20 Feb 2008, 5:04pm
Ecology
by admin

Late Succession Is Eco-Babble Nonsense

by Mike Dubrasich

The horrendous megafires that are punishing our landscapes arise in what many call “late successional stands”. Government vegetation maps indicate that the most fire-prone areas are designated late successional. The government has incorporated the term late successional into our legal system. It is a land use class, much as commercial, industrial, or residential zones are designated on urban zoning maps.

Many forest scientists maintain that late succession is some sort of ecological state or condition. And not just any condition; late succession is the cat’s meow, the most treasured condition that forests can attain. We have shut down and locked up tens of millions of acres of our public forests because they are or soon will be (we hope) late successional. Nobody talks about old-growth anymore; the term of art is late successional.

It therefore behooves us to try to figure out what the heck “forest succession” is and when it becomes “late.”

But that is a fool’s errand, because forest succession is itself a bogus concept.

Ideally, in the eco-babble dream world, forests begin as bare ground, totally seared to the dirt, with nothing alive above ground. First “pioneer” plant species move in, followed by “settler” species, and eventually “climax” species take over.

That’s succession, a gradual change in species, particularly tree species, until a stable, “climax community” of plants is established and sets there, unchanged, for the rest of time.

It is similar to the succession of kings to a throne. The first king named Henry is Henry I. When he dies, another king succeeds him. And then that king dies, and somebody else succeeds him. Eventually, if enough time passes, you might see another King Henry, and then another, all the way up to Henry the Eighth or even more. Of course, no king lives forever, so no climax stable kinghood ever comes about.

That’s true in nature, too, obviously. No tree lives forever. The theory of forest succession accounts for that: the individual trees may die, but the species eventually stop changing, and that is the climax state. Of course, eventually and inevitably another disturbance occurs, and then the whole successional parade starts over.

The problem with the theory of forest succession is that it does not occur in nature. It is a phenomenon that occurs only in the minds of dreamers. The real world is quite different than that.

In the real world when a major disturbance occurs, such as a catastrophic wildfire, indeed the vegetation can be burned to the ground. Immediately after the fire, in the smoking ruins, nothing is left alive. So that part can occur.

Following such a fire, two types of subsequent plant occupation happen: some plant species sprout from living root systems, and some plant species germinate from seeds. Then those plants grow. Eventually they might get to be big plants, as in fat, tall trees, or they might die from the competitive stresses brought on by the other plants around them.

Then another fire happens, and it starts all over again.

There is no evidence that other plant species, that weren’t there in the first place, move in and take over. If the seeds or sprouts weren’t there in the first place, they do not show up later. No succession of species happens. So-called “climax” species don’t blow in from somewhere else.

Ubiquitous (ecologists say “cosmopolitan”) weeds might blow in, especially right after the fire, but weeds are pioneers, not settlers or climax species. Weeds do not take over later. Nothing exotic to initial conditions takes over later. If the dominant tree species weren’t there in the first place, they never get there.

There are exceptions to this general case:

1. Following the Wisconsin Glaciation, as the ice retreated, vast tracts of bare dirt were exposed for the first time in tens of thousands of years. A great deal of plant migration occurred in the first few millennia of the Holocene. But then the ground became occupied, and the plant migrations largely stopped.

2. Human beings have transplanted or carried species from other places that sometimes became established in a new place, and then grow more or less like they were always there. Oak species and western red cedar are examples of human-spread tree species in Oregon. Other human-spread, non-indigenous, tree species around the world include cocoanut, candlenut, breadfruit, apple, holly, laurel, poplar, and Douglas-fir.

Even when non-indigenous species are present, if a patch of seared ground does not have the plant species in or near it from the get-go, those absent species do not show up and take over that patch years later.

The theory that plant species move in later is known as “relay floristics.” The idea is that forest succession is a long-distance relay race, and the baton is handed off to next species after a few laps around the track.

Relay floristics does not occur in nature, however. It is a myth. Indeed, the term relay floristics was invented to disprove and dispel the alleged phenomenon. The actual thing that happens is termed “initial floristics” which means the species were there from the time of initial post-disturbance colonization.

Even so, the theory of initial floristics also implies that the dominant tree species change over time. The species were all there at the beginning, but some species (the sun-loving ones) shot up quick and dominated, and then other species (the shade-tolerant ones) gradually took over.

That doesn’t happen, either. For example, the Coast Range when the first pioneers arrived was thought to be covered by an untouched, unmanaged, virgin forest that had been there for millions of years. According to theory, western red cedar and western hemlock should have dominated. But they didn’t. What the pioneers encountered was Douglas-fir.

There is and was western red cedar and western hemlock throughout, but the bulk of the trees were Douglas-fir of about 300 years old. Now we know that all the conifers were relatively new, existing in the Coast Range only after the retreat of the Wisconsin Glaciation. Still, 11,500 years should have been plenty of time for succession to have happened and the shade-tolerant species to have dominated, if succession is a real phenomenon.

