Friday, 14 June 2019

Do agricultural chemicals damage the soil?



Of course Peter Williams' soil is more fertile and contains more organic matter than the farmers' (other than his pasture) and so does your own
When John Humphries took it as a ‘given’ that chemicals damage the soil when questioning the new chairman of ‘Natural England’ (who failed to disabuse him) my hackles rose.
But could he be right?

Most of us welcome the new surge of concern about global warming and the need to combat the shocking destruction of the environment. I am deeply pessimistic that we will or are politically able to do enough about it. I desperately hope I am wrong.
I do hope that global interventions will be more enlightened than wood burning power stations and manufacturing fuels from food crops. Some governmental initiatives have not  been wise.
I fear politicians acting against ‘low hanging fruits’ to satisfy populist fears and not really doing anything worthwhile. There are however exciting new ideas and technological developments that are huge grounds for hope.

Soil destruction and attendant erosion when clearance takes place
A recent report has highlighted the extreme dangers of destruction of soils. Not a new concern, but of ever increasing importance with forest destruction and attendant soil erosion. New weather extremes and human intrusions accelerate this process. Not only is soil’s organic matter a huge reservoir of captured carbon dioxide, fertile soil is needed for both reforestation and high agricultural yields. (note trees can make a contribution to restoring denuded soils)

Don’t blame the farmers
High agricultural yields are essential if we are to feed expanding populations - even though it may be unfashionable to say so. Far better to use land efficiently than further intrude on natural landscapes to create new farmland from countryside.

This neighbouring field might look pretty but does not feed many people
Supporting high yielding crops with fertilisers and other chemicals does not mean that sensible use of set-aside to enrich rural environment cannot benefit both the landscape and efficient farming. 
Many farmers are the very best stewards of the landscape and it is in their own interest to preserve their soil.

The thrust of my piece today is that the real causes of soil erosion is human intrusion (and advancing climate change) and that the use and misuse of chemicals (in terms of soil) is a side show. To over focus on chemicals as a bogyman is an easy cop out for politicians.

Having doubts
At this point in writing this post I thought ‘Where am I going with this? Defending agricultural chemicals is such a minefield and introduces so many environmental issues.”
For example the use of pesticides is much debated and at least some of the multiple uses of insecticides and fungicides must have subtle effects on the soil. For example fungicides might kill mycorrhiza. There is so much to say about pesticides and the environment and not all is l bad. 
Without them world agriculture would be in a very fine pickle.

It’s just that today I want to make the case that the proper use of agrochemicals is not actually bad for the soil and in many cases such as using fertilisers might actually improve them - as illustrated in my earlier posts. 
Humphries’ populist illusion is so potentially harmful to sensible discussion.
There are many issues how chemicals and in particular pesticides could be better used but to discuss them today would be a distraction.
For example farm fertilisers are part of the problem of water pollution and safeguards in their use are important. This harm however is not exclusive to inorganic chemicals and applies also to organic manures, ploughing up grassland and excessive organic oxidation by cultivation.
Farmyard manure contains a lot of nitrogen too

At this stage I lost the plot and dried up!

New Scientist defends farmers and finds no evidence that chemicals are destroying our soils
My mission has been restored after reading James Wong. Apparently our Secretary of the Environment of all people recently stated that we are thirty years away from “eradication of soil fertility” because “we drench our soil in chemicals”.
How crass, how misleading and plain wrong. Heaven forbid his actions based on such nonsense. (Better make him Prime Minister instead? Oh no!)
James spent eight hours trawling academic literature to find any evidence for such a statement and found none whatsoever. He contacted six renowned soil scientists who roundly refuted such notions. They were keen to point out the world soils are in danger but not for this reason.

The best evidence Wong found for farm soils lacking organic matter was a study comparing garden soils with farm soils in Sheffield. They found our garden soils are more fertile! Surprise, surprise, I could have told them that has been true for hundreds of years!

James Wong also pointed out that some modern farming practices such as ‘ no till’ and sensible use of fertilisers in many cases are improving soils. 

Old farming practices were not as enlightened as you might think
He states that many old farming practices were more detrimental than some would have you believe. Wong was not wrong.

Links
These two posts bring us back to fertiliser in the garden
Are fertilisers a good thing?
This post provides links to most of my advice about fertiliser use





Wednesday, 5 June 2019

Myth buster Robert Pavlis is back


When is the best time to plant snowdrops?
For readers of his Canadian /US myth busting blog he never went away! Where do all his myths come from? His fertile mind seems to generate them from nowhere. When I started blogging I had perhaps twenty gardening stupidities in mind on which I could bare my own prejudices. In his two books he has reached over 200 myths and if you go to his blog there are more.


Robert Pavlis also writes about orchids and ponds
When I received his e-mail to tell me he was forwarding his new book Myth-buster 2, I inwardly groaned (I lie Robert, I am immensely grateful). The thought of ploughing through all those gardening inanities was too much to bare.
As ever of course his razor sharp mind picks up and dissects myths major and minor. His new book goes further than before in distilling from each myth sound advice on good gardening practice.
The patience of the man! From the worst and most shallow of social media chatter to real gardening anomalies he gives the same precise well researched documented analysis and is fearless in rubbishing snake oil salesman and those who peddle propaganda, distorted science and just plain lies.


He shows endless ingenuity to find myths in the most innocuous places. For example, trivial and silly gardening tips are dissected and given undeserved  attention. 
I lose the will to live when he tackles the value of some of the tat that none gardeners add to their soil. 

Some questions like “are plastic plant containers a danger to human or plant” uncover someone’s belief system and the answer covers half truths and myths alongside undeniable facts.

Snowdrops are best planted in the green - myth


If they are not growing I cannot find them
This illustrates how Robert can correctly find myths in sound advice! Every good gardener knows that snowdrops moved in the green (that is planted or transplanted as green plants) grows better than dry bulbs from the store. I myself expand this advice to transplanting right through from first emergence to complete dying down.
But of course Robert is right. Snowdrops plant perfectly well as green plants or dormant bulbs direct out of the ground whenever you do it (if you can find them in Summer) - with the obvious proviso of suitable planting conditions. Dormant bulbs are fine - even best if you lift and replant the same day. (This period of grace might in nature last for months in Winter when animals have dragged bulbs to the surface).

The difficulty with planting dry snowdrop bulbs bought at the garden centre or even from reputable bulb suppliers is that they might shrivel and even die in the rough and tumble of marketing, transit and display. 
I hope my casual unresearched concluding remark does not create a new myth - perhaps snowdrops in a sales display merely go hard and dry. 

Nitrogen fixing plants share their nitrogen with their neighbours - myth


Is it just the clover or is the grass dark green too?
As a so called expert one combs others work to find things one disagrees with. On the face of it challenging this long cherished tradition of gardening lore must be wrong. Reading on, Robert does not disagree with the long term benefits of an increased nitrogen resource when legumes decay into the soil, merely that they don’t directly share fixed nitrogen with their neighbours. 
Fixers keep nitrogen to themselves and even when they die most of the nitrogen goes into their seed. Indeed nitrogen in the dead haulm might be less than from other bulkier plants.
I do find it a little surprising that some plants might not form symbiotic associations where nitrogen is shared between them - but apparently not so. I also wonder if natural organic exudates into the root rhizosphere inevitably leak nitrogen.
Robert’s piece in the book confines itself to the association between grass and clover but he expands the subject on his blog. I did enter into correspondence with him when I sent him a picture of a glorious green patch of grass and clover shining out of yellow faded lawn at Edinburgh Botanic Garden two years ago.

