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The Living Earth: What Is Actually Happening Beneath Our Feet? · Old Ways New Days

0:00
SPEAKER_00: There is a moment in every garden when the world seems to go quiet.
0:04
SPEAKER_00: The sun has slipped behind the trees, the last bees are disappearing among the flowers.
0:10
SPEAKER_00: The leaves of the tomato plants hang heavy with the day's heat, and somewhere beneath the beans and squash, beneath the weeds grown along the fence, beneath the roots of the trees lining the street, another world is carrying on with its work.
0:26
SPEAKER_00: It is a world we rarely see.
0:28
SPEAKER_00: We walk across it, we dig into it, we plant seeds in it, we pull weeds from it.
0:34
SPEAKER_00: Sometimes we complain about it, especially when it clings to our boots or refuses to drain after a heavy rain.
0:42
SPEAKER_00: We call it dirt.
0:45
SPEAKER_00: But imagine for a moment that you could shrink yourself small enough to travel between the grains of sand and clay.
0:53
SPEAKER_00: Imagine slipping into the tiny spaces between soil particles, where water gathers in delicate films and air.
1:02
SPEAKER_00: Imagine discovering threads so fine that you can barely see them stretching through the earth like an underground network.
1:10
SPEAKER_00: Imagine bacteria breaking down organic, fungixing through the soil, microscopic predators feeding on other organisms, and earthworms pulling to leaves into their tongues.
1:24
SPEAKER_00: Imagine roots releasing sugars into a surrounding soil, feeding organisms that in turn help make nutrients available to the plants above.
1:34
SPEAKER_00: And imagine that this activity isn't happening in one special garden or one untouched forest.
1:42
SPEAKER_00: It's happening beneath your feet, in a backyard, under a community garden, in the soil beneath a city park, in a field of corn, in a patch of weeds growing through a crack in the pavement, even in the soil of a neglected lot.
1:58
SPEAKER_00: Life is trying to make a home.
2:01
SPEAKER_00: The earth beneath us isn't simply a place where plants are meant filled with relationships, exchanges, competition, cooperation, decomposition, and renewal.
2:15
SPEAKER_00: And when we begin to understand that, we start to look at our gardens differently.
2:20
SPEAKER_00: A handful of soil becomes more than something to scoop into a pond.
2:24
SPEAKER_00: A fallen leaf becomes more than yard waste.
2:27
SPEAKER_00: A worm becomes more than a creature we find after the rain.
2:32
SPEAKER_00: And a patch of bare ground becomes something worth thinking about.
2:37
SPEAKER_00: Because the question isn't simply whether our soil can hold a plant upright.
2:41
SPEAKER_00: The question is whether we're creating the conditions that allow the living world beneath that plant to function.
2:48
SPEAKER_00: Today we're going underground.
2:50
SPEAKER_00: We're going to explore the organisms that make soil alive, the role of fungi and bacteria, the work of earthworms, the importance of organic matter, and the complicated processes through which nutrients move from one part of an ecosystem to another.
3:06
SPEAKER_00: We'll talk about microzoil relationships, soil structure, compaction, and why adding fertilizer isn't the same thing as building healthy soil.
3:16
SPEAKER_00: And we'll finish with practical ways to care for the soil in your own garden, whether you have a large homestead, a small backyard, a raised bed, or a few containers on a balcony.
3:26
SPEAKER_00: Because if season one taught us how important it is to grow food, season two is going to help us understand the systems that make food possible.
3:36
SPEAKER_00: Welcome to the living earth, what is actually happening beneath our feet?
3:40
SPEAKER_00: Welcome back to Old Ways, New Days, where the old ways meet the good dirt.
3:44
SPEAKER_00: I'm Kayla, and this will be a solo episode today.
3:48
SPEAKER_00: So, due to a scheduling issue, mostly on my part, um, Nell could not make it because I am recording very late Wednesday night for Thursday's episode.
4:03
SPEAKER_00: So we're gonna begin with uh explaining why soil is not simply dirt.
4:09
SPEAKER_00: Uh that is a distinction that might sound obvious, but matters more than we realize.
4:14
SPEAKER_00: Soil and dirt are not quite the same thing.
4:17
SPEAKER_00: In everyday conversation, we use the words interchangeably.
4:22
SPEAKER_00: We stay we say we have dirt on our shoes, dirt beneath our fingernails, or dirt on the kitchen floor.
4:30
SPEAKER_00: But soil is a much more complex system.
4:34
SPEAKER_00: Soil contains mineral particles, organic matter, and a delta who is getting into things she should.
4:42
SPEAKER_00: Hey baby girl! Excuse me, listeners, while I move the kitty.
4:48
SPEAKER_00: Come here, baby.
4:51
SPEAKER_00: I'm gonna speak up so everyone can hear you.
4:55
unknown: Alright.
4:59
SPEAKER_00: As I was saying, soil contains mineral particles, organic matter, water, air, and living organisms.
5:07
SPEAKER_00: Those components interact to create an environment that supports plant growth and performs essential functions throughout the wider ecosystem.
5:15
SPEAKER_00: The mineral portion comes from the breakdown of rocks and other geological material.
5:21
SPEAKER_00: Organic matter comes from living things and the remains, dead roots, fallen leaves, plant residues, animal remains, and the substances produced as organisms live and decompose.
5:35
SPEAKER_00: Water moves through spaces between soil particles.
