This is a fun experiment you can try with your own pastures and fields. It comes to us from Anthony Bly and Sara Berg of South Dakota State University Extension. Just remember that different areas will have different kinds of soils and you may get different results.
Soil microorganisms require carbon to survive. Men’s cotton underwear briefs contain high amounts of carbon. Therefore, briefs can be buried in the soil and retrieved later to see and evaluate soil microbiological activity and ultimately, soil health status. During the South Dakota Soil Health Coalition’s first Soil Health School in the Aberdeen and Ipswich areas, a “Tighty Whities” demonstration was conducted. The briefs were buried to about the waistline in the soil five weeks ahead of the school at 3 sites that included: corn with conventional tillage, soybeans under mulch tillage, and no-till soil currently with growing cover crops. Soil health school participants had the opportunity to extract the briefs and view the results of five replicates in each field. Results were revealing…to say the least.
A new brief was compared to one brief from each field.
The first soiled brief in the picture above (second from the left) was from the no-till field with cover crops. Hardly anything remained of the brief, indicating extensive soil microbiological activity. The brief from the mulch (reduced) tillage soybean field (third from the left) had more material remaining when compared with the no-till/cover cropped soil, and the conventional tilled corn (for right) had the most material which indicated the least soil microbial activity. All 5 briefs buried at each site were weighed, with the results matching the degradation observed in the photo (Table 1).
Kathy’s Note: If the lower case letters and some of the other data is as confusing to you as it sometimes is to me, here’s a translation: “Significance” is derived from statistics to help us see if a practice really makes a difference. The difference is something that you can see, that you can acknowledge and that you can expect again (under the same conditions). Probability (PR>F in the table above) indicates how certain you are that you’ll get this same result again. So what the statistics here show us is that there was a significant difference seen, and after 5 replications (5 pairs of underwear buried in each field) the chances that you won’t get these same results are 1 in 1,000.
The “Bottom” Line
Soil microbial activity is a key soil health indicator. Most seasoned soil health producers recognize the value of the soil microbial kingdom and often refer to it as “the herd.”
If you’re a crop producer considering no-till and are concerned about too much residue consider using another herd to help your soil microbial herd. Integrating cover crops and livestock in a no-till system can profitably utilize and manage plant residue levels.
This is great. I’m sending Anthony Bly and Sarah Berg Hotter Spotter ribbons for their outstanding study. I must replicate this experiment!
Hi Kathy
I saw this “tighty whitey” demonstration at a soil health event earlier this year.
I would like to include this in one of my pasture tours.
Do you know the depth in the soil that the undies get placed at?
I the information you make available, keep up the great work!
You don’t have to bury them deep at all. These were buried up to the waist band. Here’s a video of a fellow digging the hole for the test: https://youtu.be/Ym0naU1oQmY?t=1m3s
I’ve just been reading about the importance of carbon for soil health. This article just confirmed this necessity. A picture is worth a thousand words. Thanks Kathy
P.S. My website will be live around December 10th
Kathy – this is a wonderful article. Can I have permission to use the photo and tell the story on my blog GardenMyths.com? Full credit and a link to this page will be given.
Hi Robert. Thanks! Yes, please feel free to share. 🙂
They were buried horizontally at a couple of inches deep.