatile fuel on the range and that helped this month's fires grow so rapidly.

Cattle and cheatgrass have both been present for more than a century, though; the cheatgrass probably arrived via contaminated grain in the late 1890s, according to a 1996 report by Mike Pellant, a rangeland ecologist with the BLM in Idaho.

Yet this month's fires surpassed in size any blazes over at least the past century - a period that included severe droughts as well as much larger herds of cattle and sheep than exist now.

This suggests that blaming livestock alone for the recent fires - a charge that's been leveled by, among others, the well-known Oregon environmental activist Andy Kerr - might at least be overly simplistic.

Ranchers, meanwhile, contend that too little grazing, rather than too much, is largely responsible for the severity of this month's fires.

Had the BLM allowed cattle to munch more of the grasses and other fuels, the ranchers argue, then the blazes would have been easier to douse.

This explanation is plausible, though hardly definitive.

Cattle will eat cheatgrass in early spring, before it dries and becomes unpalatable. Grazing won't get rid of cheatgrass - indeed, as we said, livestock can spread the pestiferous plant through their manure and by carrying its seeds in their hair - but well-timed grazing can thin cheatgrass so that there's less to burn come summer.

It's possible that the heavier grazing pressure in the first half of the 20th century, while hastening the cheatgrass invasion, simultaneously limited the fire risk because there were so many animals on the range that cheatgrass rarely reached the density and height that exist in many places today where far fewer livestock graze.

Ultimately, we doubt any single culprit will be implicated in the fires that charred parts of Malheur and Harney counties this month.

We hope, though, that in the aftermath we'll enrich our knowledge and, as a result, improve our strategy for managing these vast lands which we expect to support rural economies as well as a variety of other values.