7 November 2015

Rootling In The Soil

Like the mycelium in this image I have many hyphae probing for nutrients in the soil of the internet. I mean I'm always on the look out for new places to find new information about the natural world.

A session on Twitter usually begins by following a hyperlink to a newspaper article, then the opening of a new tab to find the author's own webpage, that usually leads to their own blog. In amongst the writing may be a reference to another expert, and then the whole circuit begins again via bursts of Amazon browsing, and the rush to Tescos to get a new printer cartridge to print out that 20 page pdf.

The above photo is of the mycelium (fungus) growing round the roots of a pine seedling. It was being retweeted on Twitter without the name of its originator . Then it appeared on my Facebook feed. This time it was attributed to someone called David Read apparently from the site 'Return to Nature'. So off I go down the rabbit hole of the internet .... and come across this chap: Dan de Lion.

Yes - Dan de Lion.

Suddenly the study of fungal growth became fascinating. I rooted around his website. Dan is an American herbalist. He leads foraging walks, and has a fondness for semi-naked didgeridoo playing. If I didn't have domestic responsibilities I'd be on the plane right now.

Alas, you may have noticed, Dan de Lion is not David Read. He merely blogged the mycelium picture. Emeritus Professor David Read is a sober suited scientist who has written the definitive work on Mycorrhizal Symbiosis. So lets settle down and have a swift look at the symbiosis between plant roots and underground fungus. It is why we are here after all.

Prof Read says:
Mycorrhizas, not roots, are the chief organs of nutrient uptake by land plants
Plant roots and soil fungus have a mutually beneficial relationship. The fungus gains access to carbohydrates the plant makes from photosynthesis in its leaves, and the plant benefits from the soil minerals the fungus can access and its higher water absorption capacity.

The network of mycelium around one plant can be so extensive that it interacts with the system around neighbouring plants, with the result all plants within a community are linked together, chemically communicating and feeding together. Some people say that because of this connection underground a group of plants is not made of a number of single independent specimens but is one single organism. For example, if one dandelion within a group growing on your lawn gets eaten by the family pet rabbit the greater 'dandelion organism' continues to exist even though one part of it has gone.

Knowing this I like to look at the street trees that grow in suburban Manchester and try to think of them as one big tree spreading out under the tarmac and down along the road. It is good to see things differently. Our understanding of the world is not as complete as we generally think. A whole other universe carries on around us without our knowing.

Researchers are looking into ways of exploiting this plant/fungus relationship. The most obvious application is to increase the mycorrhizal fungi within agricultural and horticultural soils to improve crops yields and plant health. This also benefits the soil itself by improving aeration and moisture content. The fertility of the world's soils is decreasing, and the soil itself is disappearing so using this mechanism on a big scale could prevent that particular hellish pathway we are going down. It would also help with mopping up chemicals from contaminated soils.

As our dreadlocked guru says: