I believe that there is a very distorted view of soils in the construction sector. You don’t need to be a soil scientist to see it!
Industry professionals should do better when it comes to specifying and selecting soils that are fit to support valuable natural assets in our existing and future green spaces.
The UK is a nation of gardeners. According to the 2018 Horticultural Trades Association report, over two-thirds of adults visit the garden centre every year! That is a high level of participation by any standard, and so by this rationale, there must be a high proportion of designers, planners, and construction teams who also like to garden – a popular pastime which entails the genus and species selection based on soil type, preparation of the garden soil, careful feeding including the addition of (or making) compost together with dedicated watering, all to ensure that the garden landscape thrives!
By drawing upon horticultural principles, practiced at the weekend or basic plant biology knowledge learned at high school, our current trajectory is undeniable. The standard approach does not always consider the needs of the plant, tree, shrubs, and contents of the landscape, as central to the process of landscape design or soil installation. I draw the defendant’s attention to the copious stunted, struggling trees in supermarket carparks, serving no real purpose other than acting as a softer, less damaging bollard for your car’s front bumper. I rest my case.
Maybe we have allowed ourselves to be too reliant on and exploitative of Standards like BS3882:2015, passing up common sense for compliance instead.
“But clay means compaction which is bad, isn’t it?“
Not always.
Most trees and plants grow well with clay in the soil. This ingredient helps natural processes work efficiently, which supports the plant from the roots up.
However, it is the predictability under load that makes sand the perfect choice in certain situations, like golf courses, which rely on consistency over time, for their playing surfaces.
The Atterberg Triangle is often used to determine the texture of soil
The Atterberg triangle includes three vital components of soil: sand, silt, and clay.
At 100% clay, we may well make a dinner plate or pot instead of attempting to establish a rose. A completely silty situation, on the other hand, might exist at the bottom of a river – no room for growing our shrubs there either. As for sand; I’m thinking of the bright sand of a tropical beach or hot desert dunes.
Should we refer to a material that is more than 90% sand, soil?
Is the <10% ‘other’ sufficient for everything absent from the mix?
There has to be a reason that such sandy grow-media is prescribed.
I have written a lot in the past about how to sample soil, what tools you can use to make this process easier and how to plan your sample distribution for representative measurements. But how do you decide when to actually sample in the first place?
In this article I’ve broken down the process in to a series of simple steps or questions that you can reflect upon in order to help you decide when is the right time for you to sample. This means that you will have a (planned) approach ready before you even set foot on soil – making the whole thing easier.
To sample or not to sample? That is the question.
1) What information do you have about your land, plot or field already?
This will require you to know when you last tested the soil in this area. If it was more than 3 years ago, it is probably worth considering another test and if has been more than 5 years, it’s most definitely time to get that auger out again! If you have no data, how are you going to manage it? I recommend planning the annual budgets to cover soil analysis across an entire estate over a period of 3 or 5 years or in line with the crop rotations.
But, not so fast…
2) If you have already had a test, what did the results show?
If you implemented a programme of treatments or made focused applications due to imbalances or deficiencies (biological as well as chemical), you need to understand if there are sufficient concentrations still available/active or if things remain balanced. Chances are if you had a comprehensive analysis* within the last couple of years AND you have a good understanding of the effects of crop history, husbandry and organic/inorganic fertilisers or amendments you should consider a focused test to ‘sense check’ baseline levels and makes sure that they are in line with your expectations. A focused soil test may be slightly easier on your budget, although I do recommend spending as much as you can afford on soil analysis to ensure the most comprehensive data you can get. You only have one opportunity to collect data on your soil now and who knows what information you wish you knew in 5 years time. Over time this information helps you form a more complete story of your soil which is so valuable to drafting and implementing a long term soil management plan that will sustain the operation well in to the future.
*This would probably include Organic Matter, biology, minor and micronutrient concentrations in addition to major index tests and pH.
