Francis Lawton an 8th grader at St. Timothy School in Los Angeles, CA utilized microBIOMETER® in his science fair project titled “The Effect of Greywater on Plant Growth, Soil Microbial Biomass Carbon, and Soil Fungi to Bacteria Ratio. Francis took first prize at the fair and moved on to the Los Angeles County Science & Engineering Fair where he placed 3rd in his category of Ecology. He also received a special award from USAID (U.S. Agency for International Development). Francis then took part in the California State Science & Engineering Fair in the category of Earth & Environment (Air/Water) and placed 2nd!
Have a science fair project coming up and would like to incorporate microBIOMETER®? Please contact us!
Project Abstract:
This project was designed to find out if greywater and treated greywater can safely hydrate plants, and promote plant growth, just as well as tap water. I live in drought-prone California and it’s important to find different ways of conserving water. My experiment tested the watering of grass pots with three different types of water (independent variable): Tap water, Greywater, and Greywater treated with Activated Charcoal. Over the course of 8 weeks, I measured plant growth, soil Microbial Biomass Carbon (MBC) levels and soil Fungi to Bacteria (F:B) ratio (dependent variables). Many controlled variables ensured a valid experiment. I hypothesized that each of the water types would result in the same growth rate, soil MBC and soil F:B ratio. My hypothesis, however, was incorrect. Greywater resulted in stunted growth and spiked the F:B soil ratio so high that the pot sprouted 13 fungi heads. Tap water and Treated Greywater, however, were equally good in terms of healthy plant growth and both pots had the two best average F:B ratios closest to 1:1 (which is the best ratio for grasses). Neither of these pots produced fungi. Soil carbon levels (MBC) fluctuated for all three plants, however each plant maintained an “Excellent” level. This indicated that each water type was fine for watering grass if you don’t mind stunted grass growth and some fungi in your lawn. My experiment also proved that Activated Charcoal effectively “adsorbs” chemicals in greywater that alter a soil’s F:B ratio.
Amy Gardner of Kalispell, Montana serves farmers in the Flathead Valley as an agronomy coach through her business, Lower Valley Consulting Inc.
Amy has been scouting soil health trials as part of gathering third-party research for the company AgriGro. Farmers have been applying AgriGro’s prebiotic technology to boost soil health and in turn grow more productive and nutrient-rich crops. Amy uses microBIOMETER® to help compare soil microbiology in the control strips and where the prebiotics have been applied. Other data points collected for the trials have included plant counts, soil moisture, tissue tests, soil tests, vegetative cover percentages, GreenSeeker readings, and root, plant mass and health observations. So far 14 soil health trials have been performed in Montana and Idaho. More trials are scheduled for the Summer of 2023.
Amy Gardner was born and raised in Kalispell, MT. She has her BSc in Agricultural Education from Montana State University. Amy is a Certified Crop Advisor, as well as a Precision Ag Specialist, through the American Society of Agronomy. She is passionate about helping growers build healthy soils to produce high yielding and nutrient-rich crops through precision management. Her and her husband enjoy the Montana outdoors with their 5 boys.
The microBIOMETER® was developed with the need in mind to deliver a device that could be manufactured very reasonably so that it could service the whole world. For over 50 years scientists have known that microbes are the best indicator of soil health. One of the common methods used for determining soil microbial biomass is the Chloroform Fumigation Extraction (CFE) test. However, being a costly lab-based test makes it an unattainable option for many. Another method that’s often used to assess soil microbial communities is microscopy. While microscopy is one of the best ways to assess soil microbes, microscopes can be expensive, are often too large and heavy to bring into the field, and are not necessarily easy to use or easily accessible for growers around the world. In 2014, Dr. Fitzpatrick began developing the microBIOMETER® to address these shortcomings.
The microBIOMETER® was designed to detect bacteria and fungi by their pigmentation on a specially designed membrane. An extraction powder was developed that contains different salts, which, combined with precise whisking, separates the microbes from the soil particles. The addition of this extraction powder also helps to precipitate the soil so that the microbes stay suspended as the soil precipitates to the bottom of the test tube.
