Soil Biology

Earthworm Engineers #4 – Manure & Earthworm Populations

Earthworm Engineers #4 – Manure & Earthworm Populations 1600 1067 Soilmentor

Welcome to the fourth and final post in our Earthworm Engineers series, where you can learn from some of the best science about the value of these amazing creatures. We’re so excited that Professor Jenni Dungait is now the editor of the European Journal of Soil Science – and she’s made some important earthworm papers open access for a month. We’ve picked our favourite four and summarised them in this blog series.

Access the earthworm archives in the European Journal of Soil Science, to learn more about the science behind on-farm worms!


#4: Quantifying dung carbon incorporation by earthworms in pasture soils

This study looks at the effect of different earthworm communities on the amount of soil carbon (within dung applications) shifted into the soil. They tracked this process by labelling the carbon with isotope tracing, which is a clever technique that gives a really specific picture of where exactly the carbon is moving to. The three main earthworm types were tested in different treatments: surface-dwelling worms (epigeic), deep-burrowing worms (anecic), and network-creating worms (endogeic).

First, the researchers found that with increasing inputs of dung, the abundance of earthworms tested also increased, presumably because the worms had a more consistent food source in these pots and could flourish!

Most of the tracked carbon was found in the soils top layer (0-75mm), although when the earthworm population included deep burrowing (anecic) earthworms, carbon from dung was often found at depths of up to 300mm, which shows just how effective these worms are at burrowing materials from the soil surface into its lower levels. The most successful treatments (with the greatest flow of dung shifted into soil organic carbon (SOC)) were those with all three types of earthworms present (epigeic, anecic and endogeic). So, a diverse population of worms is necessary for optimal dung break down into soils!

In pasture soils, dung left by livestock can therefore contribute to increased earthworm populations, as well as increasing soil organic carbon. This is important for the soils nutrient supply, and also helps to reduce CO2 levels in the atmosphere, which has potential to reduce the effects of climate change. In conventionally grazed systems, the quantity of dung deposited per hectare are less than the amounts used in this study, but it’s interesting to think about how this research adds to the evidence supporting mob-grazing systems, where livestock graze fields more intensively, and more manure is deposited per hectare as the stock moves through!


Earthworms are one of the best indicators of soil health – find out how to monitor earthworms on your farm.

Earthworm Engineers #3 – Organic vs Conventional Systems

Earthworm Engineers #3 – Organic vs Conventional Systems 5184 3456 Soilmentor

Welcome to the third instalment in our Earthworm Engineers series where you can learn from some of the best science about the value of these amazing creatures. We’re so excited that Professor Jenni Dungait is now the editor of the European Journal of Soil Science – and she’s made some important earthworm papers open access for a month. We’ve picked our favourite four and summarised them in this blog series.

Access the earthworm archives in the European Journal of Soil Science, to learn more about the science behind on-farm worms!


#3: The impact of soil carbon management on soil macropore structure: a comparison of two apple orchard systems in New Zealand

This study compares two sites of the same soil type under apple orchards on one farm. One site had been under organic treatment, with regular compost application and grass cover, while the other was under ‘conventional’ treatment, with regular irrigation, fertilisation and herbicide applications.

When testing for earthworm populations, the researchers consistently found more earthworms in the organic soil compared with the conventional soil. They also reconstructed the 3D ‘macroporosity’ structure of both soils using X-rays, and again found greater macroporosity within the organic soil compared to the conventional soil. This isn’t a coincidence! Macroporosity is defined as the network of pores with a diameter of over 0.3 mm in the soil, and earthworms are known to create these kinds of channels.

This increased macroporosity is important for several reasons. First, it is known to increase the rate that CO2 in the atmosphere is locked up as soil organic carbon (SOC), which both increases soil fertility and also has potential to reduce the rate of climate change. As expected, this study then found that the organic orchard had a 32% greater SOC content than the conventional soils! Increased macroporosity also improves the soil structure, as the stability of soil aggregates is increased, which allows more microbes to live in the soil.  

Denitrification rates are known to increase in anoxic, water-logged soils, which leads to increased emissions of N20, a gas that contributes to climate change. As a result, increased macroporosity reduces denitrification in the soil, by allowing oxygen to penetrate into the topsoil, and reducing the chances of water logging.