Timing
Collecting plenty of soil when sampling is always advisable if having multiple analyse performed
3) Sample history
Having established that this year is indeed the year to have your soil tested for a particular plot of field(s), we must then think about the precise time within the year. Data will generally be more helpful if it is comparative and so this means you should consider if repeat testing or scheduled cyclic analysis is it at a same time within the season or stage of crop as previous tests were performed.
4) Activity
If you sample now, will it be convenient to sample at the same date in 1,2,3 or 5 year’s time? It might be that at this moment in time there are exceptional circumstances and lower levels of grower/staff activity means that you have an (untypical) time and the capacity to sample and interpret results now, but actually you will be unlikely to have this opportunity at the same point in the season in coming years. This is so important because as mentioned before, you will want to build up a comparative picture of what is happening in your growing area, over time, by sampling at the same time in the season each time.
Fungi (zoomed in at 400 x magnification)
5) Active crop management
It may be that there are subsequent tests that you want to perform throughout the growing cycle of a crop – N, P, K, biological activities or mycorrhizal fungi etc. These can be treated as a one-off as they relate to that crop at that time and will inform a immediate and direct intervention, as a response.
Ultimately, managing soil health in the long run, is a ongoing process, a journey, rather than an activity you complete – Especially when intensively cultivating land. By thoroughly measuring your soil’s functional components, you are adding a Chapter to the story of how your soil works, every time you test.
6) Time of day
On an even more basic level, when we talk about the time of day that we should undertake the task of sampling, generally I would recommend earlier in the day wherever possible. The best time will be first thing in the morning, when plant sugar levels are lower and soil activity lower due to cooler night time temperatures and natural dormancy. Also, when collecting material for biological analysis, the Sun’s UV levels are also lower which ensures that microbial life in your sample are less likely to be affected (or destroyed) by the sun’s rays and is easier to protect bags of soil from heat and light whilst sampling other areas.
Conditions
7) Climate and weather
Natural and seasonal conditions play a huge role in determining your soil’s ability to function by directly (and also indirectly) affecting the Physical, Chemical and Biological aspects. Seasonal conditions may therefore affect the sampling timing. You definitely do not want to be sampling your soil during the height of a heat wave, monsoon or in middle of the icy, bleak mid winter so avoid any extremes.
Checking your soil temperature with a solid probe is a great way to get an understanding of expected biological activity
8) Temperature
Temperature is really key for any kind of microbiology testing and I advise, if possible, to avoid collecting soil material for microbiological analysis when temperatures are continuously < 8 Degrees C. These kinds of low temperatures will affect the activity levels of the different organisms – you will be analysing activity levels at a time when their natural tendency is to be less active. Also, depending on the extent to which soils have cooled and duration, total concentrations levels may also be less then what it is representative level when soil is warmer and fauna and plants and crops are interacting with one another.
The same is true of heat and it will not always make sense to test for soluble nutrient concentrations (those available to plant roots) or microbial activity when the soil is arid and absent of moisture. Both readings are liable to provide unhelpful readings when compared to real-world conditions for plant responses to properties that are critically dependent on soil water content. A more useful test in these circumstances might be soil moisture content itself!
9) Rainfall
Speaking of water levels, significant levels of rainfall can affect the amount and extent to which soil processes occur. An absence of water can hinder some key factors by limiting or disabling certain life-processes. The same is often true of excessive H2O, though for different reasons. Some elements can become increasingly (plant) toxic due to higher availability (more dilute in the soil solution) in conjunction with changes to basic biological processes. Oxygen levels are reduced in flooded soil. This can impair plant roots and effectively suffocates many organisms that can work for us, causing them to die or make facultative types (bacteria and certain protozoa) respond by multiplying to very large population numbers creating biological imbalances. You should therefore avoid sampling during and immediately after heavy downpours of rain.
