With a small R & D grant awarded from the Dutch government, Jo Ploumen of the Netherlands is using microBIOMETER® to determine fungal to bacterial ratios in vermicompost filled in a Johnson-Su Bioreactor versus residence time. Jo also uses microBIOMETER® to measure microbes and F:B ratio in select soil samples as a member of a garden club. He found the differences by method of gardening; organic vs fertilizer and bare vs covered soil to be striking!
“I like microBIOMETER® as it is a cost-effective tool with a high impact, potentially,” Jo said.
Jo’s impressive resume includes studying Chemical Technology at the Technical University of Eindhoven, employment at multinational AKZO Nobel as an R & D specialist and co-founder of Pulsed Heat BV. In 2019, Jo founded Ploumen E.S. Compost to begin research based on the findings of Dr. David Johnson. Johnson is the developer of the Johnson-Su Bioreactor which delivers a compost with very unique properties.
We are honored to have Jo as a valued customer, data collector and partner on our journey to increase awareness of soil health, regenerative practices and carbon sequestration!
Photo source: Taos News
Microbial biomass (MB) is the best single indicator of soil health (Doran, 2000). Microbes feed and protect plants, build soil structure which prevents erosion, increase water holding capacity, and build soil organic matter (SOM). MB is low in any situation that is harmful to plant growth (and vice versa) and protects against pathogens, thereby reducing the need for pesticides. MB can predict success before plant outcome. The Fungal:Bacterial ratio (F:B) of the MB provides crucial information regarding colonization by Arbuscular Mycorrhizal Fungi (AMF), and the recycling metabolic processes of saprophytic fungi (SpF).
Soil stewards all over the world are seeking to understand the microbial levels in their soil and the ratio of fungal to bacterial life. The higher the microbial biomass, the more nutrients will be available to plants naturally, decreasing or eliminating the need for chemical fertilizers. Higher fungal to bacterial ratios are critical for building soil structure that prevents erosion and runoff off of pollutant chemicals while building moisture holding capacity of the soil and sequestering carbon.
Soil health is fast becoming one of the most important factors in agriculture and in the growing efforts to improve the earth’s stock of agricultural land. Farmers, industry, and environmentalists are looking for cost-effective and reliable ways to measure soil health and to assess impacts of progressive changes to soil and harvest management.
Testing soil in homogeneous sections at similar stages of the growth cycle can set a baseline for microbial biomass and fungal to bacterial ratio. That baseline can be used to assess how different stewardship practices are impacting the soil and allow for refinement to soil management plans and show soil health improvement over time. While every soil steward’s situation is unique, microBIOMETER® can help measure, follow, and assess efficacy of improvement to soil health.
Lyons Worm Works
Ben Rodman is a vermicomposter with a love for all things biology and horticulture. His vermicomposting operation, Lyons Worm Works, has grown from simply diverting and reclaiming their household organic wastes into a small-scale but growing community effort.
Combined with all the spent substrate from their gourmet mushroom cultivation and gardening and brewing waste, Lyons Worm Works creates high-quality, microbially dense and diverse living vermicast for regional consumers. For Ben, providing quality vermicast to customers means having objective measurements of its quality for multiple reasons: integrity and trust, quality assurance, marketing, and constant experimentation to improve his product and process.
“Experimentation and real data has always been important to me; bridging my idealism with the real world we live in and grow our food and medicine in. microBIOMETER® is giving me fast, quantitative data to assess important considerations like feedstock quality, evaluating the impacts of process changes, durability and storage for finished product, and for fine-tuning my compost tea kit recipes so customers can make high-quality aerated teas at home. Having a fast, accurate and objective way to assess my products provides me with the data needed to make informed decisions. It gives my customers and I confidence that my products are going to help them meet their goals. What a great product for the small producer like me, for whom a home lab isn’t practical and routine commercial lab testing is prohibitively costly!”
Many first-time cannabis growers don’t think too hard about the soil their plants will be growing in. If the soil looks healthy enough, it should be good to go, right? Well, it might be, but that isn’t enough information to tell for sure. If you really want to know whether your cannabis will thrive, you’ll have to see whether or not your soil contains a solid amount of microbes.
