Sad about SAD.

Sudden Aspen Decline

Aspen Trees Die Across the West

This should be the golden season across the West, when aspen paint hillsides in shades of fall.

But a mysterious ailment -- or perhaps a combination of factors -- is killing hundreds of thousands of acres of the trees from Nevada, New Mexico and Arizona through Utah, Colorado, Wyoming and into Canada, according to the U.S. government and independent scientists.

The aspen die-off comes on the heels of a pine-beetle invasion that has destroyed millions of acres of evergreens. Foresters expect to lose virtually every mature lodgepole pine in Colorado -- five million acres of them.

Aspen and lodgepole pine intermingle across many Rocky Mountain slopes at elevations of 5,000 to 8,000 feet. Millions of the trees are now down or brown, transforming the landscape into a huge fire risk. To the dismay of hunters, the dying trees are decimating habitat crucial to elk, as well as to such smaller animals as wolverine, lynx and yellow-bellied marmot.

The article continues:

What is killing the aspen is unclear.

In 2002, the U.S. Forest Service began investigating reports that entire stands of aspen were dying in the San Juan Mountains in southwest Colorado, and in an odd way. Usually when mature aspen fail, they send out hundreds of new shoots, called suckers, through their root systems. Those shoots sprout quickly, and the grove regenerates.

But in the San Juans, the shoots were dying, too, or were failing to sprout. That phenomenon was named Sudden Aspen Decline, or SAD, but scientists say they don't fully understand it.

Doesn't sound too good, does it?

See also:

Aspen fading fast
Fall Colors Fade In U.S. West As Aspen Trees Die
Vanishing Aspens

[edit on 14-10-2009 by loam]

i really thought this was going to be a thread about Seasonal Affective Disorder.

Theories abound. I think I like this one best.

www.msnbc.msn.com...

Another Forest Service researcher, however, said there is no conclusive evidence of any long-term decline. In fact, Claudia Regan said it appears the number of aspen in Colorado has actually increased in the past century.

If there is a decline, it might be a natural correction to human interference, University of Wyoming botany professor Dennis Knight wrote in a paper for the Forest Service back in 2001.

“Widespread disturbances caused by timber harvesting and fires in the late 1800s and early 1900s may have enabled aspen to become unusually abundant in the Rocky Mountains,” he wrote. “If aspen is now declining, the explanation may lie in natural processes. ... There is no basis to suggest that aspen is threatened globally, nor are most aspen groves likely to be lost in the near future.”

It could very well be a natural cyclic event.

The way the tree regenerates is different than the way the tree reproduces. Check this out.

lewis-clark.org...

Aspen life strategy

Aspen’s broad distribution is not due to tolerance toward a range of climates. Just the opposite. It has a narrow range of environmental tolerance. But it produces trillions of wind-disseminated, short-lived seeds each year with the probability that one will land in a suitable environment, germinate, and develop into a sapling. This life strategy is referred to as “fugitive” species--many seeds scattered so one will land in a rare but suitable refuge. The requirements for successful germination and seedling establishment are so exacting that the probability of success is near zero. The secret is that when a rare seedling establishment occurs, the sapling develops into a grove that may persist for hundreds or even thousands of years by periodic rejuvenation.

Aspen seed requires a flat seedbed that remains moist throughout the summer, free from shade, and free from browsing by wildlife. The last time such seedbeds occurred on a wide scale was on protected silt beds left by retreating glaciers at the end of the ice age. Most of today's aspen groves are believed to have originated at that time, rejuvenating periodically over the ten millennia since the original seeds germinated. If age is calculated from seed germination, these groves are America’s oldest living trees, even though the aboveground portions are generally younger than 100 years.

Also..from the same source.

Leaves of the aspen produce a hormone called auxin that inhibits the development of lateral root buds. As the grove develops, enough hormone is produced and transferred to the roots that sucker buds become dormant.

Maybe this is a factor inhibiting the regeneration? It's possible that as soon as the stands are decimated enough to reduce the concentration of this hormone in the roots, the stands will bounce back.

So, definitely an interesting story to follow, but I tend to think positively about changes of this sort in the environment. Just because we don't understand the mechanism, or the larger context in which the change takes place, doesn't mean the change is a bad thing.

reply to post by WyrdeOne

Originally posted by WyrdeOne
...I tend to think positively about changes of this sort in the environment. Just because we don't understand the mechanism, or the larger context in which the change takes place, doesn't mean the change is a bad thing.

