[imported_Eru]

Here's what I understand of the log system and the scripters can correct me if I'm wrong:

Recommended skill level for getting rarer logs is 100.0 (GM).
You can get these logs at lower skill levels, but the chance is extremely small.
You can get any type of log from any tree.
You can use any type of log to craft anything in the carpentry menu.
Only certain items receive new colors. (Containers, Furniture, and wooden shields).
Items that do not receive color function normally. (weapons, parts, etc.)
Razor treats colored logs the same as non-colored ones.

In order to craft with colored logs, you select the type of log to use from the bottom left-hand corner of the AoS crafting window, much like when you choose the ingot type for smithing.