10) Physical activities
Sometimes, our own interventions will affect conditions too and make it unsuitable to take soil samples for testing straight away. Examples of these times range from the application fertilisers, including organic amendments (compost, FYM etc) and inorganic substances such as herbicides, pesticides or fungicides. In almost all cases this will probably skew readings taken immediately after their application with effects ranging from incorrect soil organic matter % levels, overly optimistic soluble element concentrations and low concentrations of soil micro-organisms such as fungi. In all but a very few cases, including trial work or product tests, it would be more appropriate to wait until conditions settle first and this could mean waiting from between 2 days to 2 weeks** before entering the area to gather material for testing. This includes ploughing which by nature will turn the soil upside down, shaking up your data too.
** Refer to the product label or contact the manufacturer for guidance.
What you are testing for?
These days if you are not changing that makes you static. With the current economic and environmental pressures this static middle-ground is, in my opinion, a dangerous place to be. Many growers have already identified the threat and very real possibility of going backwards (in production) due to a decline in soil health and are more open than ever before to look at new (and old) ways of restoring and regenerating tired land.
There are so many different properties that you can test for, so it is worth some thought as to the value of what you choose to measure
11) Testing something new
Adaption is the key to survival and, hopefully, thriving. But this requires change. Testing the ‘same old things to inform the same old practices’ has already created many problems that we are struggling to resolve. Like Einstein said “We can’t solve problems by using the same kind of thinking we used when we created them.”
Traditionally soil testing has generally always consisted of texture and basic chemical analysis. Our knowledge has grown and we know better than ever before that this is more complex than we can currently comprehend and that Soil is far more than the sum of it’s parts. You can our (simple) take on the Science of Soil here.
If you are always taking (carbon) and never replacing, it makes sense that, at some point, you will run out. How will you know when, if you don’t know how much there was to start with?
So I say, test something new today!
12) Think further ahead!
You only get one shot at understanding the soil at a point in it’s and your lifetime. Soil is dynamic and if you are growing plants or crops intensively, conditions will change. Even if you are managing soil perfectly, perfection (if you are lucky enough to achieve this miracle) will have existed for but a brief instant and then cease to exist any longer, until you restore balance or leave the soil alone for nature to run her course.
Therefore, I always recommend having the most comprehensive analyses that you can afford. This means that you will have the widest set of readings to compare “before” and “after” for conditions, after growing something or implementing changes to growing methods and can truly determine the magnitude of impact. Budget will come in to play with this and so prioritise the information that you require first to ensure to help manage the day to day, whilst investing in new data to increase your (long term) understanding of this precious natural resource. An example could be adding soil organic matter and a biological index test to your standard (P K, Mg) soil index test. These nuggets of information might just open the doorway to opportunities within your soil that you never knew were available!
The process is mainly common sense, but hopefully by focusing on some of the do’s and don’ts, this article will help you eliminate from your calendar, those handful of times when you might otherwise have considered taking (and paying) for the analysis of soil samples that would otherwise leave you with a costly and less than useful report.
– Simon
BTW – If you’re looking to move in to a new/sustainable/more natural approach of managing your crops and plants and spoil microbiology is all new to you, you might be interested in checking out the 1:1 Soil Biology – Personal Plan that we’re now offering. This will give you direct access to expert testing and advice to start changing the way you think, use and interact with your soil.
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And, if you have any ideas for subjects that you would like us to cover, feel free to let me know.
Ever wondered what someone who runs a couple of soil related businesses including a laboratory and works for a tree consultancy does on a daily basis?
Look no further.
You donut! What are you wearing? Loaded with my mobile sample kit, I hit the road on my bike
The day starts, rather unusually, with a short ride on my trusty MTB – we’re off to the woods I tell you, to see what the teddy bears are having for their picnic!
I have all the kit I need to collect a sample of woodland soil in difficult-to-get-to places.