The grass has still not seen fertiliser - perhaps it is some kind of demonstration?
Peter Williams and myself have been back up to Scotland  and eagerly pounced on the said patch and Peter took numerous photographs. Was the green just the dark green clover or was the grass extra green too? We concluded it was.
In itself this proves nothing. Could it be nitrogen from a fairy ring type fungus, could it be that the soil round the clover was more sheltered or warmer? You can’t jump to conclusions. 


We pored over the patches and think we found the grass greener
American gardens are different
Although we have so much in common in our gardens we Brits need to bare in mind that the book is written for a different gardening culture. One with different mores and expectations. I discern that Canadians and Americans are more victim to fashionable whims and bombarded with more devious products.
More significant the continent represents a huge land mass with large variations in climate and soils. Their gardeners might find conditions much more extreme than our own.
In the north it can be cruelly cold and in contrast when did we last suffer from problems of excessive light intensity on our trees?

When Robert talks about lawns he needs to cater for huge variations.

Did I find any errors?
In his analysis of myths I find almost total perfection. I might look askance at such things as his suggested soil preparation where there are so many variables - but then I would be equally vulnerable to criticism myself.

I did wonder about the odd ‘throw away remark’ but not sufficient to run to google.


Do I discern some magnesium deficiency on the old leaves or should I just call it senescence?
I prickled a little at the bald statement that tomatoes need no more magnesium than other plants. Perhaps it is true. American gardeners have a big thing about using Epsom salts (magnesium sulphate), for multiple purposes — almost all wrong.

We would have to have a serious conversation about Robert’s assertion that sandy soil evaporates more water than clay. What on earth does he mean?  (Inadvertent pun)
……It just dawns on me later that it would be along the lines that sand which holds significantly less water against gravity than water-retentive clay does release a greater proportion of this limited amount to evaporation and transpiration through the plant - but in terms of total loss it does not….  Clay provides a much greater water resource for plants (to transpire) than does sand.

Myths I like.
Mainly in terms of confirming my own prejudices I loved the following debunkings. Forgive me Robert for imposing my own spin.

1. You should give your lawn roller to your worst enemy

2. Raised beds need compost - myth
And by my own extension fertiliser enriched soil can be used for large pots.

3. You should clear up and not compost fallen leaves infected by air born spores e.g. black spot fungus - myth, it makes very little difference to future infection

4. “It worked for me, therefore it must be true” - myth

5. Analyse your soil before you fertilise - myth, only very rarely of value

6. Organic fertilisers are more eco friendly than inorganic ones - myth
Tell that to the sea bed
7. Using purchased bacteria and mycorrhizal fungi is a good thing - myth, it's a complete waste of time

8. Adding peat to your soil will acidify it
Partly true but very little and short term

Links

I wrote about snowdrops
I reviewed Robert's first book
Go to Robert's blog to find details of book
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Sunday, 26 May 2019

Lyndi’s field, Chapter two


Success and failure

A work still in progress
It’s nearly three years since I sprayed off the five foot high weed on Lyndi's very heavy clay soil. There has been no cultivation other than kicking holes made by rabbits and mounds made by moles.
I wish those folk who insist that their clay is so heavy that they must dig could see its beautiful soft crumbly structure.
I made my first visit this year in late February. The soil was a delight. I have seen this often before when the combination of frost mould and copious casting of worms work together to create wonderful soil.

It had rained heavily but with the cohesive  settled soil I was able to spray
Of course in last Summer’s drought there were cracks all over. It’s the nature of clay that when it dehydrates it contracts and this happens. It is nothing to fear - in fact in nature it is a very good thing. Cracks reopen in exactly the same place each cycle of drought and in uncultivated soil provide permanent aeration and drainage - right down into the subsoil. Roots penetrate into them and perennial plant roots continue to thrive within and alongside - sometimes for years.
Although benefits of none cultivation kick-in in the first year it is now that the serious benefits really come through. Long term improvement - as long as you don’t start fluffing around  destroying the structure

Regular readers will know that I have a similar project on Cathi's grass verge  (formally ground elder)

Many years ago I did the same for client and now friend Jackie Barber when I sprayed off the turf in an old horse paddock alongside Pottery Lane (subtle hint) to make three huge herbaceous borders with zero cultivation. Jackie had the advantage of very ample supplies of spent mushroom compost to mulch with. Her clay soil underwent the same transformation  - and you have never seen herbaceous plants better.

