Don’t Spoil the Soil

I haven’t written in quite some time, because I’ve been digging into additional topics, soil being one. I have been venturing down a broader path of interest, which still relates back to bees, as healthy soil enhances their resources above ground. Soil is a universe that many of us never contemplate, as it is unseen, beneath our feet, not where our eyes are generally focused. It carries a web of life that, when untouched by our ideas of land management, brilliantly supports the health and longevity of plants that our eyes do connect with, which supports the wildlife we also admire.

IMG_5310Under one step taken in the forest, there is up to 300 miles of fungal strands!

What is soil? Isn’t it synonymous with dirt? Soil is teeming with life! Dirt is dead, and is what results in overgrazing, over farming, over tilling, over spraying with unnecessary chemicals, and does not adequately support any plant life on its own. Dirt requires chemical inputs to support plant life; healthy soil does not.

The soil food web begins with a healthy supply of roots. Plants photosynthesize to build stems, roots, leaves, and blooms. In the process of photosynthesis, sugars and oxygen are produced. Some sugars are released from the roots, as well as delivered to nectaries (sugar water producing organs) of the plant. The sugars released by root systems are called exudates. Exudates are food for many players in the soil food web. We will begin with microbes; the bottom of the food chain. Microbes (bacteria and fungus) feed on the exudates and organic matter from decaying debris. In exchange for the exudates, they unlock inaccessible (Nitrogen and Phosphorus) nutrients for plants to use in building new cells and growing.

IMG_5294In one teaspoon of healthy soil there can be over 1 billion bacteria!

Bacteria form a wall along the outside of roots, awaiting their foods (exudates) like pigs at a feeding trough. This wall serves as a barrier, protecting the roots from threats that could be lurking in the surrounding soil. The diversity of bacteria surrounding root systems is very important, as not all bacterial species are active under the same conditions and soil conditions are very dynamic. Oxygen reliant bacteria, the aerobic variety, need oxygen. They inhale the oxygen and exhale carbon dioxide, which means they need a place to do this. Bacteria build small chambers around themselves to capture oxygen, thus aerating the soil, and creating soil structure. This not only creates pockets for oxygen and carbon dioxide exchange, but also places for water to infiltrate, thus increasing water retention around the roots. Another variety of bacteria (nitrogen fixing) will live inside nodules formed along the roots of legumes, fixing nitrogen, which makes it accessible to plants. The world of soil bacteria is large and complex, and my blog post could never do it justice. This is a very simple explanation of the complex partnerships between soil bacteria and plants, but an intriguing start, don’t you agree?

Fungus, of the mycorrhizal variety, stretches across root systems, forming a web of interconnections between plants. This facilitates communication between plants via roots and fungal highways (mycelium) composed of thousands of individual fungal cells called hyphae. This fungal network comes at a price of 1/3 of the plant’s exudates! This is expensive, but worth it. Fungus also plays a significant role in decomposing dead plant and animal debris, thus unlocking nutrients for the plant’s use. Mycelium networks transport messages of distress, nutrients to be shared with other plants, and can offer defense against threats to the plant, including undesirable species of nematodes, by choking them with built in lassos. Not all fungi are in the soil, working in symbiosis with plants. Some work to digest living and dead plant material, if given the right conditions, which is not always beneficial to the plant. This isn’t to say that these fungi should be eliminated, they just serve a different purpose, which is undoubtedly irreplaceable to other pieces in the overall ecosystem web.

IMG_4207Mushrooms are the fruiting bodies (reproductive organ) of fungus.

A food web isn’t complete without predators. Predators, nematodes (unsegmented worms) and protozoa (ciliates, flagellates, amoebas), assist in unlocking nutrients for plants by ingesting microbes (bacteria and fungus).

Look closely and you’ll see protozoa working away at breaking up plant debris, which has loads of microbes clinging to it. When you see movement, those are protozoa. Toward the end, you’ll see a nematode too! This is footage of a sample of the forest floor. Unfortunately, my microscope isn’t powerful enough to see individual fungal strands and bacteria.