It’s amazing to see evidence of how organic techniques allow our earthworm friends to flourish, and how positive their presence is in orchard soils!

Read the fourth and final instalment of our Earthworm Engineers series here!


Earthworms are one of the best indicators of soil health – find out how to monitor earthworms on your farm.

Earthworm Engineers #2 – Arable Farming & Earthworm Populations

Earthworm Engineers #2 – Arable Farming & Earthworm Populations 5184 3456 Soilmentor

Welcome to the second in our Earthworm Engineers series where you can learn from some of the best science about the value of these amazing creatures. We’re so excited that Professor Jenni Dungait is now the editor of the European Journal of Soil Science – and she’s made some important earthworm papers open access for a short time. We’ve picked our favourite four and summarised them in this blog series.

Access the earthworm archives in the European Journal of Soil Science, to learn more about the science behind on-farm worms!


#2: Effects of different methods of cultivation and direct drilling, and disposal of straw residues, on populations of earthworms

This paper was written in 1979, and uses some pretty intense soil sampling methods (dousing the sample sites with formaldehyde to isolate worms) – we think they probably could have done with Soilmentor to count earthworm populations at each site!

The paper makes some interesting conclusions about the effects of cultivation on earthworms in topsoil. They tested the number of earthworms over four years on direct-drilled fields that were sprayed with herbicide before planting, and ploughed fields (of varying soil types). They found earthworm populations were consistently greater in the direct-drilled soils compared with ploughed soils, although deep-burrowing species were affected similarly in both treatments.

They also test the effect of spreading mulch on the fields compared to burning straw residue, and find (unsurprisingly) that earthworm populations were greater in fields where straw residue was spread rather than burned, particularly in surface feeding species. This surface debris becomes an important food source for the worms, and makes their diet more stable.

The paper also suggests that the extra earthworm channels created under no-till soils may help to reduce any compaction in the soil, as well as distributing organic matter and increasing drainage. The presence of worm channels may also allow plant roots to penetrate more deeply, which can also reduce compaction.

It’s nice to know that regenerative farming approaches have such a positive influence on the earthworm community. We’re really excited to speak at Groundswell this year on how to become a soil expert on your farm, and to learn more about the benefits of no-till systems.

Ready for to learn even more about the wonder of worms? Read part 3 of Earthworm Engineers here.


Earthworms are one of the best indicators of soil health – find out how to monitor earthworms on your farm.

Earthworm Engineers #1 – Ecosystem Services

Earthworm Engineers #1 – Ecosystem Services 5184 3456 Soilmentor

Welcome to the first post in our Earthworm Engineers series where you can learn from some of the best science about the value of these amazing creatures. We’re so excited that Professor Jenni Dungait is now the editor of the European Journal of Soil Science – and she’s made some important earthworm papers open access for a month. We’ve picked our favourite four and summarised them in this blog series.

Access the earthworm archives in the European Journal of Soil Science, to learn more about the science behind on-farm worms!


#1: A review of earthworm impact on soil function and ecosystem services 

This paper reminds us of the many reasons why earthworms are farmers’ best friends. We can separate earthworm species into three categories: surface-dwelling worms (epigeic), deep-burrowing worms (anecic), and network-creating worms (endogeic). All three of these worm types play an important role. In their soils, earthworms are considered ‘ecosystem engineers’, and they earn this title for several reasons…

First, earthworms actually create soil! Worms feed on leaf litter on the soil surface then bury the organic matter into the soil, allowing it to be mixed and decomposed, and eventually incorporated as soil organic carbon within soil aggregates. This same process also allows for nutrient cycling in the soil, which is helped by the soils’ increased surface area due to the networks of earthworm channels. In eating soil and moving it around, worms have even been shown to heal soils that are polluted, by breaking down the contamination.

The presence of earthworms improves the soil structure, as the pore network created allows for a higher ‘bulk density’ of stable aggregates. This pore network can also improve plant root penetration, and the water infiltration ability of the soil, by creating space for the water. The increased drainage and the creation of water-stable soil aggregates can also reduce runoff on farms, as well as soil erosion by up to 50%.