Well, actually we going to collect a woodland and hopefully fungi rich soil sample for some training that I’m doing with Soilbiolab next week. It’s cold…too cold really for this type of soil biology sampling (soil at the time was 5.2 Degrees C).
We shall have to do some magic in the lab to bring this soil fully out of dormancy!
All samples are prepared before then being put under high quality optics to assess the microbial concentrations.
Next, a quick stop at home to rinse off the mud* then I carry on the cycle to the lab in Andover, Hants. Look here: I am now dropping the sample off. This will now have a number of different extractions applied. Processing will be carried out over the next few days so that we can look at microbes such as bacteria and protozoa under a microscope in the workshop next week.
* I actually mean soil 🙂
This is where the bulk of my time is usually spent – which makes it some much more enjoyable when I get to go out and meet clients, or visit farms of clubs!
Most importantly, coffee is up next. But there’s no time to stop, it’s straight on to laptop work, emails and telephone for the next few hours.
Now that my prized payload of soil has had a chance to warm up a bit and burst in to action, time to have a quick sneaky check and make sure that it contains what we need it too (before lunch).
And now zoomed in at 400 x magnificationAnd here at 200 x magnificationThis is what we are typically looking at to measure – fungi, here shown at 100x magnification
And there’s the money shot…a beautiful bit of fungal hyphae filling the width of the objective!
Sometimes inspiration doesn’t come so easily!
After lunch, we’re back on it. Briefly. Telephone calls, quoting and emails are soon consumed by a general lack of interest and taken over by an attempt at some creative writing. For the next hour or so I try hard to finish off an article that I agreed to write for a soil related website about four months ago – an informative and hopefully inspiring piece for youngsters, if not slightly frustrated due to a heavily suppressed level of wit that I would really like to include!
We use a couple of different types of microscopes to train people in carrying out their own basic microbial analysis.
Onwards and upwards – there’s a Ball and cinderella must have her microscopes ready for the workshop next week! So, the final part of the day consists of me turning in to a technician and building up mechanical stages for five microscopes, to be tested and then re-boxed before we load everything at the weekend.
Just time for a couple of quick product photographs to edit and get prepare the text for adding to the web shop. This time, it’s for a new product- another awesome, low pH humic acid product to help condition soil and feed them microbes….
Time to hop back on board the two wheeled steam train and hot-foot it back home – ready to do it all again tomorrow.
That’s it. I’m calling it a day. I decide to leave the carnage until tomorrow when I’ll probably do something completely different.
I hope you enjoyed this little incite in to my world. If you did, please share it with others by clicking the button below.
CAUTION! This is seriously outside the box and possibly sensitive, but graveyards are great places to go – if you’re into soil.
As long as you’re not planning on staying indefinitely! 🙂
Think about it. The soil there should be really healthy.
Here’s why.
It is left undisturbed for relatively long periods. Traffic is restricted, mainly on a Sunday and for special events, and generally low volume – primarily limited to foot. And, everyone feels a bit funny walking over a grave don’t they?
Then you have the flora. The grass, hardy shrubs and trees.
Typically there is the odd Yew tree or two, abutting an ancient boundary or hedge or standing soldier-like on sentry on amongst the stone pieces. They are usually quite old and have co-evolved with soil itself, forming symbiotic relationships with the fauna that are too complex to comprehend, though will likely be significantly beneficial for fungi levels. The cover and the protection of the established green landscape and the shade afforded by the steeple tower, provide the first line of defence against climatic extremes.
Trees in grave yards can be old, solitary and often have co-evolved with the soil itself
Soil level is frequently elevated in the oldest of these traditional village settings. Contained within a wall, often many feet above other features in and around the site, like paths, gates and roadways. This is great for water drainage and maintaining optimal moisture content. I was led to believe (rightly or wrongly) that ‘coffins drifted underground’. Is this just an old wife’s tale or is the soil really so light, friable and free-flowing at this type of depth? I suppose it may be if it is occasionally being dug up and added to…
Then you’ve got the organic matter! Should be a pretty high %, shouldn’t it? We are made of soil, as we consume it, digest and absorb it in all its different forms. Eventually we are returned to it.
