OK, I was sure of that, but I wanted to set a benchmark anyhow :winking:.
Freddie Harrison, from over in west Tennessee...he's one of the leading suppliers of stock blanks along with Wayne Dunlap... and I are pretty good friends since we have so much in common ie making our living in the woods, sawmilling, messing around with different woods,etc. I've asked Freddie how to tell if a tree has curl before it's opened up on a head saw,and basically he says: With a hatchet strip a chunk of the bark off above the root coller maybe a foot above the ground line cutting just into the white sap wood. Look this cut area over carefully from different angles getting a different light pattern on the wood, and if there is curl it will be seen though it is VERY SUBTLE. I don't know if this works or not since I've not tried it, but I'm betting that Freddie is right about it!
Now the question has been asked on another Thread what causes curl to form in some trees and not others.Many,many years ago when I had the required wood tech course in forestry school, I remember clearly what our wood tech Prof said about stripe and curl in maple, ash, walnut and other species. This may have changed with more advanced research in the past 45 years,but in a nutshell here's what old Dr.Hamilton told us in class:
Wood is made up of cells,naturally,and different cells have different functions. Most of a tree's woody cells are stacked end to end running up and down the stem and transport moisture and nutrients up the tree,and photosyntate or food material from the leaves to the roots.This food material is stored in the root cells to be used to fuel tree growth. As a tree ages a point is reached where the leaves produce more photosyntate than the tree uses in growing and living. The excess food material is stored in the roots until these fill up then starting low on the trunk the excess is transported from the very narrow one-eighth inch or so of tissue just under the bark to the center of the trunk by a specially developed cell structure called STORRIED RAY CELLS. These cells run at 90 degree angles from those going up and down the tree, and are full of photosyntate food material which is nothing more than one of the sugars like we use in our coffee! It is this stored sugar food material which produces the different color variation expressed as stripe or curl or fiddleback or whatever we want to call it :thumbsup:.
That's what I remember....sorry to be such a :yakyak: :yakyak: but thought someone might be interested.