Soil has been on my mind quite a lot recently… mainly because there’s a bare bed in the garden since Mr Snail of Happiness harvested kilos and kilos of potatoes on Saturday afternoon. The potatoes are safely in boxes in the loft now and the bed is awaiting some pleasant weather so I can get out there and plant something in it. I quite like the look of bare soil, but it’s not an ideal system… it’s available for all sorts of seeds to colonise, it can get washed or blown away, and in my small growing space it seems like a waste of a resource.
If I leave this soil, it won’t stay bare for long
In fact, the only reason my soil is bare is because it poured with rain yesterday, so I was not encouraged to go and plant it up. I could seed it with a green manure, but I have other plans for it. I have some red onion sets (variety Electra) waiting to go in one end of it, plus several varieties of oriental vegetables to go in the other end. Earlier in the year I tried inter-planting onions and oriental greens, but the latter were too successful and swamped the onions… I will not make the same mistake again.
Given the presence of all this bare soil, I was interested to read this post on Australian almond orchards (I’ve only recently discovered the blog, and I really like it), in which the soil below the trees is kept completely bare, thus supporting no pollinators so that the farmers have to bring in bee hives to ensure pollination. The energy required to maintain this system must be huge, and makes no sense in terms of sustainable production.
The idea that keeping soil bare artificially over a long period of time is a good thing, seems very strange to me. Whilst in nature you do see bare soil, it is always only temporary, and something always comes along to colonise it pretty quickly. Even when a site is severely contaminated, some species can survive. My first job as an ecologist involved surveying old metal mines in mid-Wales. Many of the spoil heaps appeared quite bare from a distance but, close up, even the most toxic spoil (contaminated with lead, cadmium, arsenic, copper and other heavy metals) had a flora of lichens and even grasses (such as sheep’s fescue). And more than 20 years on, I return to some of the sites and they are supporting heathland, grassland and even trees.
The spoil heaps at Cwm Rheidol in 1982
The same spoil heaps 20 years later
Since, as Ian Malcolm says in Jurassic Park, “…life will not be contained. Life breaks free, it expands to new territories” I think I want to control what’s growing in my raised beds, so I’m off to plant those vegetables now!
Ann Owen
/ September 17, 2013Would you know, perchance, what the reasoning was behind keeping the soil in the almond orchards bare? Just interested.
LikeLike
The Snail of Happiness
/ September 17, 2013Well, according to the person who wrote the original post: In Australia, some growers do it because there is government extension material from a few decades back that advise growers to get rid of ground cover because it increases frost damage and competes for soil moisture with almond trees. I’m not sure how though, as the trees are deep-rooted and most grasses and wildflowers are shallow-rooted…but I’m not a soil scientist. Also, it’s apparently a pain during harvesting – because the nuts are shaken off the trees onto the ground where they need to dry, and grass doesn’t let them dry.
LikeLike
Ann Owen
/ September 17, 2013Thanks Jan, I’m not soil scientist either, but the practise doesn’t make sense to me. Surely a layer of turf allows the soil to hold more moisture in the first place, not to mention provide a home for all those beneficial soil micro organisms.
I suppose it’s a good example of the prevalent strange, cut off, mechanistic view of nature.
LikeLike
The Snail of Happiness
/ September 17, 2013I wonder if it’s an extrapolation of the fact that coarse grasses do compete for water with establishing saplings. To counter this, we often mulch around newly planted trees, but once they get bigger and their root system develops it’s simply not necessary.
In my opinion, a diverse ground flora is much more likely to support diverse soil flora and fauna, prevent erosion, increase organic matter content and maintain soil structure, as well as supporting pollinators, as the author found.
I have found that human beings tend to oversimplify… looking at systems as a series of isolated compartments rather than a complex and interacting set of processes… I suspect this is the case with the bare soil paradigm… no consideration of even slightly broader implications!
LikeLike