It is  bulky organic matter of course that speeds the transition - and unimpeded action of such as roots, fungus and worms. In Jacky’s case with the aid of her compost and decay of the original turf. 
For Lyndi the extra organic matter has formed from the original weed, organic root exudations in the rhizosphere, sprayed 'annual' weeds and animals and birds. In both cases organic build up is unimpeded from excessive oxidation by stirring the  soil!

Weed
Still weed free in early April
My February visit was the first for two months. I was in some dread that it might be very weedy. On my previous visit there had been more newly germinated weed that I would care for. 
It was now remarkably clean. I conclude I must in December have struck a perfect herbicide sweet spot - still conditions, warm spell and no rain for several days after spraying (not to mention fortuitously getting herbicide concentration optimally right)
It took only an hour to spray round - just half my knapsack -and the only obvious weed was some still surviving white and purple dead nettle which is becoming a bit of a problem as it is not very sensitive to spray. There was far too many poppy seedlings which I had foolishly allowed. Most of these were sprayed.
At that time of year glyphosate is very slow acting (but still efficient) and it must have taken most of the two months for the weeds to die after the December application

Problems
Mid May most of the Spring bulbs are over
Now nearly three years into the project it has almost achieved my original aims. They were always narrow, mainly defined by my self-imposed restrictions on my time and at seventy seven being no longer prepared to expend a great deal of energy in other people’s gardens for free. 

Cathi's verge in May
(I continue to do the village plot and do some specialist spraying in Bolton Percy churchyard and other than mowing and hedge trimming do Cathi’s garden which in truth I regard as my own. Readers will know I claimed anno domini as my reason to discontinue maintaining Worsbrough cemetery 18 months ago - it was such a long drive. Wonder how it looks now?)


Lyndi’s field looks really pretty for four months of the year and clothed with spring bulbs it has been like this three seasons now. The sparser Summer bulbs and still establishing fescue grass now make lovely little cameos for my pictures but overall it is generally scruffy. I just don’t show you!







You don’t usually see the pile of concrete originally dumped in the overgrown field or an old abandoned metre bag of sand, ladders stored next to the fence or rusting debris in the far corner. Lyndi’s former gardener never learnt that the field was not the place to dump his mowings! The site cries out for a few trees to be planted and weed free drifts to receive some herbaceous planting. My now self seeding fescues and certain other plantings would look better for an occasional light strim.

Because the only grass allowed is Chewing fescue it comes true from seed - pity about the wild grasses that blow in
The unusual feature for me in Lyndi’s field is that I am  attempting to grow un-mown tufty growing gorgeous green Chewing Fescue grass as a backcloth and ground cover to the bulbs and the other limited planting. This is in contrast to Cathi’s similar 800 square metre fescue grass verge where I have popped in monocotyledon herbaceous perennials at every opportunity. 
As readers know I have been selectively spraying out weeds with my knapsack for fifty years now; my philosophy being ‘take care of the weeds and the plants will look after themselves’. The only change now at both Lyndi’s and Cathi’s is that fescue grass is now allowed as an honorary plant. All other turf grasses are ruthlessly sprayed out as a weed. (You don’t need to know what the grasses are as long as you recognise fescue)
I had rather expected that such selectivity would have much increased the time of spraying. In practice this is not so and compares very favourably with my normal methods. Indeed on the village plot where I have established a substantial amount of fescue, weed control is speedier as the grass suppresses weed germination

