Humus Part 1: Not Dirty, Hairy!

The Difference between Dirt and Soil has to do with this amazing word: Humus.

I love humus. I do. I spend time contemplating how it works, what it is about and how it affects everything that we do in soil management. So in my small brain, any discussion about what soils are and are not has to start (and end) with some kind of thought as to what does and does not happen to the Humus content in the soil.

Most of us will agree that soil is perhaps the most major natural resource that we are involved with. Yet most of the same people who acknowledge this simple statement are quick to move right past the velvet ropes of carbon based life and get right into the chemical salt dance club. You can blame the hot fertilizer chicks or the mean agronomy bouncers, but the truth is, the good party is in the Humus kitchen and it is still pretty underground. Ignore the Velvet Underground of Humus and you risk joining other failed soil disaster cultures like Mayans and Mesopotamians.

The soil dance floor moves with life in a natural light show of Oxygen, Water, Minerals, and Decomposing Plant and Animal Matter. It’s actually simple to fit in with the groove and when those elements combine they create ongoing party life if not disturbed. Healthy soil just works, nutrients are available to the plant and everyone Wang Chungs. As Turfheads, we see this in the quality of the playing surface, not just the color of the grass, but in the overall quality of the turfgrass sward.

It’s a simple drink recipe. Good soil consists of 93% mineral and 7% bio-organic substance. The Bio-organic blend is right at about 85% humus, 10% roots and 5% living organisms. The “live” world consists of microbes, fungi, bacteria, earthworms, micro and macro fauna.

…and the Turfhead’s old Outlaw Buddy, Rhizoctonia, who we need at the gig for security, but like Hell’s Angels, can create total chaos…

Surrounding the club is Carbon Dioxide.

During the growing season, plants party with the CO2 in a much better way than a Deadhead with a Nitrous Tank. Plants fix the Carbon Dioxide by the Miracle Ticket called Photosynthesis. About 10-25% of this fixed Carbon finds its way back into the show after being treated at the Oxygen tent. It gets back to the soil through the roots in the form of Root Exudates, something on the order of shake or trimmings.This happens even if all the plant residues are eventually removed.

Fungi and Actinobacteria seem to be the best jazz players around at Humus formation. The end product of their microbial degradation results in Humus. The cats that play have heavy names like Aspergillus (a moldy cousin to Dobie Gillis), Pisolithus (who used to sell shrooms to Keith Richards), Streptomycetes (gram-positive mosh pit bacteria) and the Turfhead’s old Outlaw Buddy, Rhizoctonia, who we need at the gig for security, but like Hell’s Angels, can create total chaos if left to do their own thing.

Over the years, the the Techo types (aka, Science) have tried and tried and failed and failed again to create Humus. It can’t be done synthetically. Can’t. It’s life and it’s delicate. Like a computer being fed every note of a Jimmy Page solo or a Keith Moon rhythm, the recipe is known, but it takes nature’s talent to make it happen. However, the whole concept of stewardship means that humans can influence and control the whole process by virtue of what is input and what is not. Too much salt fertilizer, too much organic addition, too much control agents and the system breaks down. Too little, and often the same thing happens. That balance can be assessed in the fertility and productivity of soil. It’s that simple.

It’s called Stewardship and that word along with fellow band mates Organic and Sustainable have caused a ton of good and a great deal of chaos. Why? Because they were never supposed to out perform and upstage Mick Jagger–the Humus, the true frontman.

5 Responses to “Humus Part 1: Not Dirty, Hairy!”

  • Scott McBeath:

    Dave- I have been quietly laying in the weeds reading and following the blogs of a few, minding my own business and trying to keep up with the careers old friends. After reading Humus: Part I today, I have to say my pea brain got more of it today than it has in the past 20 years. Maybe it was Dobbie Gillis or the reference to Keith Richards, but it really made alot more sense today than ever. This was easily my favorite article blog or otherwise. Thank you,
    Wet in PacNoWest,

  • bruce nelson:

    You’re probably going to compose the second movement of your soil rock opera around some methods to keep these soil component musicians in balance so no one is upstaged or drowned out. I’m looking forward to some methodology to appraise the sweet sound, smell and groove of well functioning, sustainable soil.
    “Gotta’ have more cowbell man!”
    Cold in the Rocky Mountains,

  • Dave Wilber:

    Scott, Thank you sir. Coming from you…a nice compliment. Although I think the clear air helps.

    Bruce, Thank you as well. Cowbell references are always the best.

  • rich coyne:

    Dave, great read ( typical Wilber) Hope all is good. Rich

  • was looking forward to humus 2 but thought i would re-read one first. well done and yet again the lyrics ‘what a long strange trip it’s been’ come to mind. thanks to jazzing up the world of soil


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