5:40
SPEAKER_00: Air occupies some of those spaces, supplying oxygen to roots and organisms that need it.
5:46
SPEAKER_00: And living organisms transform, consume, transport, and recycle materials throughout the system.
5:52
SPEAKER_00: The proportions of these components vary from place to place.
5:56
SPEAKER_00: A sandy soil behaves differently from a clay soil.
6:00
SPEAKER_00: A woodland soil rich in decomposing leaves differs from a heavily disturbed construction site.
6:06
SPEAKER_00: A garden bed that's been receiving organic matter for years may behave differently from a new bed filled with poorly structured subsoil.
6:18
SPEAKER_00: Delta.
6:19
SPEAKER_00: Alright, the kitty is going to drive me nuts tonight.
6:30
SPEAKER_00: These differences matter because soil isn't just a physical substance, it's an environment.
6:42
SPEAKER_00: There is an empty box in the office.
6:48
SPEAKER_00: The USDA Natural Resources Conversation Service describes soil health as the USDA Natural Resources Conservation Services describes soil health as the continued capacity of soil to function as a vital living ecosystem that sustains plants, animals, and humans.
7:10
SPEAKER_00: That definition gets to the heart of what we're discussing today.
7:14
SPEAKER_00: Healthy soil does more than support a harvest.
7:17
SPEAKER_00: It helps regulate water, cycles nutrients, filters substances, provides habitat, and supports plant growth.
7:25
SPEAKER_00: Think about the difference between a pot filled with inert growing material and a healthy garden soil.
7:30
SPEAKER_00: Both may physically support a plant.
7:33
SPEAKER_00: But healthy soil can also contain a complex community of organisms interacting with roots, breaking down organic materials, and changing the availability of nutrients.
7:44
SPEAKER_00: That living activity is one of the reasons soil can sustain a garden over time.
7:50
SPEAKER_00: And it's why building healthy soil is not quite the same thing as buying a bag of fertilizer.
7:56
SPEAKER_00: Fertilizer can supply nutrients.
7:59
SPEAKER_00: Compost can add organic matter and nutrients, and mulch can protect the surface.
8:05
SPEAKER_00: But the long-term health of a garden also depends on how we manage the living system that surrounds the roots.
8:12
SPEAKER_00: We aren't just filling a container, we're creating a habitat.
8:17
SPEAKER_00: So let's meet some of the inhabitants.
8:20
SPEAKER_00: When we talk about soil life, we often imagine earthworms, because they're easy to see.
8:26
SPEAKER_00: But earthworms are only one part of a much larger community.
8:31
SPEAKER_00: Soil contains bacteria, fungi, microscopic animals, nematodes, protozoa, arthropods, and many other organisms.
8:40
SPEAKER_00: Their abundance and activity vary with soil conditions, climate, vegetation, moisture, and management.
8:47
SPEAKER_00: Together, these organisms participate in what scientists call the soil food web.
8:54
SPEAKER_00: A food web describes how energy and materials move between organisms through feeding relationships.
9:01
SPEAKER_00: Leaves fall, microorganisms begin breaking them down.
9:05
SPEAKER_00: Small organisms feed on those microorganisms.
9:08
SPEAKER_00: Other organisms feed on those.
9:11
SPEAKER_00: Dead organisms become resources for still more organisms.
9:16
SPEAKER_00: And throughout these relationships, nutrients are transferred and recycled.
9:25
SPEAKER_00: It's an interconnected network.
9:28
SPEAKER_00: Some organisms consume dead plant material.
9:31
SPEAKER_00: Others feed on bacteria or fungi.
9:34
SPEAKER_00: Some are predators.
9:35
SPEAKER_00: Some live in close association with plant roots.
9:39
SPEAKER_00: Relationships benefit plants directly.
9:43
SPEAKER_00: Others contribute more indirectly by changing the physical and chemical conditions of the soil.
9:49
SPEAKER_00: And not every organism is beneficial in every situation.
9:53
SPEAKER_00: Some microorganisms cause plant diseases.
9:57
SPEAKER_00: Some compete with plants for nutrients, and some consume roots or damage seedlings.
10:04
SPEAKER_00: The goal of healthy soil management isn't to make every organism beneficial.
10:10
SPEAKER_00: That's impossible.
10:12
SPEAKER_00: The goal is to support a diverse, functioning ecosystem with the conditions needed for healthy plant growth and nutrient cycling.
10:19
SPEAKER_00: A diverse soil community can help create a more balanced system, although diversity alone does not guarantee that pests or disease will never occur.
10:30
SPEAKER_00: So when we talk about feeding the soil, we're talking about supporting a community, not simply feeding the plant.
10:36
SPEAKER_00: And that brings us to some of the smallest but most influential residents of the garden.
10:44
SPEAKER_00: Bacteria.
10:46
SPEAKER_00: Bacteria are everywhere in healthy soil.
10:49
SPEAKER_00: They are microscopic organisms, generally consisting of a single cell, and they perform a remarkable variety of jobs.
10:57
SPEAKER_00: Some break down easily decomposed organic materials, some participate in the cycling of carbon, nitrogen, sulfur, and other elements.
11:07
SPEAKER_00: Some live close to plant roots and interact with the plants growing above them.
11:12
SPEAKER_00: Others participate in processes that affect the availability of nutrients, the chemistry of the soil, and the growth of other organisms.
11:21
SPEAKER_00: Let's focus on decomposition.