Photo from Jackie Stroud’s Earthworm Quiz on wormscience.org

As earthworms burrow into the soil and bury organic carbon, they also help the process of carbon sequestration – the locking up of of CO2 from the air into the soil. But this soil carbon can be re-released again as greenhouse gases, especially when the soil is disturbed during ploughing. The process of building up carbon in the soil is complex, and varies depending on how much organic matter is available to the worms on the soil surface.

Considering all of these earthworm endeavours going on beneath our feet, it’s unsurprising that this paper finishes by reporting that the presence of earthworms has been widely shown to improve the growth of plants above ground – they really are the engineers of their ecosystem! 

If you’re not all wormed out – read part 2 of our Earthworm Engineers series here.


Earthworms are one of the best indicators of soil health – find out how to monitor earthworms on your farm.

Will Godwin – Hampton Estate

Will Godwin – Hampton Estate 1440 1079 Soilmentor

The beautiful family run Hampton Estate is nestled in the sandy soils of Seale, near Farnham in Surrey. Most of the farmland is in woodland or grass and twenty years ago Guernsey dairy cattle grazed the estate. The family have since switched to a Sussex cattle herd and started producing grass fed beef to sell direct to their local customer base. Their cattle are raised on tasty grass and lovely Surrey sunshine! Hampton Estate are members of the Pasture Fed Livestock Association and in the process of having their beef pasture for life certified. Pasture fed systems with good grazing management can be very regenerative for soil health. Hampton have started using Soilmentor to monitor and understand how soil health is changing across their farmland.

The estate has some very special gardens filled with hops! This speciality crop has been grown in the local area for hundreds of years, despite a lot of production being wiped out by a fungal disease called verticillium wilt. Many other farms gave up their hop gardens, but Hampton has maintained growing this traditional crop with high biosecurity measures. Their hops are used in three major breweries across the country. The infrastructure required to grow hops is extensive and to fit in with the natural landscape Hampton uses tall poles made of chestnut from their own woodland.

Hampton are developing their farm strategy around building soil health and improving their sward. Using Soilmentor they can create a baseline for where their soil health is at now and give them an idea of where they want to go. Growing good grass is essential for their pasture fed cattle and so one approach they will take is to increase species diversity and deeper rooting plants in the sward. This will increase their resilience in times of drought as deep roots can reach water and nutrients further down in their sandy free draining soil. A more diverse range of broadleaf plants and root systems will increase the potential to sequester carbon from the atmosphere and put it into the ground. Hampton is monitoring the % of different plant species and their density to see how this changes over time in their pasture fields. As they collect more information about their pasture with Soilmentor they will be able to compare plant species readings with soil structure and earthworm readings to see if there are any trends and links in their improvement.

“I’d been looking for a tool to monitor soil health just like this, I’d tried other tests but they were always so complex and involved lab testing. It’s great to have a set of simple tests that I can do easily myself.” – Will Godwin, Hampton Estate

We spent the day soil monitoring pasture fields under different management approaches with Will Godwin. Will is part of the estate management team and works very closely with Bridget and Bill Biddell who own and manage the Estate on behalf of the wider family. Heading out to the field with Will and Bridget was great fun and the excitement about digging holes and hunting for worms was palpable! Will had expertly crafted an infiltration rate pipe from a piece of drainpipe, sharpening one end to make it easier to get into the ground. He used an old water bottle with 444ml of water marked on it to ensure the exact same amount of water was used each time. An old dustbin lid made an excellent examination tray for the soil block and Bridgett didn’t seem to mind us using her freezer bags to collect samples for the slake test!

We started on a very sandy permanent pasture field grazed throughout winter by their steers and very poached up in places. On this field we found no worms at all! This meant Will recorded an earthworm count of 0 in Soilmentor and we all agreed this is definitely an opportunity to improve how the soil on this field is managed to increase earthworms for the next time it is monitored. Next we headed to a permanent pasture field being rested after grazing last year which had an abundance of wigglers, seventeen in one soil pit, and even a dung beetle popped its antlers up. At the time we didn’t realise it was a dung beetle, but took a photo of it using Soilmentor so Will could look back at a later date to identify the beetle. This field had a dense thatch of grass on the surface which slowed the infiltration rate down considerably. The third field we tested was a grass field cut every year for hay which had a few worms but an exceptionally fast infiltration rate. In addition to these fields Will plans to monitor two more pasture fields and one hop garden.