Once the microbes are separated from the soil, they can be detected by spectrophotometry. However, like a microscope, a spectrophotometer is both expensive and too large to use in the field. The solution, in keeping with the goal of manufacturing a very cost-effective device, was to make it a lateral flow membrane. Almost all medical devices do a vertical flow, but a vertical flow has many technical problems. In a vertical flow, different types of membranes are put together and then a clamshell type device is used to press it down, but this pressure then has to be regulated. And Dr. Fitzpatrick, having worked with many clamshell devices, knew this method caused a great deal of seepage around the outside. A lateral flow, on the other hand, is more rapid than a vertical flow which allows the sample to be put on more rapidly than you can when you’re using a vertical flow device. The flatness of the device is important as well. Most other devices that are vertical have a rim around the area where the membrane is which is called a sample well. If you look down the well you cannot see the bottom because the well walls are casting a shadow. But microBIOMETER® is flat, therefore, a shadow does not pose a problem.
To perform the test, three drops are applied to the membrane in the test card. The microBIOMETER® membrane was carefully chosen so that it would not bind any of the common pigments you might find floating in soil. It only collects microbes on the surface of this membrane. The membrane also whisks away the liquid and traps the microbes on the surface. The color that it gives to the membrane can be compared to a grayscale, which tells you that the intensity of the color, not the color itself. The intensity of the color correlates with the quantity of microbes you have. Just like with the colorimeter or spectrophotometer, the intensity of the color is linearly related to the concentration of microbes. Dr. Fitzpatrick came up with this grayscale idea while thinking about a quilting secret. Quilters want to make sure they not only have different colors but have different intensities of color as well. Therefore, we’re not just measuring color but also measuring the intensity of the color.
The next step in the development was to figure out how to read the test cards. In the early version of the microBIOMETER®, a red filter with a grayscale was used, turning it monochromatic. A piece of red cellophane was put over the grayscale in the sample window and the results were determined by how dark the center was. This earlier version of microBIOMETER® is still being used by customers who are non-tech users.
At this point, the test could be read visually but it lacked precision, and data storage and tracking capability. For this, it was decided a phone app was needed. One of the barriers to lab testing in developing countries is cost, but another is infrastructure. However, cell phones are ubiquitous. If an app to read the test cards and store the data was created, soil stewards all over the world would have the ability to track soil health over time and assess their management practices while making changes in real time.
The challenge to the cell phone is that cell phones have a camera and manufacturers utilize different software. Therefore, the image viewed isn’t raw and overcoming the differences between various phones becomes necessary. The microBIOMETER® does that with the monochromatic grayscale backing. This in essence “tricks” all phones to be in the same range in their software and white balance. The issue of different color temperatures was also encountered. When you’re out in the sun on a cloudy day or you’re in the shade on a sunny day that light is extremely blue. When you’re sitting in your living room and you have a 60-watt light bulb, that light is yellow/red. And if you’re at the office with a fluorescent light that light turns out to be white -where red, green, and blue are all equal. Therefore, accounting for differences not only in cell phones but in ambient lighting conditions became important as well.
This stage of test development consisted of vigorous testing and a good amount of trial and error. The process involved running around with a test card from light source to light source with five or six different phones making sure the readings were consistent. By utilizing the camera’s flash in conjunction with a monochromatic backing, the images between phones became uniform. Once the patented algorithm that compensated for differences in light color and intensity and phone software was finalized, in 2018, the microBIOMETER® was released to market.
A few years later, in 2020, Dr. Fitzpatrick and Dr. Trexler tossed around the idea of adding another soil test to the microBIOMETER® platform; the fungal to bacterial ratio. During one of these discussions, Dr. Trexler inquired if there was a way to use size to differentiate bacteria and fungi. As a microbiologist, Dr. Fitzpatrick knew that bacteria are much smaller than fungi and therefore could be differentiated based on size. Dr. Trexler then wrote software that could detect and pick out the bacteria and fungi. It was discovered that when looking at a fungal to bacterial ratio on the microscope, a slight change in the color was evident; fungi are a very, very slightly different color than bacteria. There was a correlation between the color of the sample and the fungal to bacterial ratio that was detected microscopically, which turned out to be a groundbreaking discovery. After trying various methods for determining the fungal to bacterial ratio by color, it turned out cell phone cameras had the ability to pick up the difference. This discovery led to the fungal to bacterial ratio data being added to the microBIOMETER® app.