The soil food web is a passing of the baton from one food group to the next, unlocking different foods for plants to use through their root systems. Nutrients are found in their waste, and unlocked when they die. As we progress up in the food chain, there are arthropods, otherwise known as shredders, who grind up dead plant debris along the surface of soil; they too may partake in ingesting microbes. Earth worms are another contributor to soil health. They ingest dead plant and animal debris as they tunnel through soil (aerating along the way), pooping their black gold adjacent to root systems (fertilizing), offering a wealth of nutrients for plants. Some worms tunnel vertically, grabbing dead plant debris from the surface and dragging it down, deep into the soil. In a sense they are kneading the soil’s ingredients by turning in fresh foods from up top. Other worms will tunnel horizontally, eating and pooping along the way. Of course, all of these predators have predators, mammals and birds. If the soil food web is teeming with life, mammals and birds will show up for the buffet. Their waste becomes more nutrients for the soil food web, and a spinning wheel of life is in place. It’s a thing of beauty!

IMG_4516Mama wren found some good grub in the yard!

This is a lot of info condensed into a very short summary, but what does it mean to you and your yard? The application of this information is simple; it reduces work from you over time. When all the elements of soil are in place, and working together to pass nutrients back and forth to each other, there is no need for our inputs. No need to spend money on synthetic fertilizers, fungicides, insecticides, or any other manmade fix for acute problems. In fact, using such things can reinforce your dependence on them. Recent studies have demonstrated that addition of nitrogen will impact the diversity and population count of soil bacteria (LINK). If soil bacteria populations decrease in diversity, nutrients those populations provide will need to be added back to the system. If we leave it alone, and allow the natural balance to be restored, our yards will become spinning wheels of life. It will be time to pull out the lawn chair, sit back, relax, and enjoy the bounty of getting out of nature’s way.

Healthy soil consists of billions of important players, and each one is important. The system is astonishing in its’ perfect interconnected balancing act. Is the system absent of all problems? No, but it will be independently functional, and fully capable of maintaining a reasonable level of those imperfections, meaning nothing will overtake the system, and move it out of balance, so long as all pieces are allowed to thrive.

So, how do we foster a healthy soil food web in our own yards? 

  1. Stop using synthetic fertilizers. Consider mixing in cover crops and dynamic accumulators (plants that bring nutrients into the top soil) such as clover, buckwheat, oats, millet, and many others. The resources for choosing which ones to use are readily available when you search the topic. HERE is a wonderful article on the topic of using cover crops to improve soil health. Compost is another way to increase the health of your yard’s soil. You could even add animal waste, which can make people a little squeamish, but chicken poop is some of the best soil feeders!
  2. Refrain from using any pesticides whatsoever. Pesticides include insecticides, herbicides, fungicides, etc. None of them do any service to our yards and small gardens. In fact, they reduce the amount of garden helpers, the ones that predate on pests, pollinate flowers and food producing plants, and it is terrible for songbirds too. We do not need them! Why waste the money on them? Instead, allow the system to fix the imbalances over time.
  3. Plant with diversity as the top priority in your annual planning, whether you are planting perennials or food crops. When selecting perennials, consider native as the top priority, with plants that are tolerant of your climate second, and never to include exotics to your region. This approach targets native wildlife to your yard, conserves water usage, and fuels the soil more efficiently. With your food crops, rotate what you are growing in each plot to reduce pest load. Diversity in general invites diversity, meaning, diverse plants attracts diverse animals. This leads to a balanced population of predators and pests, and keeps the problems at a minimum over time.
  4. Don’t till the soil in your annual beds, or yard, and never leave ground bare of any roots. Tilling disrupts the soil food web network! If you are done growing food, consider filling that bed with clover (or a mix of cover crops) heading into the winter. When that clover lays down on the soil, it will release nitrogen into that soil, preparing it for the next growing season. The roots of that cover crop will also continue feeding the soil food web, thus maintaining that vibrant plant support for the next growing season.

The more I learn about the world around me, the more I am blown away by how interconnected everything really is. This motivates me to continue learning and sharing the lessons along the way. Bees got me started, and nature continues to inspire me to learn. I am not finished studying my favorite buzzing muses, but expanding my understanding of the greater jigsaw puzzle they toil within. After all, the way we treat the soil beneath our feet must have some amount of impact on the bees who nest and develop there.

IMG_3571Melissodes bimaculatus-digger bee. She’s loaded with white pollen to bring back to her underground nesting tunnel. 

Thank you for joining the movement with me. I will be posting a list of resources for those of you who are reading to dig deeper with me on the topic of soil! Keep your eyes peeled. Until then, get outside and look at what miracles are taking place in your yard. Please LIKE, and SHARE this post, if you found it useful. This expands our reach;)