Quite true and well put.

However the timing of the decline with the pine beetle infestation is less than ideal. Moreover, the reports of impact to local ecology sound rather extreme.

While some change may be a good thing, rapid change is rarely so.


[edit on 14-10-2009 by loam]

I dunno - rapid change is not unprecedented in nature.

Look at the flowering bamboo - a stand of a certain bamboo species can exist for 60-100 years or more, and then one day they all just flower and die, across whole continents, practically overnight. It might be a decade before the bamboo comes back, but it always comes back.

Being that we're city builders we tend to value the stability of stasis more than the uncertainty of change, and we're most comfortable thinking in linear patterns, this kind of stuff is scary. That said, there is plenty of stability to be found in the cycles of nature, we just have a hard time appreciating it. It's outside our comfort zone = the range is too big and the scope too large.

We live a hundred years, give or take twenty. About as long as the bamboo...

A tangent here on the pine beetle...

Let's play worst case scenario.

The pine beetles, along with the consequences of human activities like fire control, conspire with climate change and the natural life cycle of the aspen trees to completely decimate the western forests. When the forests die, species migrate or perish (including the pine beetle), at the very least population levels suffer a major correction. No more forests means unchecked runoff from snowmelt, which leads to rivers overrunning their banks, resulting in widespread crop loss and soil erosion. A few decades of unusually wet winters exacerbate the problem and completely change the face of the rockies and the flood plains they feed. Time passes, drought returns, the floodplains become silt flats, the silt flats provide the perfect place for new stands of aspen to grow...

I'm just playing devil's advocate here, obviously, but I do it to make a point.

I truly believe that if we are to have faith in anything, we ought to have faith in the ability of the earth to get along just fine without us, even despite us.

[edit on 15-10-2009 by WyrdeOne]

Originally posted by MR BOB
i really thought this was going to be a thread about Seasonal Affective Disorder.

Me too. I suffer from Seasonal Affective Disorder and it's kicking into full gear now. ;( Would be cool to see how many others have this and what they do to help through out the dreary, gloomy, dark, and crappy winter days.

reply to post by WyrdeOne

Originally posted by WyrdeOne
I dunno - rapid change is not unprecedented in nature.

...

Being that we're city builders we tend to value the stability of stasis more than the uncertainty of change, and we're most comfortable thinking in linear patterns, this kind of stuff is scary. That said, there is plenty of stability to be found in the cycles of nature, we just have a hard time appreciating it. It's outside our comfort zone = the range is too big and the scope too large.

...

I'm just playing devil's advocate here, obviously, but I do it to make a point.

I truly believe that if we are to have faith in anything, we ought to have faith in the ability of the earth to get along just fine without us, even despite us.

In many respects, you and I agree on much of these points. I have no doubt the earth can get along just fine without us.

However, when I discuss the notion that rapid environmental change is rarely a good thing, I do so almost exclusively in the context of the benefits and costs to humanity. I'm not your typical 'PETA-esque' type of environmentalist, whose concerns are for 'god's little creatures'... (I think my posting history soundly demonstrates that point. )

In my view, understanding environmental change and responding to it appropriately are forms of self preservation.

Maybe that explains my perspective more clearly.

So, in that regard, I guess I'm 'Sad about SAD', because it represents yet another poorly understood change, that if wrongfully under-appreciated, could bite us in the collective ass.


[edit on 15-10-2009 by loam]

I hope this doesn't mean the end of these beautiful trees. I lived in Aspen for a couple of years a while back, and the trees were so magnificent.
The white trunks and lime green leaves. Beautiful.

I once packed a small one in my suitcase! I put it in a plastic bag of moist dirt, put it in my suitcase and brought it back on a plane. lol. I planted it on my parents front lawn. But, alas. It didn't survive.
Too hot, I suppose.
Whatever is wrong, I hope they find the cure. It would be a shame to lose these beautiful trees.

reply to post by loam

In my view, understanding environmental change and responding to it appropriately are forms of self preservation.

Maybe that explains my perspective more clearly.

Ahh..a very valid point.

And yes, it does make me better understand where you're coming from.