[bluGill]

No, because water in all dead material will dry out and then lightening strikes will start a fire and turn it all into CO2 again.

If you want to make a difference make sure that you start a forest and grassland fire every single year - the regular fires ensure the resulting fires are small and leave a lot of carbon behind some of which will get incorporated into the forest floor and forever stored away. Plus forests depend on those fires to clean up all the under brush.

Note, the above applies to most forests in North America, but you need to check with a local expert in forests to understand the details and where it doesn't apply. Every location/climate has different forests with different needs. There is no blanket statement that is right for everything.