The following year, another exciting feature was added to the platform; Project Management (PM). A big advantage of reading results with a cell phone is that the data can be stored on the cloud. When the app was first written, there were a few different data fields for each sample. There was crop quality, crop type, soil class, and a couple other generic fields. It was soon realized that people using the test were likely more knowledgeable about what data and metrics assisted with farming. So, the app was updated to allow users to create their own fields based on their needs. This development was the release of Project Management (PM). Now, users can have as many fields of data as they want and it’s completely adjustable. Another benefit of PM is it lets users create a project and anyone on the team can upload their test results to the project. Before PM, everyone’s samples were on their own phone and in their cloud account. Now all the samples, regardless of who performed the test, are in one place and can be easily downloaded for analysis. Users can create as many projects as they want to keep trials separate from each other, but with all the data aggregated. There is one microBIOMETER® customer who currently has 20 different projects that match up with each of the properties they manage.
microBIOMETER® allows users to quickly determine if they are achieving the improvements they are looking for; track soil microbial activity over time and see how it varies with practice in order to assess what is working and what is not. With an innovative, yet inexpensive soil test like microBIOMETER®, $7 to $14 compared to much more expensive tests, growers can sample more per acre, allowing them to acquire a better understanding of their crops. With the ease of multiple sampling combined with data storage, users can view year over year and season over season results to see if their microbiology is increasing and if their soil health is increasing as a result.
It is important that the microbiology increases because there’s an incredibly high correlation between soil biology and soil health. We know that as microbial activity increases, so does the water holding capacity of the soil. It also makes crops more resistant to excess water – which can lead to erosion. Soil microbes build soil structure, which mitigates drought as well as flooding risk because it improves the texture of the soil. Microbes make a glue-like substance which enables them to stick to the soil. This stickiness remains after the microbes die and causes the soil to become clumpy. These clumps allow the soil to hold more oxygen, as it provides more aeration. Growers can improve the amount of carbon in their soil since the stored carbon in your soil is the bodies of dead microbes. When a microBIOMETER® soil test is performed, you’re looking at a snapshot of the microbes. They’re constantly turning over and they are food for other predators in the ecosystem. But that turnover demonstrates that you have a large number of microbes and that the entire ecosystem is being fed.
When you feed the soil ecosystem – from microbes to earthworms to mammals – that’s when you achieve the healthiest soil. Many creative and innovative practices are being developed that understand that healthy soil is part of a healthy system. The start is a healthy microbial ecosystem and microBIOMETER® gives you a glimpse into that very, very quickly. There’s nothing else like it.
This article is based on the video The History and Science behind microBIOMETER®
Created and performed by microBIOMETER® intern, Leanna Ramus, environmental science student at Siena College, this sample experiment is appropriate for high school and advanced middle schoolers.
The research project is designed to help students study soil health and understand the impact of soil biology on soil health and plant growth. Supplies are minimal cost and nothing recommended is dangerous or controlled. We expect students to use this as a guide to develop their own experiment.
We love supporting young minds with a passion for soil science. They are the future of soil health! If you are an educator that would like to bring microBIOMETER® soil testing into the classroom, we have three Academia Kits available for purchase. We are also happy to cater supplies to your specific needs. Please contact us for more information!
You’ve probably read how important it is for your soil to have a large, diverse microbial population, but how do you know that all those microbes are good?
Well to start, a healthy and optimal microbial population in your soil will always have a mixture of good and bad microbes. Together, these microbes perform important tasks to keep the soil functioning and the plants flourishing. Despite the complex relationship between plant and soil microbes, research suggests that soil microbes play a significant role in nutrient cycling, structuring plant communities, influencing plant performance and growth, and in disease control, which is why it’s so important to have a dense and diverse microbial community.
Thankfully, these soil microbe-plant interactions are self-regulated. And to keep these microbes functioning and plants thriving as they should, there’s a system of checks and balances that occurs within soil. For example, in a healthy, diverse soil mixture, microbes help plants suppress pathogens by inducing natural plant defenses, producing antibiotics, fighting against pathogens, or through the hyperparasitism of the pathogen. However, when there is an influx of pathogens in a not-so-healthy and diverse soil, things will start to function differently.
Once there’s a large enough influx of pathogenic microbes that have colonized within the soil, these microbes will produce chemical signals called autoinducers, which regulate microbial gene expression in a process called quorum sensing. In this example, quorum sensing allows those microbes to communicate with each other and change their genes to become virulent. Soil can become more susceptible to virulent factors if there isn’t adequate microbial diversity, as a diverse microbial community is critical to maintain ecological processes. To mitigate the negative aspects of quorum sensing, it’s imperative to have a diverse vegetation aboveground and a diverse microbial community belowground.
