Taxodium spp, Cupressus spp. and Chamaecyparis spp. all of the family Cupressaceae
Cypress is one of those woods that was logged enough, and floated on rivers enough, that modern wood reclaimers have salvaged many sunken logs that are from 50 to more than 100 years old. These are called "sinker" cypress or "deadhead" cypress and those terms do not refer to any SPECIES of cypress, but to ANY species of cypress that has sunk in a river and been salvaged. It can be some very pretty stuff.