Yes, if you want to "permanently" (i.e. a thousand years at least) sequester carbon from biomass sources you have to burn them to charcoal and bury that.
You can also pump CO2 into deep coal seams, displacing CH4 which is then burned in a closed capture system. The CO2 released from burning the CH4 is also sequestered resulting in a net gain since CO2 preferentially adsorbs to coal at a roughly 3:1 ratio to CH4. Economically viable coal seams are widespread globally, and exist within 50 km of most coal burning power plants in the United States.