And head stones. Great supply of trace elements! As the granite or marble stone is gently eroded over time, years, centuries, the elements perculate through the soil, feeding it. Fuelling microbial interactions, nourishing plants and grasses.
If you’ve ever tested soil in a graveyard, I would love to hear your experience. Or, if you have ever pondered this question, and are strange like me, also reach out.
Different I know. But if you enjoyed it, we’d love you support if you can click LIKE below.
Well actually, no. That’s not really true. The principles of a healthy, correctly functioning soil are though.
Once you start to consider, even at a very basic level, some of the relationships and manner in which the different components of soil interact with one another, things start to fall in to shape and build your confidence in what you are doing or the new approaches that you are looking to adopt.
The aspects of soil are intrinsically linked and when balanced plants will generally grow better
You get the soil you’re given.
That much is true and whilst can be very difficult (and costly) to fundamentally alter the texture and manage the PHYSICAL ASPECT of your soil, a great place to start looking in to is the level of organic matter that your soil contains. Due to intense growing or mono-crop type situations, this is usually one of the first natural resources to decline. As a result, increased levels of nutrition or supplements have to provided in it’s place, often increasing the rate of declining levels of the soil’s ‘power house’ even more rapidly.
Organic matter can means different things to different people, depending on the industry you are in. In sports turf, it can mean thatch and is undesirable. So let’s differentiate here – we are talking about the the core reserves of carbon and organic compounds that drive the natural processes in the soil.
Thatch in turfgrass is not the same type of organic matter that we are concerned with in terms of soil function, though when degraded and can assist in a similar way
If you are looking to manage your levels of SOM you should understand the importance of the carbon and nitrogen balance necessary to enable efficient function: too high a level of C:N in your SOM and you are likely to rob naturally acquired nitrogen and even some of that which you are paying well earned cash to add to make your crops grow. An exaggerated example of this would be adding raw sawdust! If the levels of carbon too low in the SOM that you are adding then it is likely that you will struggle to support a meaningful level of microbial life – key part of the natural cycle that will make essential nutrients available to plants.
pH is of primary concern when considering the CHEMICAL ASPECT and nutritional demands of commercial crops and for this reason is often the most frequent and actively managed limiting factors in soil and growing media. It is vital importance that farmers, growers and managers obtain a comprehensive understanding of the different form and concentrations that the essential elements are present in. This requires a detailed soil test. The historic approach to managing limitations around this characteristic of soil has been a direct response using treatments such as liming, granular fertilisers or foliar feeds as the matter of course for dealing with issues surrounding crop nutrition.
The acidity or alkalinity of you soil will directly influence the availability of elements (foods) to your plants
Which brings us nicely to soil life and the BIOLOGICAL ASPECT.
Where does this fit in?
Well, everywhere actually.
It is neither more or less important than concerns around the physical and chemical aspects of soil. It is neither the start or the end of the cycle, however it is necessary throughout.
Fungi are the least common organism in cultivated soil
Whilst we may be some way off fully understanding the many different roles that the different microorganism play in the skin of our planet, we do know that where soil is working well (in a sustainable manner) it is prolific, diverse and BALANCED.
Bacteria help to convert atmospheric nitrogen in to plant available forms, fungi can help mobilise elements like phosphorus to plant roots despite soil tests showing low available levels of P, nematodes help maintain a balance of smaller organisms whilst releasing quantities of soluble foods in to the soil solution and warding off harmful plant feeder types (such as the Potato Cyst Nematode that has vilified this abundance and helpful creature!). Mycorrhizal fungi enhance the complex network of crop roots to help plants scavenge for other essential and micronutrients or obtain water in times of drought. The list of interactions and benefits goes on.
