Dan, Most of what we learned about oak was learned from those who process it or build things from it. White oak is far superior for artillery carriages for two main reasons. First it's grain is waterproof. Red oak is an open grain wood and water can pass through it.
The way to tell for sure is to look at the large pores in the end grain. If they are open (you might have to use a razor blade and make a clean slice across the end grain surface), it is a red oak. If they are totally plugged up with a white crystalline substance (tyloses), then it is white oak.
If the whiskey distillers used aging barrels made of red oak instead of white oak, most of the liquor would leak out over several days. Now THAT would be a real shame.
Second, white oak is far more resistant to decay than red oak and white oak resists insect attack very well also.
The last time I was at the lumber yard, I asked if anyone spoke Latin and nobody did, so I don't know their Latin, scientific names. Then when I asked if anyone knew any Latin names, all I got was Rodriquez, Hernandez, etc., so I gave up.
George and Richard have already explained 12/4 vs 3" very well, but the real reason they use all of these different forms of measure is money. If you are not a well informed customer, then they make more money. Did you ever buy a car or truck? Enough said!
When Tracy asks for 12/4 I am reasonably sure he wants a dressed full 3 inch.
That's what I want, but what I get is 12/4 rough around here, which will yeild 2.75" if I am really lucky, but more commonly 2.65" or 2.70", AND your cost per board foot is calculated on "rough" lumber, not surfaced lumber or what the final volumetric yield will be.
Moderators, We will be coming through and hope to see
everyone who was at the Floyd shoot last year and we will tell you where we find our thicker white oak carriage lumber. After all, it's not rare, it just takes a long, long time to kiln dry it and the number of months that it's relatively easy to find are few. All this works AGAINST the casual buyer, which is why we are seriously looking now, a full eight months before we absolutely need it. A special thanks to Richard the "Kindhearted" for his help in our quest.
Regards,
Tracy and Mike