11:24
SPEAKER_00: When a leaf falls from a tree, it doesn't disappear.
11:27
SPEAKER_00: It begins a process of transformation.
11:30
SPEAKER_00: Depending on the leaf, the environmental conditions, and the organisms present, different compounds break down at different rates.
11:38
SPEAKER_00: Bacteria use certain organic compounds as sources of energy and materials for growth.
11:44
SPEAKER_00: As they consume and transform those compounds, they release substances into the surrounding environment.
11:55
SPEAKER_00: Some are incorporated into microbial biomass, some are released as carbon dioxide during respiration.
12:03
SPEAKER_00: Other organisms then feed on bacteria, or the bacteria themselves die and become part of the organic material available to the rest of the soil community.
12:12
SPEAKER_00: This is one of the many ways nutrients move through the soil food web.
12:18
SPEAKER_00: Bacteria also participate in the nitrogen cycle.
12:29
SPEAKER_00: Nitrogen is essential for plant growth, but plants cannot simply use every form of nitrogen present in the environment.
12:38
SPEAKER_00: Different microorganisms transform nitrogen compounds through processes such as decomposition, mineralization, nutrification, and denetrification.
12:50
SPEAKER_00: Certain bacteria can also convert atmospheric nitrogen into forms that enter biological systems through a process called nitrogen fixation.
12:58
SPEAKER_00: Some of these bacteria form partnerships with particular plants, including many legumes.
13:04
SPEAKER_00: You've probably seen this relationship if you've examined the roots of beans or peas.
13:10
SPEAKER_00: Sometimes you can find small nodules attached to the roots.
13:14
SPEAKER_00: Those nodules can house nitrogen-fixing bacteria that receive energy from the plant and help convert atmospheric nitrogen into a biologically useful form.
13:24
SPEAKER_00: This relationship is one reason legumes are often included in crop rotations and cover crop mixtures.
13:33
SPEAKER_00: But there's an important detail here.
13:35
SPEAKER_00: Growing beans doesn't mean that every bit of nitrogen fixed by the bacteria immediately becomes available to every plant nearby.
13:42
SPEAKER_00: Nitrogen moves through the system in different forms.
13:46
SPEAKER_00: Some remain in the plant, some enter the soil when roots and residues decompose, and some can be lost from the system.
13:54
SPEAKER_00: The benefit depends on the crop, its growth, soil condition, and what happens to the plant afterward.
14:01
SPEAKER_00: That's why a cover crop grown for soil improvement needs to be managed appropriately if you want to capture its full value.
14:09
SPEAKER_00: And bacteria aren't the only organisms involved in these transformations.
14:14
SPEAKER_00: Fungi, earthworms, other soil animals, plant roots, and physical processes all contribute.
14:21
SPEAKER_00: The lesson is that nutrients aren't simply sitting on the ground waiting for us to add water.
14:26
SPEAKER_00: They're part of a moving, changing system.
14:30
SPEAKER_00: Now let's talk about fungi.
14:33
SPEAKER_00: If bacteria are some of the tiny transformers of the soil, fungi are among the organisms that can create extensive networks through it.
14:42
SPEAKER_00: Many fungi grow as fine, thread-like structures called hyphaea.
14:49
SPEAKER_00: A massive network of these hyphaea is called a mycelium.
14:53
SPEAKER_00: If you've ever lifted a piece of damp, decomposing wood and noticed delicate white threads spreading through it, you may have seen fungal mycelium.
15:03
SPEAKER_00: Similar networks can occur in soil, although many are too fine to notice without close examination.
15:09
SPEAKER_00: Fungi play several important roles.
15:12
SPEAKER_00: Some break down plant material, including compounds that can be difficult for other organisms to decompose.
15:18
SPEAKER_00: Some help build or stabilize soil aggregates through their physical growth and the substance they produce.
15:26
SPEAKER_00: Some form partnerships with plant roots.
15:28
SPEAKER_00: Others are pathogens, parasites, or predators.
15:32
SPEAKER_00: Once again, fungi aren't all doing the same job, but some of their relationships with plants are particularly fascinating.
15:41
SPEAKER_00: Imagine a plant root growing through the soil.
15:44
SPEAKER_00: The roots can absorb water and dissolve nutrients from the soil immediately around it, but its reach is limited to the root's size, the surrounding soil conditions, and the distribution of available resources.
15:57
SPEAKER_00: Now imagine a network of fungal threads extending outward from that root.
16:01
SPEAKER_00: Some fungi form associations that allow fungal hyphae to explore soil beyond the immediate root surface.
16:09
SPEAKER_00: In suitable conditions, that network can help a plant access nutrients and water from a larger volume of soil than the root could explore alone.
16:19
SPEAKER_00: In return, the plant supplies the fungus with carbon compounds produced through photosynthesis.
16:26
SPEAKER_00: It's an exchange.
16:27
SPEAKER_00: The plant captures sunlight and uses it to build sugars and other carbon-rich compounds.
16:33
SPEAKER_00: Some of that carbon reaches the roots and is made available to associated microorganisms.
16:38
SPEAKER_00: The fungus receives a source of energy.
16:41
SPEAKER_00: The plant may receive improved access to certain nutrients and in some situations water.
16:47
SPEAKER_00: The precise benefits depend on the plant, the fungal partner, soil conditions, and availability of resources.