However, despite the good microbes’ best effort, soil conditions change and sometimes pathogens can take control. Depending on the pathogen, different physical signs and symptoms will become evident on the plant. Common signs of pathogenic disease on a plant can include foliage wilting, stunting, browning, and yellowing. Fortunately, because these are all aboveground symptoms, diseases can be easier to identify and potentially treat. Though, there are common belowground pathogens that affect the root systems of plants. These are more difficult to diagnose as they don’t always produce physical signs on the plant. The only way to specifically identify the pathogenic microbial species within your soil is to send your soil’s DNA to a lab for further analysis.
The best method that researchers have found to combat these soil pathogens is by supporting the good microbes, as the best defense is a good offense. Because microbial diversity has an almost linear relationship to microbial biomass, increasing the soil’s microbial biomass will increase its microbial diversity, which is the key to having a functioning and thriving ecosystem.
IngenuityWorx has been working to prove that the application of nanobubble oxygen as an irrigation/fertigation tool can provide low cost, easily applied plant benefits both indoors and outdoors.
It has been known for over 40 years that increased oxygen to plant roots in soil improves nutrient absorption, reduces effects of saline water or sodic soils, and increases plant growth and yields. However, traditional aeration technology prevented its use. Aerated water was limited to very short application duration and limited travel time in an irrigation line with low oxygen transfer efficiency.
The new science of nanobubbles allows us to add high dissolved oxygen concentrations, reaching 30-50 ppm, and the oxygen transfer will continue to take place for weeks. The nanobubbles don’t coalesce and break like macro bubbles, they move within the water using Brownian motion, and upon giving up all their oxygen produce small amounts of reactive oxygen species including hydrogen peroxide. This feature provides a built-in cleaning process that removes biofilm.
The microBIOMETER® analysis here shows that high dissolved oxygen in the irrigation water stimulated the microbial biomass and fungi to increase in number indicating a healthy microbiome in the soil for plant growth.
Additional work is ongoing to measure and understand the effects of the oxygenated water and microbial increases as it relates to soil carbon utilization, and its impact on carbon reserves and available nutrients. For more information, please contact bo*@***********rx.com.
An interview with the San Antonio Food Bank who is using microBIOMETER® in their Farm and Garden Program.
How are you using microBIOMETER®?
We are using microBIOMETER to track the soil health on our farms, gardens and compost. This test allows us to understand if we are providing an environment for our crops to thrive. Because we grow fruit trees, herbs and annual edible crops the fungal to bacterial ratio helps us identify the current soil health and help us understand what strategies we can look to implement to improve that environment over time.
How does microBIOMETER® help people understand the importance of soil biology as opposed to the historical focus on soil chemistry?
Traditional soil tests give you a window into what nutrients are or are not available within your soil. It can give you insight into how much organic matter might be present in your soil, but not how you might work to track progress on soil health, diversity or improving your soil food web on an affordable level. While knowing the nutrient breakdown is helpful information it does not help you understand if you are providing an ideal environment for those micro and macro organisms to thrive and ultimately aid your crops or plants in receiving those nutrients and so much more. The microBIOMETER® test kit has helped us better understand our complex food web and what strategies we can do to create a more balanced environment for our crops and our soil.
How did the microBIOMETER® information assist you with your project?
This test helps us to educate not only our staff on soil health strategies, but also our volunteers and anyone who attends are Teaching Garden classes. The data we collect helps us to showcase how the strategies we are employing to improve our soil health are making a difference from season to season as opposed to every two years from a traditional soil test. That enables us to make better recommendations to our community of growers about ways they can improve their soil, too.
About the San Antonio Food Bank
The San Antonio Food Bank takes pride in fighting hunger, feeding hope in our 29-county service area. We believe that no child should go to bed hungry, adults should not have to choose between a hot meal and utilities, nor a senior sacrifice medical care for the sake of a meal.
Founded in 1980, The San Antonio Food Bank has quickly grown to serve 90,000 individuals a week in one of the largest service areas in Texas. Our focus is for clients to have food for today but to also have the resources to be self-sufficient in the future.
Fighting hunger is our number one priority but we also serve to educate and provide assistance in many other ways. We achieve this through our variety of programs and resources available to families, individuals, seniors, children, and military members in need.
Our Farm and Garden Program consists of two locations and six growing spaces, including two farms and the garden at the New Braunfels Food Bank. Together these areas total more than 100 acres and provide 300,000 pounds of fresh local produce annually to our 29-county service area. We utilize 5,000 volunteers annually to assist with our operation and to provide local produce to the community.
