How long before a tree rots away?

[edfrank]

How long before a tree rots away?
July 30, 2012 - 07:15
By: Ida Korneliussen

http://sciencenordic.com/how-long-tree-rots-away

A fallen pine on the forest floor can take several hundred years longer to decompose than a spruce.

...But how long does it for the tree to vanish after having fallen down? And if a moose dies in the forest – how long until it has completely decomposed?

According to a Norwegian professor, some trees can last much longer than others, whereas carrion eaters, larvae and bacteria will dispose of a moose in a blink of the eye, relatively speaking.
Spruce goes first

“It can take 200 to 300 years for a downed pine tree to disappear, but most of a spruce will be gone within 50 to 100 years,” says Olav Hjeljord.

He’s a professor emeritus at Department of Ecology and Natural Resource Management at the Norwegian University of Life Sciences....

.

[Will Blozan]

Ed,

Jess Riddle and I cored yellow birch growing on a fallen hemlock log in the Smokies that were ~90 years old. The log was still above the ground level and not yet punky.

Will

[Joe]

Ed,

Jess Riddle and I cored yellow birch growing on a fallen hemlock log in the Smokies that were ~90 years old. The log was still above the ground level and not yet punky.

Will

again, I fantasize what the forests looked like before the pale faces showed up- there must have been a tremendous amount of "woody debris" in the forests, which made for an incredibly rich habitat- we have a hint from surviving old growth, but only a hint

and then we can fantasize before the Indians arrived and their forest burning....

the full richness of nature, of which we know so little

Joe

[Larry Tucei]

Ed, Will, Joe, I wish we could known how long the downed trees of Southern Forests lasted before the  arrival of Formosian Termites and many other insect Pests.  A tree falls here and in a matter of one decade to two it’s gone, three at the most.  Exceptions are some Pine Stumps they may last up to 50-75  years (close estimation). Cypress tree stumps as long as a century or more.  There may be other species that remain depending on location.    Larry

[Rand]

Ed, Will, Joe, I wish we could known how long the downed trees of Southern Forests lasted before the  arrival of Formosian Termites and many other insect Pests.

Larry

I remember being rather taken aback the first time I saw pine stumps slowly sinking into the ground from the termites, leaving a ring of bark behind.  Knock one over and it's basically hollow inside.

[Don]

My time in the Southwest supports the notion that ponderosa pines have remarkable decay resistance in part due to their extractives and in part due to the remarkably dry climate of the Southwest.  I know there are papers out there on how long, but I can't recall them off the top of my head.

I can however provide some anecdotal information.  My first year as a GS-3 Forestry Aide with the BLM in eastern Oregon, I served on a survey crew doing Original Corner Restoration. Using K & E Mountain Transits like the original surveyors used in the 1880's, with declinations corrected to match them, we used the original survey notes to as close as possible duplicate their survey line...many times we found their original Bearing Trees, and with the notes were able to identify original corners, (scribed rocks, preferably tall, four-sided rocks, scribed on each of the edges to assign location).  We occasionally found their intermediate chaining points (a branch lopped off at an angle at one end, stubbed off at the other, then hammered into the ground for distance measurement points) still intact.  Most remarkable, we occasionally would find planks the surveyors had fashioned to practice scribing the numbers and letters on Bearing Trees (such as SEC 1, T3N, R8E).

That was 1967, some 80 years after the passage of the original surveyor.  When they actually did survey the sections they were assigned.   But that's another story...; > }

It was a wonderful job for a guy starting out his career in Forestry, first time away from home, staying in remote government cabins for a week at a time, all in John Day River country.

[Chris]

Perhaps Native American use of fire in eastern forests would have reduced the amount of woody debris on forest floors.

However, we certainly do know that there was tons of wood in various streams and rivers [a great interest of mine] The 160 mile long wood debris raft on the Red River when Europeans arrived in early/mid 1800s in Louisianan is a great (although extreme) example. From what I recall, the research suggests some large pieces of wood could take a couple hundred years to decompose in streams [there are still large Chestnut logs in Appalachian streams], with a few last even longer [over 1300 years for a few in one study Pacific NW].

[Don]

Chris
Two different scenarios operating here, one of high relative humidities (Eastern forests) and low RHs (Western forests).  In the case of rafts of river run (or lakes for that matter) timber destined to mills, not only did the lumber companies transport their product by water, they stored them in ponds, for as long as they remained underwater, they wouldn't rot (same thing happens with wood buried in peat bogs, mud slides, etc. (think 'anerobic').  Thinking of Byzantine boats recently discovered by Nat'l Geo, with much of their wooden hulls still intact, after thousands of years.
-Don