16:54
SPEAKER_00: This relationship can be especially important for many plants in natural ecosystems, and it gives us a different way of thinking about gardening.
17:02
SPEAKER_00: A plant isn't necessarily functioning as an isolated individual.
17:07
SPEAKER_00: Its roots exist within a community, and the soil surrounding those roots can influence how well the plant accesses water and nutrients.
17:19
SPEAKER_00: I now have two kitties in this room.
17:24
SPEAKER_00: The specific partnership between certain fungi and plant roots is called a microhoisal association.
17:33
SPEAKER_00: The word refers to a relationship between a fungus and a plant root.
17:38
SPEAKER_00: Many plants form microho micorizal associations, although not all plants do, and not every plant forms the same kind of association.
17:49
SPEAKER_00: Some plants are strongly dependent on these relationships and natural conditions.
17:53
SPEAKER_00: Others can grow without them under certain circumstances.
17:59
SPEAKER_00: In one common type called arbuscular mycorrozi, the fungus forms specialized structures within the root's tissues and extends hyphae out into the surrounding soil.
18:15
SPEAKER_00: Other types, such as ectomycorozi, form different structures around and between root cells and are common among many tree species.
18:29
SPEAKER_00: Different fungi associate with different groups of plants.
18:33
SPEAKER_00: So when we hear about a single underground fungal network connecting an entire forest, we need to be careful not to imagine every plant connected to one universal system.
18:43
SPEAKER_00: Real soil relationships are more complex than that, but the underlying principle is still remarkable.
18:50
SPEAKER_00: Plant roots and fungi can form partnerships that influence nutrient uptake, soil processes, and plant responses to environmental conditions.
18:59
SPEAKER_00: And this brings us back to a practical question.
19:02
SPEAKER_00: Can gardeners encourage mycorrhizal relationships?
19:08
SPEAKER_00: In many cases, yes, by supporting the conditions that help soil organisms thrive.
19:14
SPEAKER_00: That means avoiding unnecessary disturbance, growing plants suited to the site, maintaining living roots when practical, and building a diverse planting system.
19:25
SPEAKER_00: It does not mean every garden needs a commercial mycorrhizal inoculant.
19:31
SPEAKER_00: Products marked as beneficial fungi vary in composition and quality, and adding them doesn't guarantee improved plant growth.
19:39
SPEAKER_00: If a suitable fungal community is already present, introducing more fungi may provide little benefit.
19:46
SPEAKER_00: And the most reliable starting point is to improve the growing conditions and avoid practices that unnecessarily damage soil structure and biological habitat.
19:57
SPEAKER_00: And remember, mycorrhizal fungi are not a replacement for basic plant care.
20:02
SPEAKER_00: They cannot compensate for a plant growing in unsuitable conditions, severe nutrient deficiencies, or chronically waterlogged soil.
20:11
SPEAKER_00: They are one part of a much larger system.
20:17
SPEAKER_00: Now, for underground residents, most of us recognize earthworms.
20:22
SPEAKER_00: If you've ever turned over a patch of garden soil after rain and found earthworms wriggling away from the light, you know how quickly they can disappear.
20:31
SPEAKER_00: But what are they actually doing down there?
20:34
SPEAKER_00: Earthworms consume organic material and soil, depending on the species and their ecological habitats.
20:43
SPEAKER_00: As materials move through their digestive system, it is processed and deposited as castings.
20:49
SPEAKER_00: Earthworm activity can influence nutrient availability, soil aggregation, water movement, and the movement of organic matter through the soil profile.
20:58
SPEAKER_00: Some earthworms create burrows that improve pathways for air and water.
21:03
SPEAKER_00: Others live close to the surface and process leaf litter and other organic materials.
21:09
SPEAKER_00: Different species occupy different ecological roles.
21:13
SPEAKER_00: In a suitable garden, earthworms can be a useful sign that conditions support certain forms of soil life, but the number of earthworms you see isn't a complete measure of soil health.
21:24
SPEAKER_00: Some healthy soils naturally contain few earthworms, especially in certain climates or ecosystems.
21:31
SPEAKER_00: And in some forest environments, introduced earthworms can alter natural soil processes and damage habitats that evolved with very few or no earthworms.
21:41
SPEAKER_00: So we shouldn't assume that more earthworms are always better everywhere.
21:45
SPEAKER_00: In a home garden, however, earthworms are often beneficial participants in the decomposition and soil structure processes we want to encourage.
21:55
SPEAKER_00: So, how can we support them?
21:58
SPEAKER_00: We can support them by providing.
22:00
SPEAKER_00: In suitable organic material, avoid repeatedly disturbing the soil without a good reason, and prevent unnecessary compaction.
22:09
SPEAKER_00: Maintain appropriate moisture and be thoughtful about the products we apply.
22:14
SPEAKER_00: Remember that earthworms need a suitable environment, not just a pile of food.
22:19
SPEAKER_00: If the soil becomes extremely dry, waterlogged, or compacted, earthworms and other soil organisms may struggle.
22:26
SPEAKER_00: And please don't feel that you need to buy earthworms and release them into every garden bed.
22:32
SPEAKER_00: Many gardens already contain suitable earthworm populations.
22:36
SPEAKER_00: If yours doesn't, the best first step is to improve the soil habitat and understand the conditions in your garden.
22:45
SPEAKER_00: Let's talk next about organic matter.
22:49
SPEAKER_00: This is one of the most familiar terms in gardening, but it does deserve a closer look.
