In terms of Kyoto it would be considered carbon neutral,
Whereas, if you take coal out of the ground and burn it, you are adding a net gain of carbon to the atmosphere.
So as you increase carbon dioxide, plant growth is actually boosted,
As the plant grows it is drawing carbon dioxide out of the air. When you burn it you put that carbon dioxide back, so the net effect on atmospheric CO2 is zero.
As the plant grows it is drawing carbon dioxide out of the air,