Part failure and amended plan
There will be more Summer colour and unlike here at Cathi's, at Lyndi's I have this year sown annuals
Despite the above comments I have been very tardy at Lyndi's in getting the fescue grass going. I deliberately delayed starting scattering much grass seed in the first two seasons until the soils’s seed bank had been diminished and I now confess to being deficient in throwing grass seed around - albeit it only takes ten minutes of flinging each time I sow. At best there is only twenty percent ground cover. Last August the first fescue flowered and seeded and this has speeded up the process. Currently there are thousands of new tiny self sown grass plants. In fact I will leave future sowing to nature. (Only fescue, no other grasses remain and any new germinated coarse grass seed that blows in is pounced on with a very well directed low pressure spray)

There are substantial bare patches especially when the multitude of Spring bulbs die down. Most of such soil is now covered by moss and looks rather nice.

New plan
I have not previously mentioned that there are now some well established patches of a lovely mildew resistant forget-me-not that reseeds itself each year. Elsewhere Love-in-a-mist fulfils the same purpose. (Not to mention the over exuberant poppies). These clumps are entirely grass free. I take this as ‘proof of principle’ that I can establish a much wider range of summer flowering annuals in my many spaces. I have purchased from Mole Seeds two annual ' throw and grow' flower mixtures’ to broadcast in mid April.
Please note that such techniques will never work in normal vigorous grassland. Indeed I will only scatter in bare patches.
I hope that Lyndi will have a colourful Summer.


My own throw and grow mixture at home last year
The above scene as I write looks exactly the same this year from entirely self sown seed from last year's plants.
Read that post here




Saturday, 18 May 2019

Why I will continue to use glyphosate with complete confidence


I wonder how long this landscape will survive now that I am no longer there to spray with glyphosate.

A blog comment came in effectively saying “what do you think of glyphosate now”?

My reply in substance said “ What kind of world do we live in when forty years of safe cultural practice with such a fine record over billions of distinct applications to the soil is damned. Glyphosate safety, repeatedly confirmed by the highest scientific authorities has now been challenged on very weak unscientific evidence. 
Why should worldwide use of a product with multiple benefits to mankind be decided by the winning team of silky tongued lawyers able to use all kinds of diabolical ruses to persuade juries deprived of anyone who has pre-existing knowledge?”

I am in despair as to how to present my feelings to my readers. As to actual practice, I will continue to use glyphosate as long as I am able! At seventy seven I need a continuing supply for at least another ten years…..

Apart from my fear that Bayer (and other companies) might be bankrupted by hysterical legislation and glyphosate sourcing resort to expensive black markets, I fear in the short term at gardening level too many will take the attitude  “ there is no smoke without fire” and stop using this useful and safe gardening aid. Worse that over-zealous  authorities will jump on the bandwagon in ill informed proactivity. Already in Canada and several States of America  garden pesticides are unavailable to amateurs.
Nothing in recent court cases has brought any accurate new scientific factual information to the table.

I worry that my readers think I have lost the plot and that this old boy is too dyed in his ways after using glyphosate as an essential part of his gardening and land management for the last forty years! Not so. If any credible evidence comes forward that glyphosate is dangerous I would say so

In a sense the fact that glyphosate is perhaps one of safest agrochemicals ever invented is part of the problem. Any manufacturer who claims total safety leaves itself open to contradiction. In truth no chemical exists that has never harmed anything or anyone (And lets face it, glyphosate is very toxic to plants).
It might make more marketing sense if Monsanto promoted its product as needing more safety precautions. It would be less open to completely plausible individual cases of sickness or death that are inevitable even when there is no causality. Indeed a product that has many millions of users is bound to accumulate thousands of accusations

On the smoke without fire theory some readers might wonder why millions of people reject glyphosate. On the other hand many million more after serious consideration don’t  - and for many farmers and growers it is an essential part of their livelihood  bringing healthy cheap food to our tables.
There is a body of people who believe that all pesticides are the work of the devil and are ever ready to accumulate evidence against them. It can be very convincing when presented as emotional propaganda. It might be misrepresented facts, dubious research or downright lies and misinformation. We live in a world where huge bodies of people passionately believe things that are plain wrong. Our personal lists of mass folly might differ. Mine includes homeopaths and anti-vaxers. If I confided my other prejudices I might lose my readers.