Going forward Hampton plans to start a new grazing system, to improve sward quality and soil health across the estate. Changes in the way the herd is managed and trying mob grazing to encourage tall grass and deep root growth are central to the strategy. Over in the hop gardens, although they cannot return the biomass from the hop plants back to the soil due to the verticillium wilt disease risk, there are plans afoot with Rob, their Agronomist, to plant green manure cover crops in between the rows of hop plants. Verticillium wilt only affects broadleaved plants and to avoid attracting it to the garden the cover needs to be a cereal to mitigate this risk, so rye and oats are good options. The cover crop will anchor the soil, protecting it from erosion, photosynthesising and putting nutrients into the soil.

Soilmentor will help Hampton monitor how their soil is changing as they experiment with new farm management approaches to improve soil health. For example, with a new approach to grazing the fields over winter, such as mob grazing, Hampton will hope to see an improvement in earthworms, sward density and soil structure. All of these are what we call ‘soil health indicators’ and are easily monitored using soil tests with Soilmentor. All the information Hampton collects using the Soilmentor app is visually displayed on their online account making it easy to look back at their soil health records and analyse how things have changed over time.

What are Will’s management objectives:

  • Improve soil health across the estate
  • Increase grass and broadleaf species
  • Understand best grazing technique to optimise grass growth

What is Will monitoring:

  • Earthworms
  • Infiltration
  • Slake (Wet aggregate stability)
  • VESS (1-5)
  • % of undesirables % of bare soil
  • % of grasses, broadleaves, no. of species of each

 

Interested in using Soilmentor to monitor soil health and manage your farm both above and below ground?

Buy the app here and sign up for our newsletter

Are you a Pasture Fed Livestock Association member? Get a discount on Soilmentor, contact us or the PFLA for more info.

How do rhizosheaths tell the story of soil health?

How do rhizosheaths tell the story of soil health? 1080 1080 Soilmentor

If a plant has a large quantity of soil clinging to its roots, where the roots appear brown and not white, this soil coating is called a rhizosheath.

Why do we love them so much? They are an indicator of life in the soil: of biological and microbial activity in the rhizosphere, which is also known as the root zone.

Micro-organisms feed on root exudates and secrete binding agents which hold soil particles together around the roots in an aggregated structure, which indicates good soil health.

Soil structure is aggregating around the roots (photo from Niels Corfield https://twitter.com/niels_corfield/status/1070304660374855685)

“A simple way to find out what healthy soil looks like in your fields is to pull up some weeds! Don’t be surprised if you find rhizosheaths on these roots; weeds are often the healthiest plants in your soil.” – Niels Corfield, Soil Health Advisor

Watch the video below to find out how to assess rhizosheaths in your soil:

Fred Price, a regenerative farmer, describes how rhizosheaths indicate good soil health: “Seven years ago I didn’t know roots could look like this (see photo below)! The biological component of our soils mediates the soil-plant interface, increasing availability of nutrients and resilience to biotic and abiotic stress. So a well developed rhizosphere, the zone of plant influence in the soil characterised by root exudates, microorganisms and indicated by a healthy rhizosheath, is a great barometer for a highly functioning soil ecosystem. This vitality reduces the need for synthetic inputs, allowing the biological component to flourish further – this positive feedback cycle underpins any regenerative farming system.”

Rhizosheaths at Fred Price’s farm

Soilmentor can be used to monitor the development of rhizosheaths – you can score your progress in the app! Learn more about scoring your rhizosheaths with Soilmentor here

We plan to develop this scale to be more nuanced, so if you’ve been observing rhizosheaths in your soils we’d love to hear from you about your experience – info@vidacycle.com.


See our free online soils guide for soil tests you can do at home and find out how our app Soilmentor helps you record & learn how your soil is changing.

