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Phil, I'm really surprised you've been tempted to fall for the spin from a peat producing protectionist business organisation, and for the recycling of its pro-peat propaganda by Elzinger.

It's very telling that the one inconvenient truth he leaves out of his 'let's all love peat' piece is that peat bogs are hugely significant carbon sinks which lock away vast amounts of carbon. When we dig peat up, it oxidizes and releases carbon dioxide, the principal 'greenhouse gas' which is a major contributor to climate change (which incidentally speeds up the decay of peat bogs globally, leading to yet more - you guessed it - release of carbon). In fact this begins the moment peat bogs are drained.

Any resource is only 'renewable' if it is replenished at the same rate as which is it used. Peat grows at 1mm per year, yet on average we rip 200mm from a peat bog each year. Just because there is lots of the stuff does not make it a 'renewable' resource. It's time for a reality check. I've written an article exploring the delusional idea that peat is a renewable resource, which contains some interesting facts and figures on how much carbon is actually released by peat composts:

http://www.kitchengarden.co.uk/news/the-peat-delusion

Gardeners in the US suffer from the same disinformation campaign on peat use as we do here in the UK (ably assisted by our gardening media). Linda Chalker-Scott, one of the 'garden professors' recently conducted an overview of the scientific research on Canadian peatlands over the last decade, which directly refutes Elzinger's points:

- Peat harvesting permanently alters the hydrology of bogs so that natural regeneration is impossible

- Sphagnum does not easily regenerate on degraded peatlands, causing the sites to become drier over time

- Species composition of harvested peatlands is not the same as on undisturbed peatlands

- The mulches used in peatland regeneration decompose and become significant sources of carbon dioxide

- Natural peatlands are long-term sinks of atmospheric CO2, while mined peatlands increase atmospheric CO2 levels

- Amphibian populations, already hampered by acid deposition, are further threatened by peat mining

- Volunteer birch trees on abandoned peat mines accelerate water loss

The full post can be read here (it contains a link to a useful paper written by Chalker-Scott debunking the myth that peat is environmentally friendly).

https://sharepoint.cahnrs.wsu.edu/blogs/urbanhort/archive/2010/12/15/a-sustainable-resource-oh-for-peats-sake.aspx

Whether anyone thinks peat bogs are a sustainable resource matters not a jot. Opinions, of course, are not facts.

Although restoration post-extraction is possible, it is costly (Lancashire Wildlife Trust have done some great work, but emphasise that it is not without cost). Without intervention, they are likely to revert to dry heath vegetation and eventually scrub, as the hydrology is permanently altered. These habitats do not naturally sequester and store carbon, unlike the peat bogs they replace. More often than not in the UK, after peat extraction land is flooded, used for landfill or converted to arable agriculture or forestry, which will only continue oxidising what's left of the peat to the atmosphere as the greenhouse gas, carbon dioxide.

It isn't just Sphagnum we should be concerned about. One of the reasons why the Aquatic Warbler (Acrocephalus paludicola) is on the IUCN Red List as vulnerable is loss of breeding habitat due to peat extraction: http://www.iucnredlist.org/apps/redlist/details/148383/0. Peat bogs play host to a wide range of internationally important species, which are threatened by peat extraction.

Dr Mark Reed
Director, Aberdeen Centre for Environmental Sustainability
Principal Investigator, Sustainable Uplands project

Peat is renewable in the same way that oil is renewable - slowly over thousands of years. The trouble is we are not extracting it slowly any more - we're ripping it out of extractable bogs far faster than it is being relayed. And the real crux of the matter is that we don't need peat for horticulture - there's many alternatives, some arguably having superior qualities to peat. We managed to grow without it before the 1960s/70s, so its time to start weaning people off it again now.

If something is replenished at the same rate as which it is used then it can be described as 'renewable'.

Fossil fuels (including peat and oil) are not replenished at the rate they are extracted, therefore it is wrong to describe them as 'renewable'.

Drained and mined peat bogs do not miraculously spring back into life and regrow at anywhere near the rate at which the peat is extracted, if indeed they do so at all. Peat bog restoration is expensive, heavily spun and not always the wonderful restorative act it is made out to be.

And where's the concern for all the other species that live in and on peat bogs? It's their home after all. Should they be evicted simply to keep UK horticulture 'competitive'?

Agreed, we grew plants before peat, and many growers now run successful businesses (and win Gold Medals at flower shows like Chelsea) without using any peat-based compost at all. Professional grade peat-free composts are widely available and are made from truly renewable resources such as tree bark.

We need to hear more stories from these folk and not be sidetracked by the 'poor old browbeaten gardeners' argument, which is a prolific red herring used by the peat industry to distract attention from the real issues that need addressing.

We grow in peat free, and have supplied Gold medal winning gardens at both Chelsea and Hampton Court.

What's the problem?

Thanks everyone for your comments...there's plenty to stir the grey matter.

John

Do you not believe the Canadian peat supplier's claim that only one percent of Canada's available peat is harvested?

Phil, asking me that question is akin to asking whether I believe it when a tobacco manufacturer tells me that smoking isn't harmful. It's a distraction, and I would be very wary of anything a peat producer was claiming as 'fact' without independent verification.

In any event, just because there is a lot of something doesn't endow it with the tag of being renewable/sustainable. Peat isn't renewable in the sense that it is not replenished at the rate at which it is extracted.

Peat grows at 1mm a year, but on average around 200mm is dug up from a drained bog each year. To make it a 'renewable' resource you would have to wait 200 years before you returned to the same spot and extracted any more peat. But of course it's not that simple. Peat extraction involves completely draining the bog and altering water tables etc in order to make the peat harvestable. The first thing to go is the thin living 'top' layer (i.e. the live mosses). The drainage also has knock-on effects for adjacent bogs.

The claim that only 1% of the available peat is harvested is smoke and mirrors because if you harvest only 1% a year, in 100 years it will still all be used up. Peat harvesting takes place on a vast scale in Canada.

Dr Mark Reed (thanks for your comment) has already pointed out that so-called 'restoration' of vandalised peat bogs (few other words suffice) is both expensive and not a panacea - the bogs do not somehow jump back into life and start growing again as if nothing has happened. Peat extraction brings about significant and often irreversible change to ecological systems.

And let's not forget the role of peatlands globally in climate change. The science tells us that climate change is a reality and that the main driver is human activity. We know from the science that undisturbed peat bogs store and soak up carbon from the atmosphere, and we know that when they are drained and destroyed for peat extraction that they release the carbon previously stored. And we know that rising carbon dioxide levels in the atmosphere are what is causing the planet to warm at alarming rates.

Let's not lose sight of the fact that peat extraction results in the often irreversible destruction of natural habitat and the species they are home to, that peat bogs help us keep our water sweet and play a role in guarding against flooding, and that bogs provide us with serene and wild landscapes in which to wander.

With so many positive benefits, and with proven peat-free composts readily available, why would anyone believe it's a good idea to go on using peat for gardening and horticulture?

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