Our Farm and Garden Program strives to provide quality, local produce to the community and to provide resources to teach those in our community how to grow food for today and in the future. In order to meet those goals, we start with our soil. By understanding our soil biology and health we get a window into what is happening at the root level and better understand the environment where our crops live and how to make improvements so we are growing healthy plants and nutritious crops. We believe everyone deserves access to nutritious fruits and vegetables.
Our Teaching Garden classes provide information about the importance of soil and composting as a foundation for building soil diversity and health. We utilize cover cropping on the farms and in our gardens to reduce erosion, build soil fertility, reduce weed pressure and increase organic matter. We create and utilize composting to increase the diversity of our soil, divert valuable resources from the landfill and introduce the community to the benefits of composting at home or in the community.
Zack Shier, Joseph Tree Service
Effects of Humate and Organic Based Soil Treatments on Urban Soil Characteristics
Zack Shier, Board Certified Master Arborist and Plant Health Care Manager at Joseph Tree Service, is utilizing microBIOMETER® in his study titled Effects of Humate and Organic Based Soil Treatments on Urban Soil Characteristics.
Introduction to the study. Urban soils have long plagued tree care providers with a difficult obstacle to tree health optimization. The very nature of how our urban soils come to be makes it quite challenging to diagnose the major issues with our soils, let alone correct those issues consistently, and with enough efficiency to make it affordable to clients.
When buildings or homes are built in our cities and towns, the natural layout and structure of soils is heavily modified, and often changed in erratic ways. Large holes are dug, bringing soil horizons meant for the deep areas, to the surface; mixing heavily with surface horizons. The top O and A soil horizons are often scraped clean to level surfaces, moving them or completely taking them away. Outside products, like “clean-fill” are often brought in, adding foreign soil or even rock (like quarry, limestone fill) into the surface soil area.
On top of this sub-par growing medium we’ve created, we also plant turf or put asphalt and concrete into most of the area. We then rake up and get rid of all organic litter and material, continually robbing the soil of the reincorporation of organic matter that forests are accustomed to. To add to the problem, urban trees are grown quickly using synthetic fertilizers on tree farms, and then dug up to be planted, cutting anywhere between 50-90% of their roots off, and often planted in different soil than they were grown in.
This entire predicament creates poor chemical, physical, and biological soil characteristics, resulting in poor urban tree growth, increased insect and disease populations, and high rates of nutrient deficiencies. (Read more)
microBIOMETER® can tell you if you are increasing the nutrient value and disease resistance of your crop.
A Rodale study showed greatly increased levels of the vitamins and minerals in sustainably farmed soils as opposed to mineral fertilized crops. And at Rodale, the sustainable practice yields are the same as the paired fields farmed with mineral fertilizers – and in bad weather, and disease years significantly better. Rodale is only one of many studies showing the increased nutrient value of organically and sustainably grown food.
Now Dr. Montgomery of the University of Washington’s team in a similar study has shown that if you are increasing your microbial biomass you are increasing the nutrient level of your crop: “soil health is a more pertinent metric for assessing the impact of farming practices on the nutrient composition of crops”.
Biklé, A. and Montgomery, D.R., 2021. Soil health and nutrient density: beyond organic vs. conventional farming. Frontiers in Sustainable Food Systems.
Hepperly, P.R., Omondi, E. and Seidel, R., 2018. Soil regeneration increases crop nutrients, antioxidants and adaptive responses. MOJ Food Process Technol, 6(2), pp.196-203.
Nature article reports that microbial biomass estimates by microBIOMETER® correlates with soil health and yield stability.
The microBIOMETER® soil test was used to report microbial biomass in a recent Nature publication*. Scientists Dr. Judith Fitzpatrick and Dr. Brady Trexler of microBIOMETER® collaborated with a University of Tennessee team headed by Dr. Amin Nouri. The team evaluated the effects on soil health and yield stability of 39 different methods of raising cotton over 29 years. The conditions tested included till, no-till, various cover crops and different levels of nitrogen fertilization.
The study found that the major impacts on yield were very dry or wet conditions, and low or high temperatures. The deleterious effects of these weather extremes on yield were mitigated by regenerative agricultural practices which resulted in adequate soil, C, N, soil structure and microbial biomass.
*Nouri, A., Yoder, D.C., Raji, M., Ceylan, S., Jagadamma, S., Lee, J., Walker, F.R., Yin, X., Fitzpatrick, J., Trexler, B. and Arelli, P., 2021. Conservation agriculture increases the soil resilience and cotton yield stability in climate extremes of the southeast US. Communications Earth & Environment, 2(1), pp.1-12.
