[David Marek]

Neat article. I did not really know what all of those bacteria do, or that like mycorrhizae and the rhizobium, they also colonize the plant. Several of them- including pseudomonas and baccilus are added to Plant Tone (and I think also the new Tomato Tone) which is the main reason I buy it (I could care less about the feather meal- a friend has plenty of chicken and horse poo). I like to think that it helps to keep the plants a step ahead of the pests. Others, Plantshield and Rootshield are different strains of Trichoderma harzianum, are specific to reducing the ability of pythium, etc to establish itself.

I am guessing they must be isolated and grown on sterile media before they are blended and added to a carrier in a product available to us gardeners/ growers/ farmers, which would explain the cost $$$. Hopefully, spreading compost is a close second. Or compost tea.