When they cut wood out of a tree for lumber they run it through a dry kiln to dry the wood. When they cut wood for pallets they are not as fussy with the wood. They just stack it up and let it air dry. Depending on how old the wood is it may not be dry enough to build projects out of. The wood could twist and warp or even crack if it continues to dry further. You would have to have a moisture content meter to really be sure the wood was dry enough to use for projects. If you live in a humid climate the wood should dry to at least 12%. It should be drier in aired climates.I'm not sure what you mean. I can tell that there are some beer looking ones. However there are some that look more weathered. Sorta grey. Is there a type of treatment I could use to season them?
Stack the wood up in a dry place with 3/4"x3/4" sticks between the layers of wood so air can circulate through it. A hot dry place like your attic would be good, just don't put so much up there you overload your framing. I never have liked air dried wood. I bought some red oak 4/4 wood and kept it for three years in the attic of my parents garage and it never did dry enough to use. I finally moved away from home and forgot the wood. Now 40 years later I know it's dry but I never knew when it became usable.If it is not dry enough hw would I go about getting the moisture content lower?