Great to have such a positive response to BD. I've replied to posters
separately but for others who may have the same queries - first I'm a
journalist/researcher closely involved with one of the farms in the
Reganold study. I'm no farmer but I'm pretty close to the action with
plenty of mud and cows--t on my boots, not to mention hundreds if not
thousands of planted trees to my credit.
More to the point - how do we know the BD preps make the difference.
In pure scientific terms of course we don't and as one poster pointed
out it would make an excellent subject for a research programme. Some
work was done by Pfeiffer in the US who worked with composts identical
in every way except for use or non-use of individual BD preps. The
ones with the preps were shown to enhance presence and activity of
particular organisms. I can find the exact reference for anyone who is
interested. Also forgive my lack of precise scientific terminology!
In the Reganold study, which I don't have to hand at the moment, farms
included dairy, cropping, mixed (livestock & crops) and some vegetable
growing. Taking a pasture situation - with which I'm most familiar -
the inputs from rotation/legumes/raw animal manure would have been
common to both BD and chemical farms. We don't spread composted
manure on our pastures. The differing inputs were the NPK fertilisers
on the chemical farm as opposed to the herbal preps and fish
fertiliser foliar feed (made with preps) on the BD farm. It would
seem reasonable that all other things being more or less equal a
starting point for research into soil microbe indicators would be the
One poster, Woody, made the point that he 'would expect microbial
respiration to be a product of the whole management program in general
and the high organic matter in particular'. Good point and the whole
management program is vital. But in our case in particular the sandy
soils on which the pasture is based do not naturally contain or
receive a high rate of organic matter.