Some woods are far more easily carved when wet/fresh. Alder (Alnus sp.) is the best example form the Pacific Northwest. It's often used for bowls, masks and utensils. But the stuff goes from cheese to bone when it dries. Smokewood of choice for salmon. I haven't found a similar change in carving texture in local birch (Betula papyrifera), I did approx 70 spoons and 30 forks. The wood had been stacked and stickered, air-dried for years.
Drying time: Bugs like the cambium layer just beneath the bark. Good plan to strip that off. Rule of thumb for air-drying, outdoors and under cover (not cooked in a closed shed) is about 1" per year. Drying from all sides, a 2" stick might dry down to a Moisture Content of 10 - 14% in 12 - 18 months.
There's a rustic furniture shop down my street in which everything is built from diamond willow. Right now, they are brushing out a track into a new harvesting area. The sap should start running and the bark should strip easily in about 3 weeks (mid-May). They will harvest and haul 5-6 cords of wood back to the shop, strip the bark and stand it in a bin labelled 2019. Anything built this summer comes from the 2011 bin.
