Soil Health

Discussion in 'Organic Lawn Care' started by phasthound, May 27, 2012.

  1. Duekster

    Duekster LawnSite Fanatic
    from DFW, TX
    Posts: 7,961

  2. Duekster

    Duekster LawnSite Fanatic
    from DFW, TX
    Posts: 7,961

    http://organiclifestyles.tamu.edu/soil/microbeindex.html


    Unfortunately,most home track builders strip way the top soil and sell it. They do not use a soil mix either so there in our area most lawns are set on hard pan clay.
     
  3. Smallaxe

    Smallaxe LawnSite Fanatic
    Posts: 10,080

    Thanks for posting the relevant paragragh for review, as I'm heading out the door soon...

    I too wonder about the bringing in a microherd to an area, since the microherd that is there already thrives for a reason... I like what the article says about: "The best thing that you can do to “manage” the soil microbes under your care is to grow a healthy stand of turf and pay close attention to the condition of the soil or root zone supporting it."

    Looking into the soil and observing the conditions around the roots will tell me more in a minute than all the reading of symptoms in research papers...
    The real question is in regards to that paragragh is: What is the best management practice of the tur?f??
     
  4. Skipster

    Skipster LawnSite Bronze Member
    Posts: 1,074

    Essentially, what Dr. Zuberer (and all the scientific literature) shows is that the concept of "building soil health" is unfounded nonsense! All the scientific literature tells us that soil microbial populations are naturally robust, but even inhospitable environments can be made more hospitable by doing what is necessary to grow a healthy turf. I understand the mycorrhizae crowd, but mycorrhizae are already in the soil, so adding more is of little benefit.

    It all goes back to the basics of growing plants -- the right nutrients in the right amounts at the right time.

    If you can show me any scientific literature that refutes Dr. Zuberer's results and the results of those whom he referenced, please post it here.
     
  5. Duekster

    Duekster LawnSite Fanatic
    from DFW, TX
    Posts: 7,961

    I have seen the response to Mycorrhizae in urban landscapes.
    Yes, it is present in abundance in old growth forest. If you have a transplanted tree or trees suffering from drought or damage the Mycor does help.

    Again, many of the track homes built around here are in old farm locations and the top soil is completely stripped away. It is a great idea to stock pile it and reuse it but that seldom happens in track home development. So unfortunately we are often stuck with trying to develop subsoils for Turf.
     
  6. Skipster

    Skipster LawnSite Bronze Member
    Posts: 1,074

    I entirely understand the challenges of maintaining turf for new home construction. However, as Dr. Zuberer points out, microbial populations in harsh soils (even such unhospitable soils as kiln-dried sands) reach similar numbers after just a couple of weeks of plant growth (grass or otherwise). So, the compacted and nutrient devoid subsoils some of our customers have are NOT deficient in soil microbial populations and adding the things "soil health" advocates tout will NOT improve soil microbial function. This has been backed by numerous scientific studies. If you can find studies that say otherwise, please post them. Similarly, not one single study has shown that added mycorrhizae colonize plants. If any colonization has taken place, only the mycorrhizae that were already in place will colonize plants. Foreign or added mycorrhizae have never been observed to colonize plants when added to non-greenhouse situations.

    Often, lawns grown in subsoils will perform better with conventional management, like core aeration and proper fertility.
     
  7. Duekster

    Duekster LawnSite Fanatic
    from DFW, TX
    Posts: 7,961

    Really, how would you prove otherwise in the field? Kind of like coughing in the hospital. What has been show is Mycor does not move far in the soil so injection or colonizing the seedling helps a lot to speed up the process. I thought I did post some links.
     
  8. phasthound

    phasthound LawnSite Platinum Member
    Posts: 4,576

    Dr. Zuberer's article is very informative and provides some very good advice. I agree with much of it. I do have an issue with his methodology of culturing microbes in the lab as sound evidence of soil microbe populations.

    Most organisms in the soil are “viable but not culturable,” meaning that we don’t know how to grow 99% of the species on the planet!
    http://www.cfwep.org/education/smsp/module03/m0312-content-colonies.html

    Beginning in the 1990s, the application of molecular ecological methods, especially those based on surveys of genes after PCR amplification, has allowed cultivation-independent investigations of the microbial communities of soils to be made. The power of these methods has largely rendered obsolete the plate count approach to detecting and enumerating subsets of soil bacteria,
    http://aem.asm.org/content/72/3/1719
     
  9. phasthound

    phasthound LawnSite Platinum Member
    Posts: 4,576

    I think the United States Department of Agriculture Natural Resources Conservation Service is a credible source with at least some science background. The article is not an opinion piece and was written for the public. Yes it should have cited sources, that doesn't mean they don't exist.

    The scientific body of soil microbiology has been growing rapidly in the last 20 years. There is much to learn. What was considered scientific fact in many areas of science 20 years ago has fallen by the wayside.
     
  10. Skipster

    Skipster LawnSite Bronze Member
    Posts: 1,074

    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.
     

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