Since joining ecoartspace last year, I have been monitoring the Soil Dialogues group. They were working on a collaborative shroud to be exhibited at a soil conference held in Italy in 2024. Having missed that opportunity, I decided to conduct my own experiment to test the microbial activity of my regenerated soil at Plot 46.
The Cotton Strip Assay is a simple and inexpensive test that measures the amount of biological activity as determined by the degree of degradation of a standardized strip of cotton buried in the soil (1). I would test the effect of temperature on biological activity by comparing the relative decomposition of cotton cloth buried at Plot 46 over the winter with soil kept at ambient temperature in my studio.
On October 10, 2024, I buried two 32 X 14 inch pieces of old white sheet at two locations on my plot (Figure 1). I also took a bucket of soil which I put in a large glass apothecary jar. I buried a similar size piece of cotton cloth in it and planted some bean seeds in it to provide root exudates to any living organisms. My Studio Terrarium is pictured in Figure 2. I really enjoyed watching life in the terrarium and I kept my eye on the cloth over the winter. With longer days of spring, I was surprised to see the cotton cloth disappear almost before my eyes.
The snow gradually melted and the frozen ground thawed. On April 24, I went to the farm to exhume . I was able to find one of two cotton cloths. It looked dirty, damp, d was stiff like a crust of bread (Figure 3). I dug around a second marker but found nothing. Then I returned the terrarium soil to the plot (Figure 4). It contained quite a few earthworms that had been living their secret lives away from the glass walls. There was absolutely no sign of the cloth remaining in the soil. I guess with all those hungry worms they just ate it up. Because I could not find one of my two cotton cloths and cannot draw any firm conclusions about the effect of temperature and the microbial activity in the soil.
That evening I spread out the fragile cloth on my glass top table in my home studio. The cloth was so fragile, I realized I would not be able to rinse it, let alone print on it as I had hoped. So I made a video.
The Soil Shroud
Years laying in wait, tossing and turning, washing and drying, a cotton sheet’s repurposed as a drop cloth, cleaning rags, or a shroud.
Not a burial cloth but a buried cloth. A 32 x 14 inch piece of cotton sheet becomes an experiment in microbiology to observe in action the power of the soil biome.
The burial takes place at Plot 46 in mid October 2024. A shallow grave dug, the cotton shroud is laid to rest. The hole refilled, a garden label marks the gravesite.
Winter snows come and go like laundered sheets flapping in the wind.
Spring finally here, the buried cloth is exhumed. Rigour-stiffened, like a piece of stale bread, the earth-crusted clump is retrieved for further examination.
Under laboratory lighting, the congealed bundle is prised open.
Every stuck fibre resisting, the once strong surface is now splitting, threads unravelling, disturbed and disturbing.
Blobs of earth adhering, stained, discoloured, deconstructing; riven with creases, fissures and craters, the surface is ravaged by unseen life.
Biogenic carbon in the cotton cloth is candy for the decomposers — the bacteria and fungi, which in turn are food for other critters in the soil food web.
A few tiny snails, millipedes, and a nematode or two visibly struggle across the now hostile wasteland.
Drying, dying, traces of life extinguishing, the shroud, indeed, becomes a relic.
Reference:
(1) Nachimuthu G, Hundt A, Palmer B, Schwenke GD, Knox OGG. Cotton strip assay detects soil microbial degradation differences among crop rotation and tillage experiments on Vertisols. J Microbiol Methods. 2022 Sep;200:106558. doi: 10.1016/j.mimet.2022.106558. Epub 2022 Aug 14. PMID: 35977630.