Yes to add to the the wood chips thing. They are great if used in the correct manner and above the surface. When mixed in they cause problems.
A lot of poeple have great luck with a huge wood chip mulch but with no tilling. Some have found that with no tilling it is good but after being mixed in the nitro loss begins and crops do worse. So be careful, wood chips being very high carbon take alot of nitro to brak down and a long time at that.