 

Know your Soils #12: The Soil Health Principles

Know your Soils #12: The Soil Health Principles 5184 3456 Soilmentor

Welcome to the twelfth, and final, instalment of our Know your Soils series sharing practical tips for monitoring the soil health on your land.

“If you can’t measure it, you can’t improve it.


7 Soil health mantras to follow on your farm

Insights from Niels Corfield, Soil Health Advisor

How do you build soil health? Below we share the six soil health principles to follow on your farm. Implementing farming practises and any new ideas which encompass as many of these principles as possible will get you firmly on the path of regenerative farming. With every decision you can use these principles as a checklist to guide you to the best tool to move forward to build a regenerative farming system.

 

 

1. Living Root

Living plants have living roots, they photosynthesise and transmit energy into the soil. This energy is feed for the beneficial soil organisms at work, creating aggregation in the soil.

2. Covered Soil

It’s best to have living plants in the soil, as then you have living roots. But the next best thing is to ensure you cover ground with plant residue, e.g. with a terminated cover crop

3. Minimise Disturbance

Ploughing disturbs the soil organism population, preventing them from doing their necessary work to maintain healthy soil. Reducing cultivation or going no till keeps them happy!

4. Diversity

A diverse range of plants in the soil means a diverse range of roots and a diverse diet for the soil organisms the roots are feeding. Roots have unique functions e.g tap roots bring nutrients up from deep in the sub soils and legume roots fix nitrogen directly in the soil.

5. Feed soils

Feeding the soil with compost, manure or compost tea will directly increase soil organic matter levels and provide plenty of food for worms!

6. Incorporate Animals

Grazing livestock in a rotation is beneficial for increasing soil organic matter, terminating cover crops and decreasing weeds in your fields. Why not try mob grazing?

7. Minimise Chemicals & Synthetics

Adding chemicals can undo the good work you put in for the principles above — pesticides kill soil organisms, fertilisers make plants dependent and herbicides kill living roots.

 

 

Microbial activity in the soil will lead to good soil structure; if generally improving soil health is your first objective then fostering microbial activity is a good place to start. Feeding microbes directly with manure or compost is one way to do this, or encouraging grass plants to grow bigger faster is another. Different grazing practises offer ways to achieve this too.

What management practises have you found useful for building soil health? We’d love to hear from you – send us an email to info@vidacycle.com

 


See our free online soils guide for soil tests you can do at home and find out how our app Soilmentor helps you record & learn how your soil is changing.

Hannah Steenbergen – 42 Acres, Somerset

Hannah Steenbergen – 42 Acres, Somerset 5184 3456 Soilmentor

Hannah Steenbergen is the farm manager at 42 Acres Farm , a 170 acre working farm and garden which is home to the 42 Acres Somerset Retreat Centre. Until this year much of the land was untended and wild, so there is an amazing amount of wildlife. Hannah’s plan is to create a small-scale diverse regenerative farm where they use minimal inputs, foster biodiversity and increase the fertility of the land.

“After we made hay the field was a buzzard playground! Hay making revealed all these small mammals. There’s amazing wildlife at the farm, we want to keep it that way whilst also bringing the land into production.” – Hannah, 42 Acres

On the farm she has introduced a small beef herd of Shetland cattle, which are 100% grass-fed and managed with ‘mob-grazing’.The garden, greenhouse and polytunnel are filled with delicious vegetables, salads and plants grown by Head Gardener Arek. There’s also a flock of Khaki Campbell ducks waddling around the garden and laying eggs. Hannah grew up on a biodynamic farm in North Yorkshire and is committed to following regenerative agriculture principles as she takes the 42 Acres farm forward.

The aim is to build soil health through clever grazing management with their growing number of livestock, moving them around the pasture regularly, ensuring grass has time to regrow and organic matter is continually incorporated into the soil. The farm is in a very wet area, so increasing the soil’s capacity to hold water is very important, that way they can prevent run-off and keep topsoil and nutrients on the land.

