Cypress Knee Question Help Needed

[GeorgiaCarver]

I received the following question from a school teacher:

I have been unable to find the answer to a very simple questions....why are cypress knees so light when the trunk from a cypress tree is so heavy? I have school children to inform, and want to do so correctly. Hope you can help.

Help!!!!!

Anyone know the answer?

Greg

[GeorgiaCarver]

Any thoughts? I think it has to do with the fact that a tree as it grows has rings, sways back and forth compressing the rings (fibers). Knees on the other hand do not sway and are not subject to compression factors (weight from above, movement etc).

[Thomp]

dont know that answer but heres another to go along with it...

in the swamp next to a lot of cypress a tupelo gum grows in the same location, the trunk at the waterline is large and swollen 3 times or more than the log-trunk but about the same or a little tougher than cypress knees.. duck decoy carvers love this wood..

my father-in-law (an old woodsman of the world) said the softer wood allows the tree to bend in storms like springs...

[TreeWizard]

I believe that the knees are lighter than the rest of the tree since the knees are growths off the root and not the same as the wood that is grown in the trunk of the tree.

If you cut the roots of almost any tree you will fine the wood to be less dense, henceforth, lighter in weight than the wood from the trunk.