Ring Deformation (Compression Wood)

      An odd-looking ring pattern in a cross-cut log is explained as compression wood, certain to bend after sawing. April 20, 2011

Question
I am sawing up some pine beams and ran across a strange deformation in the rings. Anyone know what this might be? It runs the length of the 8' section I am sawing.


Click here for higher quality, full size image

Forum Responses
(Sawing and Drying Forum)
From contributor W:
The tree looks like it was bent over severely for a couple of years, then re-straightened by the hands of humans when it was very young. That does not look like any type of natural process that I am familiar with assuming that I am seeing what you intended to be seen in the photo.



From contributor B:
Looks to me like the tree had some damage to that spot when young, maybe from another tree falling along it and gouging the wood; at that point the tree would have been all sapwood, and could generate enough repair to seal itself up before any rot started in. Looks like it took two years, maybe three. The small blackish hole will probably lead to some defect, but I doubt it will be much.


From contributor S:
Looks like the blister caused by gall rust to me.


From Gene Wengert, forum technical advisor:
It looks like compression wood, which is a form of reaction wood. The tree is reacting to an outside force, such as a fallen tree.


From contributor A:
Compression wood. If you need rockers for a chair then q-saw that area and they will bend for you with no effort. Since you are cutting beams put that area in a corner. It will have less effect on the timber that way. My guess is that is in the bottom eight feet of the tree. I try not to use that portion of the tree in a timber or post unless it is very large.


From Gene Wengert, forum technical advisor:

Contributor A makes a very important point. Compression wood is so weak that it should never be used in a structural piece.



From the original questioner:
Thanks guys. That makes perfect sense. WOODWEB does it again! Love this place!



Would you like to add information to this article?
Interested in writing or submitting an article?
Have a question about this article?


Have you reviewed the related Knowledge Base areas below?
  • KnowledgeBase: Knowledge Base

  • KnowledgeBase: Primary Processing

  • KnowledgeBase: Primary Processing: Sawmilling

  • KnowledgeBase: Wood Engineering

  • KnowledgeBase: Wood Engineering: Wood Properties


    Would you like to add information to this article? ... Click Here

    If you have a question regarding a Knowledge Base article, your best chance at uncovering an answer is to search the entire Knowledge Base for related articles or to post your question at the appropriate WOODWEB Forum. Before posting your message, be sure to
    review our Forum Guidelines.

    Questions entered in the Knowledge Base Article comment form will not generate responses! A list of WOODWEB Forums can be found at WOODWEB's Site Map.

    When you post your question at the Forum, be sure to include references to the Knowledge Base article that inspired your question. The more information you provide with your question, the better your chances are of receiving responses.

    Return to beginning of article.



    Refer a Friend || Read This Important Information || Site Map || Privacy Policy || Site User Agreement

    Letters, questions or comments? E-Mail us and let us know what you think. Be sure to review our Frequently Asked Questions page.

    Contact us to discuss advertising or to report problems with this site.

    To report a problem, send an e-mail to our Webmaster

    Copyright © 1996-2016 - WOODWEB ® Inc.
    All rights reserved. No part of this publication may be reproduced in any manner without permission of the Editor.
    Review WOODWEB's Copyright Policy.

    The editors, writers, and staff at WOODWEB try to promote safe practices. What is safe for one woodworker under certain conditions may not be safe for others in different circumstances. Readers should undertake the use of materials and methods discussed at WOODWEB after considerate evaluation, and at their own risk.

    WOODWEB, Inc.
    335 Bedell Road
    Montrose, PA 18801

    Contact WOODWEB











  • WOODWEB - the leading resource for professional woodworkers


      Home » Knowledge Base » Knowledge Base Article