Microbes have a mutually beneficial relationship with the plants in their soil, and supporting microbes is one of the best ways you can support your cannabis. As we go along, we’ll be discussing the details of microbial presence in soil, the relationship between microbes and plants, and the specific organisms that make optimal growth possible.
Why Microbes Play a Vital Role in your Cannabis Plant Health
Microbes are key if you want your cannabis plants to grow as well as they can. If the idea of beneficial bacteria is strange to you, remember that we, ideally, have loads of bacteria in our bodies that keep us healthy. We’re not made of soil, of course, so things don’t work exactly the same, but the microbes in soil and those in our guts share key functions in common. Namely, as we’re about to explore, microbes provide vital nutrients to the plants in their soil, along with protecting them from harmful forces.
How Microbes and Cannabis Plants Work Together
With that in mind, let’s take a look at how the relationship between microbes and the cannabis plants you are growing play out in the soil. Plants need sufficient amounts of phosphorus, potassium, and nitrogen to survive and microbes have a direct hand in how much of those nutrients your plants receive.
While the nutrients may be in the soil already, they aren’t as accessible as they could be. Potassium, for example, is often shrouded in inorganic material. As microbes happen upon it, they’ll consume it, metabolize it, and excrete it in a form much more readily consumed by the plants. While the others aren’t as hard for the plant to get to, the microbes break them down nonetheless, and the plants benefit greatly from the enhanced access. This effort is further assisted by their ability to aerate the soil, ensuring there’s an even flow of water and nutrients.
The microbes aren’t only doing all this from the goodness of their heart, though. As the plants are fed, their roots excrete a collection of substances, called exudates, into the soil. These exudates, which include a variety of amino acids, organic acids, and sugars, happen to be a great source of nutrition for the microbes. With their microbe bellies full, the nutritional cycle is fully formed, and the plants are ready to thrive.
The Importance of Fungi for Growing Cannabis
While we think of fungi as separate from microbes, they’re part of the club too, and serve the same cause. To be clear, though, this is because they also partake in the exudates to stay fed.
Mycorrhiza fungi, in particular, can be found acting as the extension of plant roots, collecting nutrition from further down the soil than plants would be able to otherwise.
One type, ectomycorrhizae, acts as a sort of sheath for the root, extending out for nutrition. Endomycorrhizae, however, actually live inside the plant, helping to bring the nutrients straight into the root. To preserve them, ensure that you’re not being heavy-handed with fertilizers. Of course, you should also avoid fungicides entirely.
Microbial Dangers, and How Other Microbes Stop Them
As the fungi provide nutrients to the roots, they serve as a protective layer for them as well. But what, exactly, do they need protecting from? Well, among the beneficial microbes, there are thousands of microscopic worms, called parasitic nematodes, that feed on the roots of plants.
Looking from the outside, you’d notice roots facing attacks from ectoparasitic nematodes, which live in the soil right outside said roots (the rhizosphere). At the same time, endoparasitic nematodes are able to enter the roots themselves, breaking them down from the inside.
In anticipation of this threat, fungi will utilize their hyphae, which are the tiny strands that make up their mycelium. Using these strands, the fungi are able to locate and trap both types of nematodes, preventing them from further chewing at the root.
The fungi also receive help from, interestingly enough, other nematodes. They aren’t quite the same, though; while the others are parasitic, these are known as predatory nematodes. They, too, dwell in the rhizosphere, but only to eliminate plant-eating threats in the area.
How Earthworms Play a Part
Not every part of this underground battle is microscopic, though. In fact, the humble earthworm will be one of the main lines of defense for your cannabis plant. Parasitic nematodes happen to be a favorite prey of theirs, so they’ll munch up whatever your fungi and other microbes can’t catch. In turn, the waste they excrete contains nitrogen, phosphorus, and potassium (the three vital nutrients we mentioned earlier), along with calcium and magnesium. They also aerate the soil as they move around, ensuring the plant has easy access to the natural fertilizer.
