Originally Posted by Skipster
phasthound, if many of the microbes are not culturable, then there must necessarily be more in the soil than the millions of species per gram that we can already identify. Thus, adding more microbes or adding sugars or carbon to the soil could only move the needle a microscopic amount. This has been proven in the research. Your links do nothing to disprove this.
Sure, our understanding of soil microbiology can change, but if you read the current 2011 and 2012 literature, you'll find that the conclusions are the same as Zuberer's. You're also overlookign the obvious differences between annual and perennial crops and legume production vs. non-legume production. What works best for crops (as the USDA article was written for) is not always best for lawns. For example, a lawn with as much organic matter as is recommended for wheat production would be thatchy, spongy, and full of moss and disease.
You can keep using microbial snake oils if you like -- I certainly am not here to tel what you can or can't do. Many people fall for the fertilizer parts of those products. They get so excited thinking that the microbes or sugars worked, when in reality, all you're seeing is the N and Fe those products also have. You could have applied N and Fe yourself, and gotten the same results for a much lower price.
Bottom line, all the scientific research for soil microbes in turf (from 1950 to 2012) tells us that soil microbes are ubiquitous in the environment and there is little we can do to negatively influence their populations. The research also tells us that the best thnig we can do for microbial populations is to manage a healthy stand of turf.
Over the last 60 years, no scientific evidence has disproven that. I'm certainly not going to throw my money behind something that 60 years of science says doesn't work.
The products I look at have pretty low N and not enough to elicite the responce seen. Even if the product were 100% N and Fe the application at 8# per AC would not give the responce alone.
As a matter of fact there is little we can do to significantly change the soil hence the reason we have to keep applying fertilizers of any type to turf. Granted, a little bit of sugar and colonizing with microbes there is little chance they will thrive in poor soils. The Carbon / Nitrogen cycles and the impact on plants and bacteria is pretty complex and never in a steady enviroment.
In an old forest we have leaves fall, and continually decomposing over centuries.... in turf we rake up the leaves and often take away the grass clippings.