22:55
SPEAKER_00: Soil organic matter includes living organisms, recently dead plants and animal material, and more transformed organic substances produced as decomposition proceeds.
23:07
SPEAKER_00: In everyday gardening, when we talk about adding organic matter, we're often referring to compost, decomposed leaves, plant residues, or other suitable materials.
23:18
SPEAKER_00: Organic matter can help improve soil structure, it can influence water retention, it provides resources for soil organisms, and it plays an important role in nutrient cycling.
23:30
SPEAKER_00: But organic matter isn't a single substance, and different materials behave differently.
23:36
SPEAKER_00: Fresh grass clippings, woody chips, fallen leaves, finished compost, and decomposed manure all have different characteristics.
23:46
SPEAKER_00: Their nutrient content, carbon to nitrogen ratios, decomposition rates, and potential risks vary.
23:53
SPEAKER_00: This is why we need to think about how a material will affect function in the garden rather than assuming all organic material is interchangeable.
24:03
SPEAKER_00: And remember, compost is not magic dust.
24:07
SPEAKER_00: Compost can be an excellent addition to many garden soils.
24:10
SPEAKER_00: It can supply organic matter and some nutrients, and it can help improve soil structure over time.
24:16
SPEAKER_00: But compost isn't automatically the solution to every soil problem.
24:20
SPEAKER_00: If your soil has a serious drainage issue, a thin layer of compost may not fix it.
24:28
SPEAKER_00: If your soil has unsuitable pH for a particular crop, compost may not bring it into the correct range.
24:36
SPEAKER_00: If your garden already has excessive phosphorus from repeated compost or manure applications, adding more may worsen the imbalance.
24:45
SPEAKER_00: And if a product contains contaminants or hasn't been properly processed, it may introduce problems rather than solve them.
24:53
SPEAKER_00: For established garden beds, modest applications of suitable finished compost can be useful.
24:59
SPEAKER_00: For new beds, consider a soil test and the needs of the plants you're growing first.
25:05
SPEAKER_00: The aim is to build a soil that functions well, not simply to keep adding material indefinitely.
25:12
SPEAKER_00: The difference between organic matter and nutrients matters.
25:18
SPEAKER_00: Organic matter can contain nutrients, but it also affects the physical and biological properties of soil.
25:24
SPEAKER_00: You can have a soil with adequate nutrients that still has poor structure.
25:29
SPEAKER_00: You can have soil with good organic matter content, but an unstable pH.
25:34
SPEAKER_00: And you can have a garden bed with abundant compost that becomes too wet or too nutrient-rich for certain plants.
25:42
SPEAKER_00: Healthy soil management means understanding several factors together.
25:46
SPEAKER_00: That includes texture, structure, organic matter, pH, nutrient levels, drainage, and biological activity.
25:54
SPEAKER_00: A soil test can help answer questions about pH and nutrient status, while observation and simple field assessments can help you understand drainage, compaction, and soil structure.
26:05
SPEAKER_00: Use the right tool for the question that you're asking.
26:11
SPEAKER_00: Let's bring these pieces together.
26:13
SPEAKER_00: We've talked about bacteria, fungi, earthworms, and organic matter.
26:17
SPEAKER_00: Let's explore nutrient cycling.
26:21
SPEAKER_00: Plants need nutrients to grow.
26:23
SPEAKER_00: Nitrogen is essential for proteins and many other biological compounds.
26:28
SPEAKER_00: Phosphorus is involved in energy transfer and other cellular functions.
26:33
SPEAKER_00: Potassium plays important roles in water regulation and numerous physiological processes.
26:39
SPEAKER_00: Plants also need elements such as calcium, magnesium, sulfur, and several micronutrients.
26:46
SPEAKER_00: But these nutrients don't simply appear because a gardener wants them to.
26:50
SPEAKER_00: They move through biological and chemical processes.
26:54
SPEAKER_00: Let's follow that leaf again.
26:56
SPEAKER_00: That leaf that fell from a tree and landed on the ground, fungi, bacteria, and other organisms begin breaking down its tissues.
27:04
SPEAKER_00: Some of the leaf's carbon is used by organisms and eventually released through respiration.
27:09
SPEAKER_00: Some carbon enters microbial biomass or contributes to soil organic matter.
27:16
SPEAKER_00: Nutrients contained in the leaf can be released into the soil as decomposition proceeds.
27:22
SPEAKER_00: Other organisms consume the decomposers.
27:26
SPEAKER_00: Still more transformations occur.
27:28
SPEAKER_00: Eventually, some nutrients may become available for uptake by plant roots.
27:33
SPEAKER_00: A growing plant absorbs those nutrients, the nutrients become part of its leaves, stem, fruit, roots, and fruit.
27:42
SPEAKER_00: Later, a leaf falls again or the plant dies and the cycle continues.
27:47
SPEAKER_00: This is nutrient cycling.
27:50
SPEAKER_00: It doesn't mean that every nutrient is recycled perfectly or immediately.
27:55
SPEAKER_00: Some nutrients are lost through runoff, erosion, leaching, or gaseous processes.
28:00
SPEAKER_00: Some are locked in forms plants can't readily use.
28:05
SPEAKER_00: Some are removed when we harvest food and take it away from the garden.
28:10
SPEAKER_00: And some remain in organic matter until conditions allow them to be released.
28:15
SPEAKER_00: This is why gardening is not a perfectly closed system.
