
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.

The banana fiber paper is used as an organic carrier for either ultra-low dosages of nematicides (abamectin and fluopyram) or microbial antagonists (Trichoderma spp.) and is to be compared to unmodified paper.
This study is being conducted using potatoes and green peas as the test crops over five consecutive seasons. With the aid of a microBIOMETER® test kit, Janet will be able to assess the impact of the paper on the soil microbial biomass and thus will be able to determine whether the banana paper is effective or detrimental to soil health.
Wrap and Plant technology sources:
NC State explores promising pest-control strategy with high-impact potential for sub-Saharan Africa
Banana’s Waste, potatoes gain
Potato farmers conquer a devastating worm—with paper made from bananas]
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.
University study demonstrates legumes are more efficient at improving soil MBC than grasses
Under the direction of Assistant Professor Denise Finney, Kylie Cherneskie, biology student at Ursinus College, conducted an experiment on the impacts of nitrogen fertilizer addition on soil microbial communities. Kylie measured microbial responses using microBIOMETER®.
Click here to view the finished poster presentation. If you would like to incorporate microBIOMETER® into your classroom studies/academic research, we offer a selection of Academia Classroom Kits.
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.

“One of our primary objectives is that farmers succeed in putting biology back into their soils to ensure their natural fertility. We are therefore very interested in everything that lives in the soil, from earthworms and microarthropods to microorganisms (bacteria, fungi, nematodes). For us, microbial biomass is one of the most important indicators that help us understand soil biology. Fungal to bacterial ratio, which is a less documented indicator for the moment, remains interesting to observe in certain situations and is the object of real research by our R&D team to understand how best to interpret it.
We have been using microBIOMETER® for 8 months now to test the soil in different projects in our panel of biological indicators. microBIOMETER® provides us with quick and easy results on microbial biomass and F:B ratio which is a real plus for us. We can perform tests directly in the field and present the results to the farmers. Moreover, the affordable price of the analysis allows us to perform soil biology tests in projects where we had no affordable way to do so before.”
*CDA, Centre de Développement de l’Agroécologie, are affiliates dedicated to R&D and advisory.
We recently received the following questions from one of our customers and below are the responses from Dr. Fitzpatrick.
Part of my research is surrounding the soil organic carbon results we attained from microBIOMETER®, and I am wondering if someone from your team could provide more information on what this means relative to total organic carbon (TOC) in a sample and if they are comparable?
The literature shows a strong correlation between available organic carbon and microbial biomass carbon (MBC). Since your compost is not soil, the available organic carbon in your sample would be TOC and would correlate. MBC by microBIOMETER® is even better than that: a big number tells you that you have carbon and all the nutrients needed by microbes and plants.
Since MBC has correlations to TOC is there a formula or percentage to convert MBC to TOC? Or approximately how much MBC makes up a TOC number?
There is no formula to correlate TOC with MBC. TOC includes carbon that we consider stored as well as carbon that is easily available to microbes. Increasing easily available carbon for example by applying compost will increase microbes and eventually increase TOC, but as microbes rarely exceed 1% of TOC, it would have little effect on TOC short term. In long term stable systems we see a correlation but the correlation is not the same for example in forest as in agriculture as the capacity to store TOC is different soils under different conditions. In studying the effect of long term (40 years) different management systems at U. of TN on MBC and TOC, MBC by microBIOMETER® correlated with the TOC demonstrating the effectiveness of sustainable practice on increasing TOC and the positive correlation with MBC levels.
Does a high MBC usually mean a higher F:B ratio? And if so, could we draw any conclusions about carbon sequestration capabilities from that?
Generally as the MBC increases there is an increase in fungi. The soil food web is a balanced community. Some communities are more fungal dominated some less, but similar communities tend to have the same F:B ratio. It is generally believed that fungi, especially mycorrhizal fungi, contribute more to carbon sequestration than bacteria. This may be because glomalin is carbon rich and tends to sequester.
To further my understanding of soil/compost mixtures. I performed two microBIOMETER® tests. One test was on “active compost” which is compost in a medium stage of decomposition, and generates some CO2 and another one “finished compost” which is cured, ready for usage, and low CO2 production. However, I found that they had similar amounts of MBC and F:B ratio. Is this normal?
A study with microBIOMETER® at University showed a higher F:B in finished compost. The higher respiration/MBC indicates that your unfinished compost is still being digested — working microbes make more CO2. Holding MBC stable in your finished product is good.
Jeff Lowenfels, a valued advisor and member of our Board, was recently featured in the New York Times Sunday Magazine article, He Wrote a gardening column: He ended up documenting climate change.
For 45 years Jeff has written a gardening column for the Anchorage Daily News and over this time has helped adapt Alaskan growers to their much longer growing season. And in doing so has become a documenter of climate change.
Jeff joined Prolific Earth Sciences because he knew the only way to wean agriculture off synthetic fertilizers was to trust the microbes to deliver nutrients to plants. Jeff is the well-known author of the all-time best selling gardening book, Teaming with Microbes, as well as Teaming with Fungi, Teaming with Nutrients and DIY Cannabis all very readable, informative and available on Amazon.
Ariel White, a ninth grader at Pretty River Academy in Ontario, Canada, utilized microBIOMETER® in their science fair project titled Post Wildfire Forest Reboot Kit.
The project was awarded first place at their high school and chosen to compete at the Simcoe County Regional Science Fair. At the regional fair, Ariel was awarded a gold medal, Best of Earth and Environmental Sciences, Best of Fair, The Dufferin Simcoe Land Stewardship Network Award, and was one of seven students selected to represent their county in the Canada Wide Science Fair where they won a silver medal!
About the project: Forest fires have increased due to climate change, causing forests to burn down at an unbelievable rate. Now we need forests more than ever, yet they have been taking years if at all to regrow. This project explores the question “how can we boost the speed of forest regrowth after forest fires?”. For phase one of this experiment, each plant was graded for performance using tests such as success-rate, growth-rate, compost-value, and self-propagation. For the second phase, it was seen what effect this plant had on the soil microbiome; which is key to healthy, speedy plant growth and isn’t evident after fires. It was concluded that the morning glory substantially increased the microbiome health from inevident to healthy, and had an almost perfect performance score. These results are very important to our world’s future as they could help to deter climate change and repair our forests and their diverse ecosystems.
We were excited to hear from our long-time customer Marcelo Chiappetta of Chiappetta Agricultural Company on how his microBIOMETER® testing has been progressing. Below is what he shared with us.
“Here in southern Brazil the past 5 years we’ve been working with biological agriculture and changing the way we see and manage our farm; more and more like an agricultural organism. Taking care of microorganisms, plants, animals and humans and focusing on producing high quality grains.
Fungal and bacterial ratio is fundamental to know how our soil is related to what crop we grow. And now, after starting to brew compost tea and using compost extract, microBIOMETER® is helping us measure and understand the right recipe of carbon and nitrogen related to the amount of fungi that we want to build in our composts before adding to the soil. We see that good microbial biomass along with organic matter is excellent for our soils.
In practical terms, we see biological flowering in crop fields and this is the proof that we are doing a great job with nature. Our soil is our bioreactor, and we need to feed it with the right nutrients. The Brazilian biome is rich on biodiversity and as farmers and soil guardians we have a responsibility to bring life back to our farm again in a sustainable way of producing food.”
Click here to read more on Marcelo’s soil testing.