Red band on Black Butte not sign of dying

The trees on Black Butte are not dying.

A red band of trees is certainly clearly visible from Black Butte Ranch and other locations around Sisters, but it doesn't mean a fatal event. It isn't something you see every day, for sure, but if you ask old-time USFS employees of Sisters, Don Rowe, or Dave Moyer about it, they'll tell you they've seen it happen before over the years.

According to Brian Tandy, Sisters District Forester, and Tom Andrabe, State Forester, the phenomena you see on Black Butte is known colloquially as 'red-band,' the result of trees in the process of waking up coming into contact with very cold air trapped beneath a layer of warm air (known as an inversion). Most times, it works something like this...

Prior to the cold snaps we had just before Christmas, there were enough warm days to start the needles of trees on the south side of Black Butte to begin waking up. Even though the moisture was still frozen in the roots, the upper foliage of the trees thought spring was here.

Then the good old "Polar Express" rolled down the east side of the Cascades from the Far North around the 16th and again on the 22nd and the cold air may have been trapped under warmer air, causing an inversion. Nothing moves when this happens, the dry super-cooled air just sits there, freezing everything it comes into contact with; in this case, greening foliage of slumbering trees on the south slopes of Black Butte. (Evergreens have probably been going through this ever since the days of the Dawn Redwoods.)

Sometimes, an inversion will suppress convection (the vertical motion of air) by acting as a "cap," a phenomena that can lead to air pollution, such as smog being trapped close to the ground resulting in adverse effects on health. If this cap is broken for any of several reasons, convection of any moisture present can then erupt into violent thunderstorms; or at times, result in freezing rain. An inversion will, at times, also bend light rays, causing the mountains to look as though the summits have been flattened and "lifting" hills to unusual shapes.

In the mid-1960s a similar event took place near Mt. Hood, leaving a red band visible along the highway all the way from Government Camp to the Wapinitia cutoff. The frozen foliage around Mt. Hood dropped off in summer and was replaced by new growth, the same will probably happen on Black Butte, and in a couple of growth seasons things will look "normal" again.

That said, however, perhaps we'll see other interesting atmospheric events take place in the Northwest as the impact of Global Climate Change creeps up on us. Remember all those shingles flying through the air in January? The insurance companies, hardware stores and roofers do. So, keep your camera ready and your survival gear handy, that old Boy Scout motto is hard to beat: Be Prepared!