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Re: soil microbes
I have a hard time with the generalities in Dale's (nosliwelad@YAHOO.COM) post.
Let me give you some data, something I'm much more comfortable with than the suppositions that some people have about what is or is not present in ag soils.
When we assay healthy soils from native grasslands, or assay agricultural soils that don't need pesticides or fertilizers, we see 600 million or more bacteria per gram of soil.
Ag fields treated with high levels of pesticides, fertilizers, etc, we only see 1 million bacteria OR LESS per gram.
Maybe, just maybe, an inoculum of the missing beneficial critters would be a good idea.
Healthy soil - as defined for example, by very little disease, few weeds, low requirement for fertilizer - has 150 to 300 micrograms of a good mix of fungal species. If soil only has say 5 to 10 micrograms of fungal biomass, based on the testing we've done with corn, wheat, potato, etc, then disease is significant or fungicides, insecticides and nematicides are needed, herbicides are needed, and fertilizers are required.
So, let's not make generalities about agricultural soils, ok? Some fields have good biology, some don't. Don't make statements that do not differentiate healthy soil from not-healthy.
Inoculation of beneficials into soils lacking beneficial organisms clearly improve bio-control.
Inoculation of soils that already have beneficial species doesn't necessarily help. Also, if the foods those "bio-control" organisms need to eat are not present, no amount of addition of individuals is going to help. For example, think about dropping people into the middle of the Sahara, with no food or water. Not going to build a city, no matter how many individuals you drop in.
In a great deal of our agricultural soils, we have "blown off" the foods for those organisms. If the organic matter of the soil is less than 1%, the foods to feed the beneficial, bio-control organisms just aren't there.
So you have to add the organisms AND the foods to feed them. You have to re-establish the habitat for the organisms to return and do their jobs, as Joel Gruver said.
So, if in the past you have added beneficial, bio-control organisms to soil, and did not check to see if they were there already, or if you did not add foods to feed those beneficial organisms, and did nothing to make sure their habitat was appropriate, then there may be a perfectly reasonable explanation for why they did not perform as you expected.
Some pre-testing to determine the soil's condition before adding some set of organisms is needed.
Elaine Ingham
President, Soil Foodweb Inc.
www.soilfoodweb.com