A germ of an idea

This post is all thanks to Metan over at Buried Words and Bushwa, who commented on my Happiness and Doom post that as well as having a ‘Worm of doubt’ in my teaching tools, I should have a ‘Germ of an idea’. So, here is my prototype:


Crochet bacterium

He’s a sort of generic bacterium, such as you find in diagrams in microbiology text books (here, for example) with a flagellum (tail) and pili (hairs).

Two lovely friends (thank you Sarah and Kate) have offered to send me some eyelash/fur wool so that I can have a go at making Escherichia coli (like these) , which seem to have three of four flagelli and much finer pili than I have managed, and cholera , which appear to have pili on their flagelli.

I’m thinking I could make a whole compost-heap of micro-organisms!

Just tell me if you think this is becoming an unhealthy obsession…

Soil – getting to the root of things

Unless you are practicing an unconventional system of cultivation like hydroponics (see this great blog if you are interested in doing so) then soil is the foundation of everything you grow.

Gardeners tend to value their soil – they see what they are taking out in terms of crops and try to put something back – often by adding compost, soil improvers or fertilizers. My favourite addition to the soil is compost because it doesn’t cost me anything – I am converting what others would regard as waste (from the kitchen, garden or chickens) into a useful resource. I don’t tend to use commercial fertilizers or feeds, relying on compost, woody material from the willow hedge and other prunings, and worm wee. That’s not to say that I won’t use commercial fertilizers, I’m just too mean to buy them! I received a free gift of some organic liquid tomato feed earlier in the year and so I have recently been using this on potted crops – although it does make the greenhouse smell like someone has been storing fish in there for a week!

Unlike gardeners, many large-scale agricultural enterprises don’t use their ‘waste’ outputs as a resource, choosing instead to treat organic matter as rubbish and buy in fertility in the form of fertilisers derived from the petrochemical industry. In a recent post, Yambean highlighted the shocking waste when Spanish farmers dumped cucumbers in protest at being paid so little for them by the supermarkets. I asked her about this and commented that they would, surely, have been better composting them and returning them to the soil, but she tells me that composting is unheard of in that part of southern Spain and the soil is, as a result, completely impoverished. It’s shocking to me.

Soil is a complex system consisting of a mineral component, organic matter in various states of decomposition (from freshly fallen leaves and recently deceased animals to humus and root exudates) and living organisms (bacteria, fungi, worms, insects, other invertebrates, plant roots etc). It is common sense that we need to nurture such systems if we wish to make use of them. Unless we replenish the soil, it will not continue to be productive. This was the basis of the organic movement in the UK, you know? Ever wondered why the Soil Association (one of the regulators of organic produce here) is called the Soil Association? Well, it was founded in 1946, partly because of concerns about “the loss of soil through erosion and depletion”. In 1967, the association stated that “The use of, or abstinence from, any particular practice should be judged by its effect on the well-being of the micro-organic life of the soil, on which the health of the consumer ultimately depends.” So, you can see that their name really does reflect an acknowledgement of the key importance of the soil.

In large-scale systems, particularly where it is common to have periods when the soil has no vegetation cover, erosion is common. As the Soil Association noted in 1946, soil is not simply lost as a result of nutrients being extracted because we grow crops in it, erosion is also a problem. If you live beside the sea (as I do) you cannot help but notice the brown water around river mouths after heavy rain… this is the soil that was previously supporting plants. It does get replenished naturally – rocks weather and add to the mineral component, organisms die, excrete and shed parts of their bodies and add to the organic matter – but bare land is subject to high levels of erosion that can take a significant time to be replaced. Thus we lose substrate, nutrients and water-holding capacity because we chose to leave soil bare – a simple ‘green manure’ such as clover could reduce the erosion and enhance fertility (clover fixes nitrogen).

If we do not care for our soil is it any wonder that there is an increasing need to add to it from external sources and rely on non-renewable resources? Many people, when thinking of organic growing, focus on the absence of pesticides, herbicides and artificial fertiliser, but I’d like to suggest that one of the most important reasons to support organic production is because its practitioners care for the soil and are, thus, ensuring that it is available for future generations to use too. In my garden, I would like to think that I will leave the soil in a better condition than when I found it… not just preservation, but enhancement.

Very small things

I’m very well read. Possibly not in the sense of great literature – I’ve never read a whole novel by Dickens, my Shakespeare is shaky and I’ve managed the first chapter of Catch 22 about four times but never got any further. However, I work as a scientific editor and this means that I get to read some fascinating pieces of research (as well as some dull ones). And they come from all over the world because, mostly, I work with authors whose first language isn’t English. Much of the work that I read is at the cutting edge of its particular subject, whether that’s ecology, genetics, forestry, biotechnology, nursing or education, so I get to know about new ideas and technologies before they have even been published and become available to the rest of the world… which is how, a couple of years ago, I came to know about research in Sweden looking at how micro-organisms that occur naturally in the soil can be used to deal with pollutants from the paper industry… and not just make them harmless, but convert them into a useful product… biomass or ethanol to use as fuel, for example.

Which brings me to the point of this post… aren’t micro-organisms brilliant?

Yes, I know some of them cause diseases, but they are in the minority. Go out into a woodland and scrape the top layer of leaves off the soil and you will find very fine white strands – fungal mycelia. These make connections with plant roots, providing the plants with improved access to water and minerals. And the only time most people are aware of them is when they produce their fruiting bodies – mushrooms and toadstools. But these fungi are not really micro-organisms – we can see them with the naked eye (at least some of the time). What about organisms that are even smaller?

Bacteria and small fungi in the soil are essential components of the system – without them the soil simply would not function in the way it does. They are responsible for all sorts of activities, but especially decomposition of plant material, dead animals and faeces… without this happening the world could not function. There are also special bacteria that fix nitrogen from the atmosphere and without them there would be no life as we know it since nitrogen is an essential part of the proteins that are building blocks for life and enzymes that allow all sorts of chemical reactions to take place inside living things.

We use fungi directly in our food chain – mushrooms and truffles are an obvious food, but there’s also the yeast we use in our bread, beer and wine, and to make Marmite and various cheeses. Remember too that the first antibiotic, penicillin, came from a fungus. We eat bacteria as well, although that may not be quite so obvious, but they are used to make yoghurt, cheeses, wine, vinegar, soy sauce and various pickles.

Algae are also interesting – they are microscopic (or bigger) plants. They are very simple in terms of their structure, but they photosynthesise and so they, like all green plants, make their own food from water and carbon dioxide with the help of sunshine. As humans, we don’t tend to eat much algae… although we could… but lots of organisms do. If you head over to the Aquaponic Family blog you will find out all sorts of interesting stuff about algae and what they can be used to do.

So, we really should appreciate the micro-organisms around us more. If we are gardeners, we can care for the fungi, algae and bacteria in the soils that we cultivate by ensuring good soil structure and plenty of compost for those decomposers to work on. Be thoughtful, too, about what chemicals you apply to your soil – changing the pH will change the composition of micro-organisms, applying fungicides may kill the fungi you do want as well as those you don’t. Allowing the soil to become waterlogged will deprive decomposers of oxygen and dead matter will not break down fully (that’s how peat forms). Our compost heaps also rely on the action of micro-organisms, creating a valuable resource for the garden in the form of compost, but also generating heat which, if we are careful, we can make use of by means of hot beds or siting our composter against the greenhouse or inside a polytunnel. You can even grow squashes on top of your compost heap for an early and abundant crop.

So, next time you’re sitting enjoying a beer or some wine and cheese, give a thought to the little critters that made them possible.

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