Why would it make a good carbon sink? Animal will eat and which producd co2
You're thinking too small OP. You need to pitch this idea in Brazil and the Congo. Instead of burning the rainforests to clear farmland they should cut all the trees down and bury them to sequester the carbon.
Out in the country (ie small town in the Midwest) many recycle their trees by tossing them in a lake as a fish habitat. That being said, a lot of communities recycle them by putting them in a wood chipper then selling it for a nominal fee that goes to a charity.