The Naked Scientists

The Naked Scientists Forum

Author Topic: Do trees have an expected lifespan?  (Read 576 times)

Offline thedoc

  • Forum Admin
  • Administrator
  • Sr. Member
  • *****
  • Posts: 511
  • Thanked: 11 times
    • View Profile
Do trees have an expected lifespan?
« on: 09/06/2016 19:50:02 »
Bruce Rodgers asked the Naked Scientists:
   Do all/some trees have an expected lifespan?


Love the podcast!
What do you think?
« Last Edit: 09/06/2016 19:50:02 by _system »


 

Offline alancalverd

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 4696
  • Thanked: 153 times
  • life is too short to drink instant coffee
    • View Profile
Re: Do trees have an expected lifespan?
« Reply #1 on: 09/06/2016 23:40:49 »
Fruit trees seem to have a finite natural life expectancy but giant sequioas seem to go on until struck by lightning or landslide.

The London Plane, which first appeared as a hybrid in the 17th century, seems to be immortal. Apparently, whilst thousands have been bombed, burned or cut down, none has ever been observed to die a natural death. Problem is that, being an "architectural" species, they are planted and uprooted along with roads and buildings, or felled for construction timber, and there are very few truly "wild" ones to observe.
 

Offline Colin2B

  • Global Moderator
  • Neilep Level Member
  • *****
  • Posts: 1906
  • Thanked: 122 times
    • View Profile
 

Offline evan_au

  • Neilep Level Member
  • ******
  • Posts: 4093
  • Thanked: 244 times
    • View Profile
Re: Do trees have an expected lifespan?
« Reply #3 on: 15/06/2016 12:50:54 »
Individual trees have an expected lifespan.

However, some trees can grow by cloning themselves, and in this sense the "clonal organism" could have an indefinite lifespan. Algae also grow this way.

See: https://en.wikipedia.org/wiki/List_of_oldest_trees#Clonal_trees

The risk with a clonal organism is that once a pathogen successfully attacks one tree, the entire clonal organism is likely to succumb, as they have no genetic diversity. This is what is happening today to the worldwide Cavendish banana crop, which is a human-transported clone of a single banana tree.
 

Offline puppypower

  • Hero Member
  • *****
  • Posts: 553
  • Thanked: 42 times
    • View Profile
Re: Do trees have an expected lifespan?
« Reply #4 on: 15/06/2016 13:13:05 »
I saw a science special on the giant redwoods and sequoia in California. What was unique about these trees, is they get most of their water uptake through their leaves. They live along western California, close to the westerly winds off the Pacific ocean. They have adapted to extract water from the ocean mist, through their leaves, and don't have to rely as much on their roots for water. They are not limited by the ability of the roots to pump water to the tree tops.

One theory is the terminal size of trees; life expectancy, is usually limited by how well the tree can pump water from the ground. Once this becomes limiting, other problems arise leading to decline. The redwoods and sequoia solved this problem and keep chugging.

With redwoods, water starts at the top of the tree and flows downward under gravity. There is also an upward capillary action push. acting as a water brake. Ions and minerals are able to flow upward, driven by a concentration gradient and entropy. The pressure of the downward water, should impact the roots, pushing the roots outward and onward, while the leaking water, will provide local root water for ion solubility and water recycle. The bark is really thick, which may help against hernia along the sides due to hydrostatic pressures The redwoods may have solved the pumping problem allowing long life.
« Last Edit: 15/06/2016 13:16:34 by puppypower »
 

The Naked Scientists Forum

Re: Do trees have an expected lifespan?
« Reply #4 on: 15/06/2016 13:13:05 »

 

SMF 2.0.10 | SMF © 2015, Simple Machines
SMFAds for Free Forums
 
Login
Login with username, password and session length