Soil & Underwear @ Russborough by Mark Keane

In the interests of Science, at RHSI Russborough over the last few months, we have been burying underwear! Let that sink in a bit before reading on…

The consensus view amongst the volunteers is that there is something deeply funny about burying pristine, white, men’s underwear and then returning several weeks later to see the damage done!

Technically, this is called the Underwear Decomposition Test, colloquially the “The Pants Test”, and is designed to assess the levels of microbial activity and the small-beastie population in your soil. So, a 100% cotton brief is interred and its degree of degradation over 8 weeks is used as an indicator of your soil’s health (see A). In short(s), if the brief is a lot briefer over time then biological activity is higher and your soil is healthy (see B and C).

In June, we signed up with several hundred other groups — schools, farms and gardeners — to take part in this citizen science project, called GroundTruth, which was organized by Teagasc. The project involved carrying out four different soil-health experiments between June and September: the aforesaid Pants Test, a timed-count of insects in stands of native flowers (called a FIT Count), an earthworm count and the GrassVESS Test (designed to assess soil structure). All of these tests are directed towards assessing the soil biodiversity and soil health of selected sites across the country, to gain some insight into what’s actually happening, literally on the ground.

We chose 5 different sites in the walled garden for these tests: two in grassed areas and three in different flower beds. So, in mid-July, our Dunnes-best men’s cottons were buried, before being lifted 8 weeks later. The results were quite interesting. In general, the grassed areas had poorer soil health than the herbaceous borders (compare C and B). In part this probably occurs because the latter are mulched, dug and fertilised more than the grassy areas; though some of our long-standing volunteers suggested that it might also be due to hidden paths beneath the grass, that crossed many areas in the old garden. Also, surprisingly, some flower beds were much better than others; the circular wild-flower bed (near the tool sheds) and the cottage garden in the NNE corner of the garden (by the collapsed peach house) were much healthier than the East border area used this year for cut flowers. The most likely explanation for these differences seems to be extended use. The latter section was only given a light dig over having been cleared of irises, but not of persistent scutch grass. However, this does not explain why the wild-flower area is so good, it tends to be left to its own devices; it could be doing better because of the biodiversity in the plants growing there and its no-dig status.

Sadly, one of our pants went missing. The second grass-area burial, in the south end of the garden, was never found because the edges nearby were mowed, making it hard to identify where the cotton-skeleton lay. Perhaps future archaeologists will find it and wonder whether it was a ritual offering to the Garden Gods!

Mark Keane