28:19
SPEAKER_00: When we harvest tomatoes, beans, squash, and other crops, we're exporting nutrients from the bed.
28:26
SPEAKER_00: If we repeatedly harvest food without replacing nutrients or returning suitable organic materials, the system may eventually become depleted.
28:35
SPEAKER_00: That's one reason composting can be valuable.
28:39
SPEAKER_00: Plant scraps and other suitable organic materials can return some nutrients and carbon to the garden.
28:44
SPEAKER_00: But composting doesn't create nutrients out of nothing.
28:49
SPEAKER_00: The nutrients and compost came from the materials used to make it, and if we remove all those materials from one location and add them to another, we're moving nutrients around rather than creating them.
29:02
SPEAKER_00: Understanding that helps us make better decisions about compost, fertilizer, crop residues, and food scraps.
29:09
SPEAKER_00: The goal is to manage the cycle thoughtfully.
29:14
SPEAKER_00: Now let's turn our attention to the physical structure of soil.
29:19
SPEAKER_00: So imagine filling a jar with sand.
29:21
SPEAKER_00: The particles settle and water can move through the spaces between them relatively quickly.
29:27
SPEAKER_00: Now imagine a fine textured clay soil.
29:30
SPEAKER_00: Its particles are much smaller, and its behavior can be very different.
29:35
SPEAKER_00: Real garden soils are mixtures of mineral particulates, organic matter, water, air, and biological materials.
29:44
SPEAKER_00: Their behavior depends on texture and structure.
29:48
SPEAKER_00: Now texture describes the relative proportions of sand, silt, and clay, while structure describes how soil particulates are arranged into aggregates or clumps and how those aggregates relate to the spaces between them.
30:06
SPEAKER_00: Good soil structure can create a balance of pore spaces.
30:15
SPEAKER_00: Anyway, pore isn't like the pores on your face.
30:18
SPEAKER_00: Some pores hold water.
30:21
SPEAKER_00: Others allow air to move through the soil.
30:24
SPEAKER_00: Some provide pathways for roots and organisms.
30:27
SPEAKER_00: This balance matters because roots need both water and oxygen.
30:32
SPEAKER_00: If soil remains waterlogged, air-filled spaces become limited and roots can struggle to function.
30:38
SPEAKER_00: If soil drains too rapidly and cannot retain enough water, plants may experience drought stress, even when rainfall seems frequent.
30:47
SPEAKER_00: Structure also influences how easily roots can penetrate the soil and how readily water infiltrates the surface.
30:55
SPEAKER_00: Healthy soil aggregates can help the soil resist erosion and maintain useful pore spaces.
31:01
SPEAKER_00: Organic matter, fungal hyphae, root activity, soil organisms, and physical properties of the mineral material all influence structure.
31:10
SPEAKER_00: This is one reason soil building is a long-term process.
31:14
SPEAKER_00: You can't always fix a structural problem by adding a single ingredient.
31:19
SPEAKER_00: Sometimes the most useful changes are repeated over time, protecting the soil surface, reducing unnecessary disturbance, adding suitable organic materials, growing roots, and preventing compaction.
31:32
SPEAKER_00: And sometimes the answer is to work with the soil you have rather than trying to turn it into something completely different.
31:44
SPEAKER_00: A heavy clay soil may never drain exactly like a sandy bed, but understanding the soil's properties helps you choose appropriate plants and management strategies.
31:57
SPEAKER_00: So let's talk about compaction.
31:59
SPEAKER_00: Compaction occurs when pressure pushes soil particulates closer together, reducing the size or number of poor spaces.
32:08
SPEAKER_00: This can happen when people repeatedly walk on garden beds with when heavy machinery travels over soil, when vehicles cross a planting area, or when soil is worked with excess while excessively wet.
32:22
SPEAKER_00: Compacted soil can resist restrict root growth, it can reduce infiltration, it can limit air movement, contribute to poor pooling on the surface or running off instead of entering the soil.
32:36
SPEAKER_00: And it can make it harder for soil organisms to move through the soil.
32:41
SPEAKER_00: Imagine trying to grow a carrot in loose soil compared with trying to grow one in dense, hard layers.
32:47
SPEAKER_00: The difference is obvious, but compacted soil can become a cycle of frustration.
32:54
SPEAKER_00: Water doesn't infiltrate well, plants struggle.
32:58
SPEAKER_00: The gardener tries to improve the soil by digging or tilling it.
33:01
SPEAKER_00: The soils worked while wet, or the same areas are repeatedly walked over.
33:06
SPEAKER_00: The problem returns.
33:08
SPEAKER_00: So what can we do?
33:10
SPEAKER_00: Keep feet off the growing beds, for one.
33:14
SPEAKER_00: One of the simplest strategies is to establish paths and avoid walking through the beds where crops grow.
33:21
SPEAKER_00: For a raised bed, design it so you can reach the center from the edges.
33:25
SPEAKER_00: For an in-ground garden, use permanent or clearly defined pathways.
33:30
SPEAKER_00: In a community garden, avoid walking on beds after heavy rain when the soil is particularly vulnerable to compaction.
33:38
SPEAKER_00: And don't work soil when it's wet.
33:41
SPEAKER_00: Wet soil can be especially vulnerable to compaction and structural damage.
33:46
SPEAKER_00: If soil sticks heavily into tools and smears rather than crumbling, it may be too wet to work.
