We have used only woodash for pH amendment for about 15 years, we did trials in the beginning and it worked effectively in our soils.  We have soil that needs adjustment to grow alfalfa, one of our main crops.

Most of our land has high fertility because we produce and apply manure, I wouldn't expect a very noticeable difference in a woodash strip trial.  I am applying the ash first as a liming agent and secondly to maintain our K levels, also there are a few other nutrients that come along with it. My soil tests are telling me it works.

Our local research station has been conducting long term woodash, manure and commercial fertilizer trials in different combinations, the results tell me I am doing the right thing to use the ash.

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