The Soilmentor app allows Hannah to monitor how the soil is changing, and if she is in fact moving towards her goals to build soil health at the farm. Her first soil tests clearly show where she started, and with testing every 6 months, she will quickly get an idea for how the soil is changing with each new farm decision and management practise put in place. Plus it can be fun! Hannah said “I particularly enjoy the earthworm tests, identifying the different types of earthworms is very interesting. The infiltration rate is also very interesting, it was completely different in our pasture vs roto-tilled veg plots. I feel like I’m understanding more about soils all the time.”

For Hannah it’s very important to become a financially viable small scale and diverse farm, with a social impact. As the farm is in its first year, Hannah and the team are figuring out what the land would be best used for, and the soil tests will give a good indication of things to try out. By monitoring and understanding the soil health now, she has taken important first steps to ensure healthy soils on the farm.

 

What are Hannah’s management objectives?

  • Increase soil health on the farm
  • Understand best grazing techniques and optimise grass growth
  • Maintain and increase biodiversity above and below ground

 

What is Hannah measuring?

  • % of undesirables % of bare soil
  • % of grasses, broadleaves, no. of species of each
  • VESS (1-5)
  • Earthworms
  • Infiltration
  • Plate meter

 

Interested in using Soilmentor to monitor soil health and manage your farm both above and below ground?

Buy the app here and sign up for our newsletter

Video series: How to monitor your own soils

Video series: How to monitor your own soils 1024 512 Soilmentor

To help you get started with soil monitoring watch our videos on how to do key soil tests, use the Soilmentor app and look at results on the website.

 

VESS TEST

Learn what to look for when you visually analyse your soil structure:

 

EARTHWORM COUNT

The best technique for counting earthworms in your soil sample:

 

SLAKE TEST

Watch how to collect a soil sample in the field and see how well your soil structure withstands water:

 

HOW TO ANALYSE YOUR RESULTS

How to log in to your Soilmentor account and analyse your results:

 

RHIZOSHEATHS

This is an additional test to assess biological activity, although not considered a key test. Find out what to look out for:

 

INFILTRATION RATE VIDEO COMING SOON..!


See our free online soils guide for soil tests you can do at home and find out how our app Soilmentor helps you record & learn how your soil is changing.

Know your Soils #11: The VESS Test

Know your Soils #11: The VESS Test 765 428 Soilmentor

Welcome to the eleventh instalment of our Know your Soils series sharing practical tips for monitoring the soil health on your land. Keep an eye out for our bitesize videos and fact sheets on simple tests you can do yourself on farm.

“If you can’t measure it, you can’t improve it.


How to visually assess your soil structure

Short video created by the Soilmentor Team

Assess the quality of your soil structure for yourself with a spade, tray, ruler and smartphone. Soil structure shows how much biological activity is happening, how well water can infiltrate downwards and how well plants are being nourished. It is core to soil health!

It takes some practise! This short video will show you what to expect:

 

Scoring your soil sample with the VESS chart

Once you have measured the top and bottom depths of your sample, you need to score each one using the VESS chart.

When scoring your sample the VESS guidelines encourage you to ask yourself: Are the clumps angular? Do they have roots running through them? How easy is it to break them down? How porous are they? With gentle pressure breaking them down what size are most of the clumps?

We found many farmers find these questions quite difficult. In the video we simplify the process: it is easiest to observe what soil looks like when you break it apart during the test. If the pieces are mainly angular then give a score of 3-5 and if they are mainly ‘bobbly’ or crumb-like give a of score 1-2. Don’t understand what we mean by ‘bobbly’? Watch the video and you will see! The app helps you with the scoring when you are out in the field too.

 

What does a healthy soil look like?

Well aggregated soil gets first prize in the VESS test! This means that the soil particles are in a crumb structure: there are smaller particles holding together around plant roots.

Soil is aggregated by biological activity; microbes and soil organisms digest organic matter and glue the soil particles together.

Aggregated soil is good because it allows air and water to percolate and store between the particles, which fosters plant growth and supports all soil flora and fauna to thrive.

Soil may lose it’s aggregation structure due to compaction or a lack of biological activity. If you work on improving your soil with the 6 soil health principles you can regenerate it, restoring it’s life and aggregation.

 


See our free online soils guide for soil tests you can do at home and find out how our app Soilmentor helps you record & learn how your soil is changing.