33:53
SPEAKER_00: Wait until conditions improve.
33:57
SPEAKER_00: If compaction is shallow and localized, carefully loosening the affected area may help, but repeatedly digging deep through the whole garden isn't always the best answer.
34:08
SPEAKER_00: First, identify the depth and cause of the problem.
34:12
SPEAKER_00: If the compaction is severe or extends deeply, you may need a more targeted approach.
34:18
SPEAKER_00: In some situations, deep-rooted plants can help create biological channels over time, but they won't magically resolve every compacted layer.
34:27
SPEAKER_00: If you have a small garden, start by protecting the soil and improving how you move around it.
34:32
SPEAKER_00: Prevention is often easier than repair.
34:39
SPEAKER_00: The USDA Natural Resources Conservation Service emphasizes four central soil health principles.
34:46
SPEAKER_00: Minimize disturbance, maximize soil cover, maximize biodiversity, maintain living roots as much of the year as practical.
34:56
SPEAKER_00: These principles are intended to support the organisms and processes that make soil function.
35:02
SPEAKER_00: So let's translate that into some practical gardening choices.
35:07
SPEAKER_00: So, number one, disturb the soil less.
35:10
SPEAKER_00: This doesn't mean nobody should ever dig.
35:13
SPEAKER_00: Sometimes digging is necessary.
35:16
SPEAKER_00: You may need to prepare a new bed, plant a tree, remove an invasive plant, or address a particular soil problem.
35:24
SPEAKER_00: The principle is to avoid unnecessary disturbance.
35:28
SPEAKER_00: Repeated tilling can disrupt soil aggregates, fungal networks, and organism habitats.
35:33
SPEAKER_00: It can also leave soil more vulnerable to erosion and moisture loss.
35:38
SPEAKER_00: For a home gardener, that might mean loosening only the area that needs areas that need it, avoiding routine deep digging, and consider no-till or reduced till approaches where appropriate.
35:51
SPEAKER_00: You don't have to abandon every traditional gardening technique.
35:55
SPEAKER_00: You simply need to understand why you're using it and whether it's helping.
36:01
SPEAKER_00: So uh point number two, uh keep soil covered.
36:07
SPEAKER_00: Bare soil is exposed to the elements.
36:09
SPEAKER_00: Rain can dislodge soil particles, wind can carry them away, sunlight and heat can increase surface drying.
36:18
SPEAKER_00: A layer of suitable mulch can protect the soil surface, moderate temperature, reduce evaporation, and provide habitat for some soil organisms.
36:28
SPEAKER_00: Organic mulch, such as leaves, straw, and suitable plant residues, can also contribute organic matter as they decompose.
36:37
SPEAKER_00: But mulch choice matters.
36:39
SPEAKER_00: Some materials are better suited to particular crops or conditions.
36:44
SPEAKER_00: To avoid piling mulch directly against tree trunks or plant crowns where it could encourage rot or other problems.
36:51
SPEAKER_00: And if you use wood chips, remember that they generally work best as a surface mulch around established plants rather than being mixed in large quantities into the root zone of annual vegetables.
37:09
SPEAKER_00: A garden dominated by one crop has a different biological environment from a garden containing multiple plant species.
37:17
SPEAKER_00: Different plants provide different root structures, root exudates, residues, and habitats.
37:24
SPEAKER_00: That diversity can sport a broader range of soil organisms.
37:29
SPEAKER_00: You might rotate crops, plant a cover crop after harvesting an early vegetable, grow herbs and flowers among food crops where compatible, include suitable perennial plants, or allow selected beneficial plants to grow in areas where they won't become invasive or compete excessively with crops.
37:50
SPEAKER_00: Biodiversity isn't simply about making a garden look varied, it's about providing a wider range of resources and habitats.
38:03
SPEAKER_00: Living roots supply carbon compounds to the organisms around them.
38:08
SPEAKER_00: This zone of concentrated biological activity around roots is called the rhizosphere.
38:13
SPEAKER_00: It is an important place for interactions between plants, microorganisms, and nutrients.
38:19
SPEAKER_00: When a garden bed sits empty for long periods, the living roots' resources disappears.
38:25
SPEAKER_00: Depending on your climate and garden goals, cover crops can help keep roots growing between main crops.
38:32
SPEAKER_00: Options may include suitable grasses, legumes, or other plants adapted to your region and planting window.
38:40
SPEAKER_00: But choose carefully.
38:42
SPEAKER_00: Some cover crops require timely termination to prevent them from competing with the next crop or producing unwanted seed.
38:51
SPEAKER_00: For a small garden, even a modest cover crop or a well-managed perennial planting can help keep living roots in the system.
38:58
SPEAKER_00: These four principles work best together.
39:01
SPEAKER_00: They're not four separate tricks.
39:04
SPEAKER_00: There's there are a way there are ways of protecting the habitat, feeding the soil community, and maintaining the physical conditions that allow soil to function.
39:22
SPEAKER_00: Let's bring the science into the garden.
39:25
SPEAKER_00: Suppose you want to improve your soil this year.
39:29
SPEAKER_00: Where should you begin?
39:31
SPEAKER_00: First, observe what you already have.
39:34
SPEAKER_00: Does water soak in or does it run off?
39:38
SPEAKER_00: Does the soil remain waterlogged after rain?
39:41
SPEAKER_00: Does it dry almost immediately?