I have a secret theory that all pesticides have a limited life. They just accumulate baggage and are doomed. It is amazing that glyphosate used more than any other pesticide has survived near on half a century. To me that is testimony to its safety but I fear that it will join the long list of honourable and in some cases not so honourable garden chemicals no longer available.

Let me address the problem of American hyperactive punitive legislation another way. There are millions of users of glyphosate. Sadly there are hundreds and thousands and tens of thousands of us that share the most horrible diseases. It is pure arithmetic that many sick people will use glyphosate when there is no causality. Emotional presentation of individual cases will always sway juries.

Can it be that there really are people to whom glyphosate is toxic? In a world of billions, all with subtle biological differences it would be quite surprising if there were not rare cases. I would make this comment about any substance, chemical, food, medicine, cosmetic, sun screen, soap, detergent or pesticide in the public domain. Of course if as with peanuts such ‘allergies’ are not uncommon we should be told. I know of no evidence of this with glyphosate but there might be.

Let me go further. Is there any possibility that this chemical that on any measure of safety is similar to water or in the case of its wetters and spreaders the same sting in the eye as soap can actually kill anyone? (soap of course might). 
Yes it surely can if you consider the placebo effect.  And what follows might equally apply to any of the materials listed above.
This is not a silly whim. Science universally accepts the placebo effect where a person’s expectations substantially effects what actually happens.
Most of us feel better - and sometimes are - when we have been to the doctor even if we are given no more than assurance. In some trials people have been told their treatment was a placebo and they still got better. (Yes I know time is a great healer).
Less recognised by the public - but well understood scientifically - is the nocebo effect which is perhaps much more powerful. If you believe something will harm you it very well might. There is very convincing evidence for this phenomenon.
Suppose an employed gardener on instructions repeatedly uses glyphosate but believes it to be harmful and resents having to use it you can be sure it will do him no good. A witch doctor’s pins work very well.
Of course such argument would be laughed out of court. We do not live in a joined up world and you could never prove this had actually happened in individual cases. No doubt anyone with a real mental aversion to glyphosate might feel ill every time he sprays and such belief might wrongly sway juries.

Considering people’s fears about glyphosate
When I read the popular press report on any scientific research about almost anything at all they invariably draw the wrong conclusion and present their own often sensational speculation as having been demonstrated by the actual scientists. Worse the scientists themselves (and their publicity seeking employers) sometimes jump to the same bandwagon - especially those who start from a biased position.

1. Glyphosate has been found in the urine of just about all europeans.
Thousands of all manner of industrial, domestic and natural chemicals are excreted by everyone. The sensitivity of analysis is quite magical these days and can measure parts per billion. Such is way-way below levels of any possible biological harm. It does demonstrate that our kidneys are doing their job. It in no way demonstrates that such minute quantities do any harm. 
Some of you might  imagine my own urine is pure glyphosate.

2. Monsanto do terrible things
They don’t get much good publicity and I consider below some specific activities. Dislike of their methods is no reason to deprive the world of their remarkable product. Out of patent, anyone can make it (thank goodness - it might enable its survival)

3. Glyphosate kills earth worms
Surely in the laboratory they do not like to be daubed with soapy materials at near neat concentrations but there is no evidence that these lab concentrations much much higher than would ever be created  by the most enthusiastic farmer do in the soil any harm whatsoever. I associate no till soil, usually facilitated  by glyphosate, with remarkably high worm populations. 
As readers will know a particular attribute of glyphosate is that it breaks down in the soil and does not build up at all.