Plants are the driver behind many if the natural processes that occur in the soil, communicating with the life in the soil to obtain just what it needs, when it needs it.
The (micro)biology that we end up with in a field or pot of soil, is no coincidence though. The plant is very much the driver. Unseen to the naked eye, plants are slowly excreting minute traces of sugars and biochemicals (organic compounds, enzymes) that entice ‘just the right’ microscopic workforce for the job.
The order in which crops or plants are grown has a direct relationship to the type and number of microorganisms that will inhabit a soil
Needless to say, if you don’t consider the plant types that you are growing or cycling between with a crop rotation, and you are trying to develop or maintain a correctly functioning, balanced soil, the consequences could set you back significantly. For example, Brassicas or mustard are prime examples of crop types known to inhibit soil fungi and their introduction at an inappropriate point in a rotation, could alter the biomass and affect the all important ratio of bacteria and fungi in the rhizosphere.
This ratio will vary between different plant types. We wrote an article a while ago which explains this in a bit more details. If you want to find out even more get in touch with SoilBioLab.
A balanced ratio between the different types of organisms in soil or growing media will enhance crop performance
So there you have, simple – every action has a consequence and the physical, biological and chemical aspects of soil are all intrinsically linked!
We cannot yet fully explain how and why things behave like they do, however we do understand that under intensive agricultural and horticultural methods that we been applying for the majority of the last century and start of this, the long term prospects are not good. It seems that they are fast becoming even more costly in more ways than one. Any system that relies on the continuous removal of soil matter and the mineral fraction, at the detriment of the life that holds it all together, will ‘yield’ at some point.
So what to do?
Well, with your new found understanding of the simple principles of soil science, find your limiting factor(s) first and develop strategy to resolve or mitigate these.
Quite often this can meaning operating in one of the opposing aspects of the soil environment, such as increasing or balancing the microorganisms to reduce the impact of pathogens or nutrient deficiencies; or modifying chemical applications or introducing natural compounds to enhance effectiveness and build up nutrient holding capacity is another way (humic acid is great for this) or changing tillage practices to reduce the squeeze on the physical structure of soil.
There are more methods available then ever before and new technologies to help you address your limiting factors. This is supported by a rise of experts capable of supporting a Complete Approach to soil management – our core belief.
There are more than one way to cut a cake: understanding the size and number of slices is the first step, so investment in a comprehensive assessment of your soil will pay dividends in the long run.
Often referred to as ‘root food’ humic acid can help build up plant vitality and vigour through superior root development and enhanced chlorophyll function. It will also assist regenerative growth and reduce stress when applied as part of a well managed crop regime
Humic Acid (HA) is often included in many other products, primarily targeted at the organic sector, due to it also being an excellent source of food for microorganisms in the soil – it is known to increase levels of fungi (as a food source) and can even be used as an additive in compost tea. Those in the know already understand that it has many applications when used on its own and that it can also be used to enhance the effects of a great many other organic and inorganic products.
We are very excited to announce a new arrangement that allows us to sell a very high quality and unique humic acid product called BlackJak (property of Sofbey SA, Geneva) to new and existing clients. This compliments our focused portfolio of compost and microbiological products perfectly. It is also registered as organic under EU organic regulation 889/2008 to boot!
BlackJak is a really good soil conditioner and foliar feed for many plants and crops. You can even use it in compost teas to enhance fungal growth!
Due to the extensive benefits and established brand status (it is trusted and relied on by growers in 30 countries worldwide), we have setup our own page on Facebook for it here! It will help us spread the message if you Like and Follow while you’re there.
To coincide with our expansion in to humics, we have compiled a short list of reference material showing tests or scientific studies that demonstrate the powerful effect of applying what is ordinarily a major organic constituent of soil…
Please click on the links below. We anticipate adding more as we continue to develop in to this area, so don’t forget to signup for our newsletter to stay posted.
1) What information do you have about your land, plot or field already?