How Benefits Show Themselves in Cannabis Plants
If you’re able to ensure optimal conditions for your soil microbes, you’ll notice it pretty quickly as your cannabis plants mature. Their leaves will be greener and fuller, they’ll end up on the taller side, and your buds will be notably larger and more resinous than average.
Your plant may be able to survive without a healthy amount of microbes, but it’ll look amateur in comparison. That’s not to mention the cost of those seeds adding up, leading you to lose money you could spend on expanding your growing operation. Armed with this new information, you won’t even have to worry yourself with the thought. Just keep those microbes and worms alive, and you’ll be on your way to hefty yields of potent buds!
microBIOMETER®, a rapid, on-site soil test, will help you determine the microbial levels in your cannabis soil as well as the fungal to bacterial ratio to ensure the healthiest environment for optimal growth of your plants.
Until now tests for microbial biomass were expensive and time consuming. microBIOMETER® costs $13.50 or less and takes 20 minutes with results read by your cell phone.
* Only microBIOMETER® identified soil health in a U. of Tennessee study of soil health test methods including Cornell, USDA, Alabama and other soil health panels costing ten times as much.
* There are >2 million academic articles that use microbial biomass laboratory tests as proof of soil health. However, lab tests cost $100 – $500. microBIOMETER® takes 20 minutes at an average of $10/test.
* Soil microbes quickly die when removed from the soil. microBIOMETER® reveals the microbial biomass of your soil as it exists. Lab tests use dried soil and we have demonstrated that 80% of microbes die upon drying.
* The low cost and simplicity of microBIOMETER® means you can use it to monitor what is happening in time to make necessary corrections.
* microBIOMETER® can tell you if you are increasing your soil organic carbon. For instance, an increase in microbial biomass of 100 ug MBC/g per acre of agricultural land is equal to an elephant’s weight in microbial biomass, which is about 400 lbs of microbial carbon or >1450 lbs of CO2 equivalents. This can be accomplished by switching from heavy chemical fertilizer use to regenerative practices.
microBIOMETER® helping increase soil health in Brazil.Marcelo Chiappetta of Chiappetta Agricultural Company in Brazil shared with us how microBIOMETER® is assisting them with their soil management efforts. Their main agricultural crops are soybeans and corn. Between those crops, as they have a temperate climate during the winter months in southern Brazil, is the possibility of growing a cover crop mixture of radish, vetch, rye, and oats and feeding the soil with different roots.
Analyzing your fungal to bacterial ratio data.
We receive this question often and the answer is no.
How do we know this? microBIOMETER® shows that soil removed from the earth and plants lose microbial biomass every day which we have confirmed with microscopic studies. The literature also confirms this.
Why is there confusion? Most of the microbes in soil are in the “dormant” state, they only wake up when stimulated by the plant or some other stimulus. For a long time people thought dormant microbes were dead. Now we know they have lost as much water as possible and encased themselves in a tough cocoon that can allow them to survive for up to thousands of years. microBIOMETER® measures these earth-colored dormant microbes.
What microbes are dormant? All soil microbes have the ability to go dormant. This allows them to survive drought, freezing, starvation, etc. Bacteria and fungi build tough spore walls to protect themselves. microBIOMETER® measures those spores.
In the winter when it is below freezing in New York, if we microscopically examine the microbes that are separated from soil using microBIOMETER® we see very few fungi but plenty of spores. In spring the arbuscular mycorrhizal fungi spores will germinate and find a plant to colonize. In the Fall when roots are dying and decaying organic matter is present in the soil, we see a profusion of the saprophytic fungi that break down the tough vegetable matter. Bacteria can sporulate but even the bacteria that do not sporulate manage to wrap themselves in a tough outer coat by collecting clay and minerals in their gluey outer biofilm.
For more information on fungal spores, please visit mycorrhizas.info.
