stacking and regular soaking with pee (horse or human) will help to rot it down, plants require the Nitrogen/Carbon ratio th be about 1 - 7 straw is approx 1 - 70 wood is higher. Nitrogen is a mobile element, and will escape to the air, keep covered to increase rate of decomposition.
the nitrogen robbery sketch usually occurs when too much carbon is dug in to the soil, the soil nitrogen is used to decompose the carbon, not to feed your plants. this is not so much of a problem if used as a surface mulch instead of digging in. rgds, tony ;)