Cedars and hemlocks did not dominate, essentially proving that forest succession did not happen, at least not according to the text book theory. For instance, Natural Vegetation of Oregon and Washington by Franklin and Dyrness identifies the Coast Range as the Tsuga heterophylla (western hemlock) Zone:

Numerous examples can be found of mixed old-growth Pseudotsuga-Tsuga (Douglas-fir-western hemlock) forest in which abundant seedlings, saplings, and poles of Tsuga heterophylla are present and those of Pseudotsuga are completely lacking. However, there is some variation within the zone regarding the climax tree species. On environmentally median sites, Tsuga heterophylla appears to be the sole climax tree species… On wet to very wet sites, Thuja plicata will certainly be a part of any climax forest.

Yet climax western hemlock and western red cedar was not what was there when the pioneers arrived. They found Douglas-fir dominating.

In the Northwest Forest Plan much of western Oregon and Washington forests have been characterized and mapped as “late successional.” Yet no succession has taken place. Not only that, the trees standing there now are the pioneer trees. Not only has King John not replaced King Henry, King Henry is still there. The exact same trees that pioneered the sites are the late successional trees of today.

No succession of species has occurred. Indeed, no succession of individual trees has occurred. What is called and mapped as late successional has experienced no succession at all!

If any eco-babble name can be applied, those stands are early seral, meaning the pioneer trees are still there.

Late successional has now been defined to be any stand of pioneer trees over 80 years old. Yet Douglas-firs will live to be over 1,000 years old. The 80 year-old babies are termed “mature” and “over-mature” trees. That is subjective nonsense.

Douglas-firs don’t mature like grapes or fields of wheat. They just keep growing. They never senesce. Sometimes their tops get blown out, but they don’t get weak and crotchety like people do. If they don’t burn up or blow over, eventually rot sets in from broken tops or branches, and they die. All trees die eventually, but our long-lived western conifers don’t turn grey and their bones start to weaken. Their teeth don’t fall out.

Much of the forest land that been classed as late successional has some old-growth trees on it. Old-growth is not a successional condition. It merely means old trees. And “old” is another subjective judgment. It used to be that a tree had to be 200 years old to be classed as old-growth. Now the designation has to do with the size of the tree, i.e. any tree over 2 feet in diameter. Yet a healthy Douglas-fir can reach that point in less than 30 years.

Millions upon millions of acres have been classed as late successional that have nothing but baby trees on them. Moreover, succession has not occurred on those acres, and may never occur, at least not in the textbook sense.

Forest tree species change is occurring in some forests. Typically in multi-cohort stands, the old trees are ponderosa and sugar pines with a few Douglas-firs and other conifer species, and the young trees are Douglas-firs and grand firs. A type of succession is occurring, from pine to fir. But when those stands burn up, they don’t renew as pine stands. They go straight to fir.

Open, park-like stands of pine do not arise in nature, not at this point in history, not in the wild, not in the “unmanaged” forest. The only way to make an open pine stand is with human inputs, like regular, seasonal, frequent, light underburning. Thinning helps, too. But Mother Nature by herself doesn’t do that.

The older cohort trees exhibit all the characteristics of open-grown trees: wide growth rings near the pith, large limbs and knots to the ground, low height/diameter ratios. In contrast the younger cohort trees are distinctly stand-grown: narrow growth rings at early years, small knots and limbs with none near the ground, and large height/diameter ratios. Moreover, almost all the old trees have fire scars, and the young ones don’t.

People did that. People set the fires that induced open stands of open-grown trees. Mother Nature didn’t.

Sometimes the anthropogenic fires were severe enough to eliminate all the trees. An example: Grass Mountain near Coos Bay. Today Grass Mountain is covered by 100 year old Douglas-fir. But 150 years ago it was almost all prairie. Hence the name, attached by pioneers. There is no record of any fires there. There is little lightning and no lightning fires. There are no remnant older trees. No logging has occurred on Grass Mountain. Trees grow great there, as evidenced by the Douglas-firs growing there today. Yet it was all grass. How did that happen?

By the way, Grass Mountain has been nominated by Rep. DeFazio and Sen. Wyden to be a wilderness area. Is it untrammeled? Untouched by man? On the contrary, it was home to people who torched it every year for at least many hundreds, possibly thousands of years. There are camas ovens in the area that date back ~4,000 years. Hardly any camas grows there now. Camas is a prairie plant. The prairie is no more. It was a human-induced prairie. Without the fires it has “succeeded” to baby Douglas-firs.

Forest succession does not appear to happen in nature, for the most part, at least not in the textbook sense. Moreover, what is classed as late successional is not in any way, shape, or form.

Late successional is a bogus concept that has been written into numerous laws. Congress has totally misconstrued what is going on in our forests. Sadly, it has been forest ecologists who have generated the confusion.

Late succession is no more real than the storks-deliver-human-babies theory.

We live in a highly deluded era, not unlike the Dark Ages. Wild-eyed superstitions and myths govern us. The fawning over late succession is a prime example. Many people believe that without late successional forests, all of nature (and humanity, too) will cease to exist. Spotted owls are thought to dependent on late successional habitats and the species will go extinct without them.

Yet the so-called late successional forests are not that. They are pioneer baby tree forests. Succession hasn’t happened and likely won’t.

As I write this, I know that 99 percent of the people who read it will not believe it, will recoil in shock and dismay, and probably have stopped reading long before this sentence. If you got this far, good for you. You have received some myth-busting truth. And though you may not know how, and neither do I, someday that truth will set you free.

Late succession is eco-babble nonsense. Count on it.

 
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