Soil microbes are tightly bound to and often covered in soil making them very hard to evaluate by microscopy. The special magic of microBIOMETER® is the extraction powder and whisking process that separates most of the microbes from the soil. And during the 20 minute settling time allows the soil particles to precipitate leaving the extraction fluid >95% microbial.
This allows microBIOMETER® to examine 100 – 1000 times more microbes than any other method. When you apply extraction fluid to the membrane in the test card the colored microbes are captured on the surface of the membrane. A cell phone picture of the card is analyzed by the app and the intensity of the color of the microbes indicates their quantity – this is the basis for all laboratory colorimetric tests. We discovered that the fungi in soils are a slightly different color than bacteria, and so the app is able to distinguish between bacteria and fungi.
Click here to see a full video tutorial of microBIOMETER® soil testing.
Arbuscular mycorrhizal fungi (AMF) penetrate the root and establish little areas in plant root cells where they can exchange nutrients with the plant. AMF improves the nutrients available to the plant by collecting soil minerals such as phosphorous, nitrogen, magnesium and manganese through an extensive network of fine fibers (hyphae) that increase the absorptive area of the root up to a hundred-fold. In return the plant feeds the fungi carbohydrates and lipids. AMF secrete hormone like substances that stimulate plant growth and AMF encourages the establishment of nitrogen fixing bacteria. The AMF boost to plant growth comes not only from the nutrients it supplies. AMF also improves the immune response of plants making them resistant to harmful nematodes and insects as well as fungal and bacterial pathogens.
AMF shows great promise in compensating for yield losses when chemical fertilizers are eliminated or greatly reduced. AMF can reduce the need for pesticides and phosphate and nitrogen fertilizers cutting back on input costs all while building healthier soil.
In light of the known importance AMF plays in your plant’s health, microBIOMETER® now provides the fungal to bacterial ratio of your soil. This information will further assist you on your road to healthy soil while helping you lower your costs.
Leifheit, E. F., Veresoglou, S. D., Lehmann, A., Morris, E. K., & Rillig, M. C. (2014). Multiple factors influence the role of arbuscular mycorrhizal fungi in soil aggregation—a meta-analysis. Plant and Soil, 374(1-2), 523-537.
Understanding Soil Organic Matter and its impact on soil health and microbial biomass.
We are often asked what is a good level of microbial biomass (MB). There is no one answer. The level of MB you can reach is dependent on soil organic matter (SOM.) Soil organic carbon (SOC) is a large part of soil organic matter but SOM is a mixture of Carbon (C), Nitrogen (N), Phosphorus (P), Sulfur (S) and all the other minerals that microbes and plants need.
There are 2 types of SOM: Stable SOM, often referred to as humic matter; and Fresh SOM. Fresh SOM is composed of SOM material recently released from Stable SOM and any fertilizers, amendments or litter. You can compensate for low stable SOM by providing lots of fresh SOM. The key to the efficacy of fresh SOM is that it needs to be nutrient balanced*, i.e. it needs the correct balance of C,N,P, and S. That is where understanding soil chemistry and using the right additives comes in.
Think of SOM as your credit reserve. In spring, the plant starts to grow and puts out exudates that stimulate the microbes to multiply. But these multiplying microbes need more than the sugars that the plant supplies, they need the N, P, S and micro nutrients that are in SOM.
Agronomists often cultivate soil for intensive organic agriculture and those soils contain lots of fresh organic matter. The microbial biomass of these mixtures can read as high as 2000 ug MBC/gram of dry soil. As the microbes and plants in this rich soil die, they become fresh SOM. The amount of stable SOM that soil can store depends to a large degree on the type of soil because storage requires mineral surfaces for attachment and aggregates for protection. If your soil is inherently poor at storing SOM, you will need to rely on fresh SOM to feed your microbes and plants.
We highly recommend that you read the review referenced below to better understand SOM.
Coonan, E.C., Kirkby, C.A., Kirkegaard, J.A. et al. Microorganisms and nutrient stoichiometry as mediators of soil organic matter dynamics. Nutr Cycl Agroecosyst 117, 273–298 (2020). https://doi.org/10.1007/s10705-020-10076-8
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