From what I understand, freshly cut wood is fine, it's just going to take longer for you to get the "payoff". A combination, of both, fresh cut and rotting wood would be the ideal situation. Rotting wood would serve you in the near future, while fresh cut would pay back in the years to come. We put all of our fresh cut towards the bottom of the pile and kept the "rotting" wood towards the top. This way we will be able to use the decomposed wood much more sooner then the fresh cuts on the bottom... which will be used years down the line.
