From Valerie@stuart.ak.planet.co.nzMon Feb 27 13:47:07 1995 Date: Tue, 28 Feb 95 07:10:36 +1200 From: Valerie Cowperthwaite To: sanet-mg@ces.ncsu.edu Subject: Biodynamics/soil microbes 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 preparations. 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. With