Trees for water-logged soil

Discussion in 'Woody Plants' started by Dark Ant, Jan 30, 2007.

  1. Dark Ant

    Dark Ant Member

    Messages:
    14
    Likes Received:
    0
    Location:
    Merrist Wood, England
    I have just planted a Metasequoia glyptostroboides in a fairly water-logged field. Unfortunately, after heavy rains a puddle of water tends to gather around it's base to a depth of an inch, and it can take up a day or two to drain away. I'm worried this might cause the base of the tree to rot. Or maybe the roots. Should I replant my tree on slightly higher ground?

    How do willows manage to sit in so much water without their roots rotting? Do their roots differ to trees that prefer well-drained soil?
     
  2. Michael F

    Michael F Paragon of Plants Forums Moderator 10 Years

    Messages:
    11,417
    Likes Received:
    501
    Location:
    Britain zone 8/9
    Metasequoia will do very well in that situation, it likes wet soils.

    Yes, different trees differ markedly in their soil drainage preferences for good growth. For many trees, the ability to grow in waterlogged soil is enabled by their ability to transport oxygen through the roots.
     
  3. Dark Ant

    Dark Ant Member

    Messages:
    14
    Likes Received:
    0
    Location:
    Merrist Wood, England
    Thank you very much Michael. But can anyone explain the science behind Willow's ability to transport more oxygen. How exactly do they do it?
     
  4. Buckthorne

    Buckthorne Member

    Messages:
    12
    Likes Received:
    0
    Location:
    Northeast Harbor, ME, USA
    I can't help with the science but I can help others who might read this thread because they'd like a plant for a soupy area.

    When planting a nursery grown plant into a wet enviroment, it's often better to plant it a bit higher than normal. A nursery grown plant has not developed a root system that is broad and surficial. Instead, much of it will be deep in the pot or ball. Planting in a wet enviroment subjects these roots to an anaerobic enviroment that they can't adjust to quickly. This can often lead to massive die back in the crown and root system.

    Such plants might recover in several years so don't give up all hope. Just plant higher the next time.
     
  5. Dark Ant

    Dark Ant Member

    Messages:
    14
    Likes Received:
    0
    Location:
    Merrist Wood, England
    Hi Michael, thank you for your earlier answer above which I am still trying to understand. When you refer to willow's 'ability to transport oxygen through the roots' does this mean the transport system itself is better constructed than in other types of tree, or that willow can access more oxygen / and perhaps in a different way to other trees?

    Any pointers anyone can give me would be much appreciated. I'm beginning to plant up a very water-logged site and I'm trying to understand the science behind why some trees will do better there than others.

    Can anyone help?
     
  6. smivies

    smivies Active Member

    Messages:
    793
    Likes Received:
    0
    Location:
    Kingston, Ontario, Canada
    It varies from genus to genus but the tolerance of roots to low oxygen environements could be due to various adaptations including:
    - lower requirement of oxygen in the roots (ie. anaroebic)
    - bald cypress knees
    - air canals in Arundinaria gigantea var. tecta rhizomes,
    - willows produce air filled roots
    - produce lenticels (tiny bark openings allowing air into the plant tissues)

    Virginia Cooperative Extension

    Simon
     
  7. Dark Ant

    Dark Ant Member

    Messages:
    14
    Likes Received:
    0
    Location:
    Merrist Wood, England
    Thank you very much smivies! I'm amazed by all these cunning adaptations.

    I went to the library and did some research too and found out that willows and sunflowers develop a tissue called aerenchyma when oxygen levels are low. I think they can turn this ability on and off according to conditions. It's prompted by a gaseous hormone called ethylene and is developed in the 'above ground' parts of the tree. Apparently it's very fibrous and can hold a lot of oxygen in the airspaces - and this oxygen then travels into the tree roots. Have I got this right? Is this how willow produces air filled roots? I'm not quite sure how the oxygen 'travels' though.

    I read about the 'knees' on Swamp Cypruses that grow above the soil / water and allow oxygen to diffuse down to the submerged roots. Do you think my Metasequoia would use a similar system? They both have that soft fibrous bark which I imagine is very good for respiration. Is this right?

    But in both cases it seems an amazing feat for plants to get air *down* to their roots, especially given the pressure of the surrounding water. Or doesn't external pressure effect the inside of a root?

    I don't suppose anyone knows how Poplars or Alders cope with excess water? Is it either of the systems above or something else?

    Thank you to anyone who can satisfy my curiosity...
     
  8. Ron B

    Ron B Paragon of Plants 10 Years

    Messages:
    21,250
    Likes Received:
    786
    Location:
    WA USA (Z8)
    If you look at a copy of The Hillier Manual of Trees & Shrubs you will see they have a list of 'Trees and shrubs suitable for damp sites'. The trees they list are

    Alnus
    Amelanchier
    Betula nigra
    Betula pendula
    Betula pubescens
    Crataegus laevigata
    Magnolia virginiana
    Mespilus germanica
    Populus
    Pterocarya
    Pyrus
    Quercus palustris
    Salix
    Sorbus aucuparia
     
  9. Dark Ant

    Dark Ant Member

    Messages:
    14
    Likes Received:
    0
    Location:
    Merrist Wood, England
    Thank you very much Ron. Great list and I'll check Hilliers out.

    Here's my question: if you wanted to pick a specimen tree for a waterlogged site what would it be?

    Thank you x
     
  10. Michael F

    Michael F Paragon of Plants Forums Moderator 10 Years

    Messages:
    11,417
    Likes Received:
    501
    Location:
    Britain zone 8/9
    I'd go for Metasequoia, too.
     
  11. Ron B

    Ron B Paragon of Plants 10 Years

    Messages:
    21,250
    Likes Received:
    786
    Location:
    WA USA (Z8)
    If you have the room your dawn redwood will be a fine choice. Since it sets a prehistoric theme maybe something else ancient, like the magnolia, to go with it. Or maybe not a tree. VanDusen Botanical Display Garden, Vancouver has a prehistoric theme garden that is one of the best parts of the facility. Dawn redwoods, coast redwoods and bald cypresses are joined by lesser plants such as various bamboos, twig dogwoods, gunnera...possibly there are photos online.
     
  12. Buckthorne

    Buckthorne Member

    Messages:
    12
    Likes Received:
    0
    Location:
    Northeast Harbor, ME, USA
    I'd second the Metasequoia. But I'd also consider a weeping Taxodium.

    Metasequoias grow almost as quickly as Salix but without some of the problems. Salix a. Britzensis has a place at my own home but that's because our winters are so long. That and American Larch prevails around here so the notion of another diciduous conifer here doesn't have the appeal that it might for others.
     

Share This Page