4. The world health organisation declared glyphosate ‘might be toxic’
What a remarkably ridiculous concept only delivered under intense political lobbying.Anything might be toxic. Thousands of materials in our every day environment are carcinogenic (and are recognised as such) and we closely encounter hundreds every day. Sausages and bacon sarnies anyone?   

5. Growing roundup-ready crops is questionable
Some scientists think crops sprayed overhead with glyphosate might be less nutritious - and this may be so. I do not know if this is ever truly significant but is nothing to do with whether it is safe in your garden.

6. Roundup-ready crops tie growers into buying expensive seed
What has disapproval of Monsanto have to do with using glyphosate in your local park?

7. Roundup-ready crops have been bred by ‘genetic engineering’ 
Most of us are past the concept of frankenstein foods but debate about interfering with heredity goes on. It’s no reason to reject glyphosate.

8. Use of glyphosate depletes the countryside of wild flowers and insects
It is the very nature of farming to eliminate  weeds to enable growers to produce healthy high yielding crops. Glyphosate is second to none in achieving this purpose and does so much better than soil damaging cultivations and in the round much better, cheaply and more safely than alternative chemicals or such daftness like acid or flames.
Unfortunately one man’s weeds are another’s wild flowers. Most agricultural weeds are not wild life friendly but some are, beautify the fields and host insects. Many fine native plants are rare.

There is a real issue here about farming in general. There is a need for land management that sets land aside for wild flowers, hedges and trees. I would go further and mandate seeding and planting of (not exclusively native) fine plants of the world. Properly used glyphosate is a tool to help achieve this aim

Of course glyphosate can be used to destroy rich ecologies. Don’t blame the tool, blame the operator. Not the plough, not the chainsaw, not the drain, not the weedkiller.

Why the loss of glyphosate would be a world disaster
Substantial increase of carbon dioxide emissions
Although many organic growers and ordinary gardeners  achieve minimum cultivation without using chemicals, for most worldwide farmers, growers, land managers, fruit growers and almost anyone raising land based commodities it is almost essential. Roundup enables minimum cultivations. Excess cultivation oxidises away organic matter and returns carbon dioxide to the atmosphere.

The costs of world food production would rise considerably

Yields of many crops would fall

There would be more use of dangerous energy intensive polluting machinery and alternative and less safe chemicals

Final comments
You will rightly inform me that not all the issues I consider today are relevant to impending court cases destined to either the collapse of glyphosate production or at the very least greatly increase its cost. Indirectly however, misinformed public opinion greatly increases the atmosphere in which court cases are settled.

In denying homeopathy earlier it is not lost on me that its purported successes must be placebo!

More thoughts about the world impact if glyphosate ceased to be used
I find little authoritative assessment of the global cost if glyphosate became unavailable. It’s scale is so vast and in agriculture and land management it’s uses so diverse that I am incapable of doing other than offering my own opinions based on my own limited experience and I hope intelligent deductions. There is a real need for this information to understand implications of cavalierly casting glyphosate away 
As I have suggested above, glyphosate is a major facilitator of minimum or zero soil cultivation techniques and reduced cultivation is now embedded in almost all conventional growing.
This is relevant to soil disturbance causing oxidisation of organic matter and apart from reduced soil fertility, millions of tons of carbon dioxide being dumped into the atmosphere. Further, every time a soil is loosened by inevitably increased cultivations it is much more susceptible to erosion. Soil erosion has been pin pointed as one of the great disasters of global warming and is accelerating as rainfall and stormy weather increase.

Link
I have posted before about implications of losing glyphosate to the amateur and local authority markets. How much worse if farmers cannot use it.


Better than brambles and nettles


Wednesday, 8 May 2019

Reasons to dig



The joy of digging (perhaps when you finish)
I have discussed this before! When I embarked on blogging as a no dig gardener and as a former lecturer on soil management I welcomed the opportunity to look in some detail at the harm done by excessive cultivation and - in the other camp - why gardeners actually dig. 

