A few weeks ago I posted on the disappointing inclusion of compost tea in the APLD’s Guide to Sustainable Soils. Included in my discussion of the issue was the suggestion that people involved in writing the guide also benefited financially from compost tea applications. This led to some very honest and constructive emails between me and the APLD’s national leadership, which resulted in educating both parties.
Here’s what I found from the APLD’s President Susan Olinger and Sustainability Chair Toni Bailey: “As members of the Board of Directors of APLD, we can verify that there was no financial motive behind the inclusion of compost tea by the volunteers that wrote the soils guide.” This is heartening and makes me feel less cynical about the motives behind including compost tea in the publication.
And here’s what I was able to impart to the leadership of APLD: that while landscape designers may like to include compost tea as a soil amendment, the belief in its efficacy in improving soil tilth or biology is not supported by legitimate science. It’s not a matter of sides, or opinions, but a matter of scientific evidence.
If the APLD doesn’t intend its guide to be a scientifically supported document, that’s certainly fine; landscape designers aren’t scientists, after all. But since good soil science-based information is found throughout most of the guide, the inclusion of compost tea and mycorrhizal inoculants could easily be interpreted by others as science-based as well.