The logo for my series
To this end I started two series, one on why digging was harmful, the other on reasons to dig. In these articles I tended to discuss single issues in more detail than is possible in a lone post.
To be honest I was a little disappointed with the interest they created. Most gardeners are more concerned about growing their plants than contemplating their soil.

My article today attempts some kind of summary of the reasons to dig and at the same time to aid gardeners link back to old posts that provide more detail. After more than 400 blog posts things can get lost. Just as well you may be thinking and indeed there are some I would like to forget.

What is digging?
I suppose it really means deeply turning the soil. In its purest form single or double digging inverts a complete plot either in preparation for new planting or (ugh) between established plants.
A visitor caught me with a spade
When I describe myself as a no dig gardener the above definition is what I mean. 
I am a minimum cultivator who eschews unnecessary soil disturbance but one who recognises that soil will sometimes needs disturbing - not least for lifting and planting. My small border spade is always shiny.

It might surprise readers that this stainless steel border spade is my favourite tool
In my posts reviewed today my definition of digging is much vaguer. It includes general soil disturbance with spade, fork, hoe or shovel. It includes lifting, planting, hoeing, burying things, mixing, draining, level changes and much more.

Why gardeners dig, the good and the bad


In my old series about reasons for digging there is an undeclared spectrum of approval. At the nadir is the belief that true regular digging in some way improves soil health and aeration (and so does a single operation in rare conditions of compaction, either natural or more often as the result of a builder’s dozer or a pan from a farmer’s plough or rotavating indulgence). 

There is the issue that one cultivation leads to another and often creates the need for endless repetition. Those who insist on digging a heavy clay soil sow the seeds of the apparent necessity to dig again next year. Just leave it alone and let the worms and accumulation of organic matter take the strain.

These cracks on Lyndi's heavy clay soil will close with heavy rain
My intermediate state of my approval includes genuinely based well thought out systems of soil management chosen by gardeners. This might include those clever people who win all the shows!

Sometimes there might be a specific need to cultivate the soil. Perhaps to bury wood, paper or char. (The worms will bury the manure). I have no inhibitions to digging to enable such things.

Links to my old series
President of the diggers' union
1. Digging can be healthy exercise and good for the mind - especially for those who think it worthwhile

2. Rough digging exposes soil to the benefits of freezing. (but so might leaving it alone)


Frost mould - or is it worm casts
3. The gardening world is very confused about soil compaction and confuses it with  a well structured settled soil. Where true compaction occurs digging is a quick way to correct it

4. Digging is a speedy way to transform a weedy overgrown site into a clean planting area. This post describes proper single digging as recommended when we ‘dug for victory’

5. The generally unrecognised effect of soil cultivation is that it degrades organic matter and releases nutrients. Only a good thing if you also manure!

6. A gardener might want to amend soil texture by mixing in such as sand or clay. Be careful what you ask for.

7. This post looks at digging out debris. You have no idea what  toxic materials might have been deeply buried by previous owners. You might dig up something interesting.

You might wish to remove some stones
7. You should have no inhibitions about shifting soil around to adjust levels. Be careful not to mix sub soil and topsoil - except where it might be a good thing!


The levels are very varied in my bog garden
8.  Severing invasive roots. I have firmed up my opinion that this is not very effective and that loosened soil is an absolute magnet for invasive roots. Just look how tree roots grew upwards into Peter’s pile of compost



9. Burying wood and such as woody prunings, hedge trimmings  and newspaper in a trench a spit down is surprisingly beneficial to the soil.
I confess now that my straying into hugelcultur was a complete failure as a result of my (predictable) lack of watering in dry weather and failure to cover with sufficient soil.

As to my regular use of a spade I compiled a list of fifty uses of a spade (well not quite). Other uses have come to mind since - yesterday I used my spade to scrape ivy off a wall!



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