39:44
SPEAKER_00: Can roots penetrate it?
39:46
SPEAKER_00: Is it compacted where people walk?
39:48
SPEAKER_00: Do you see signs of erosion?
39:51
SPEAKER_00: What plants grow well there already?
39:54
SPEAKER_00: These observations can tell you a great deal.
39:58
SPEAKER_00: Next, consider a soil test.
40:01
SPEAKER_00: A soil test can help identify pH and nutrient conditions.
40:06
SPEAKER_00: They aren't always obvious from looking at the soil.
40:09
SPEAKER_00: This is especially useful when starting a new garden, troubleshooting poor soil, troubleshooting poor growth, or deciding whether to add amendments.
40:23
SPEAKER_00: Avoid adding lime, sulfur, phosphorus, or other amendments simply because someone online recommends them.
40:30
SPEAKER_00: The right treatment depends on the soil, the crop, and the problem you're trying to solve.
40:36
SPEAKER_00: Then look at organic matter.
40:38
SPEAKER_00: Do you have finished compost?
40:40
SPEAKER_00: Can you collect clean fallen leaves?
40:43
SPEAKER_00: Can it return suitable plant residues to the soil?
40:46
SPEAKER_00: Can you mulch exposed areas?
40:49
SPEAKER_00: You don't need to add every possible material.
40:52
SPEAKER_00: Start with safe, appropriate resources and use them in ways that fit your garden.
40:57
SPEAKER_00: If you have a vegetable garden, consider rotating crop families where space allows.
41:03
SPEAKER_00: If you have a long growing season, you might even consider growing a cover crop between vegetable plantings.
41:10
SPEAKER_00: If you have containers, choose a suitable growing medium and remember that container systems behave differently from in-ground soil.
41:19
SPEAKER_00: Container mixes can break down, lose structure, and accumulate salts over time.
41:24
SPEAKER_00: They may need refreshing or replacement depending on the plants and materials involved.
41:30
SPEAKER_00: And if you have a balcony garden and you can st you can still apply the underlying principles.
41:36
SPEAKER_00: Avoid letting containers become chronically waterlogged, keep growing conditions appropriate for the plants.
41:43
SPEAKER_00: Use suitable potting media.
41:45
SPEAKER_00: Return plant material to a compost system where available and appropriate.
41:50
SPEAKER_00: And remember that a container's root environment is still a living environment, even though it is a much smaller and more controlled than a garden bed.
41:59
SPEAKER_00: You don't need acreage to care about soil health, you just need to recognize that the conditions around plants' roots matter.
42:07
SPEAKER_00: Because we are talking about soil.
42:10
SPEAKER_00: Let's keep let's clear up a few common misunderstandings.
42:15
SPEAKER_00: Myth number one: dark soil is always healthy soil.
42:20
SPEAKER_00: Dark color can indicate organic matter, but color alone doesn't tell you everything.
42:26
SPEAKER_00: Some naturally fertile soils are dark, others are lighter in color but still support healthy vegetation.
42:34
SPEAKER_00: Drainage, structure, nutrient levels, pH, biological activity, and local soil conditions all matter.
42:42
SPEAKER_00: Don't judge soil health by color alone.
42:46
SPEAKER_00: Myth two, more compost is always better.
42:49
SPEAKER_00: Compost can be valuable, but excessive or unsuitable applications can create nutrient imbalances or other problems.
42:58
SPEAKER_00: Use appropriate amounts, consider the needs of your crops, and test the soil when needed.
43:05
SPEAKER_00: Myth three, every insect in the soil is beneficial.
43:10
SPEAKER_00: Some soil organisms are helpful, others are neutral in a particular context.
43:17
SPEAKER_00: Some are pests or pathogens.
43:21
SPEAKER_00: The goal is a functioning soil ecosystem, not the elimination of all competition or the assumption that every organism helps plants.
43:32
SPEAKER_00: Myth four.
43:33
SPEAKER_00: You must buy beneficial microbes.
43:36
SPEAKER_00: Commercial biological products can have specific uses, but they aren't a substitute for suitable growing conditions.
43:45
SPEAKER_00: Start by improving soil structure, providing appropriate organic matter, reducing unnecessary disturbances, and choosing plants suited to your environment.
43:55
SPEAKER_00: Myth five tilling is always bad or always necessary.
44:00
SPEAKER_00: Neither extreme is useful.
44:03
SPEAKER_00: Tillage can help prepare certain soils and planting areas, but repeated or poorly timed disturbances can damage structure and habitat.
44:15
SPEAKER_00: The best approach depends on the site, the crop, and the management goal.
44:20
SPEAKER_00: For many home gardens, reducing unnecessary digging and avoiding work when the soil is wet are sensible starting points.
44:30
SPEAKER_00: Myth 6.
44:31
SPEAKER_00: Healthy soil means you never need fertilizer.
44:36
SPEAKER_00: Plants remove nutrients when we harvest crops, and some soils naturally lack particular nutrients.
44:43
SPEAKER_00: Healthy soil management doesn't eliminate the need to replace nutrients when they're depleted.
44:49
SPEAKER_00: It helps us understand how to supply them responsibly and maintain the system that supports plant growth.
44:56
SPEAKER_00: The aim is balance.
44:58
SPEAKER_00: We want to feed the plants while protecting the soil's capacity to function.
45:04
SPEAKER_00: So let's finish our practical section with a simple experiment.
45:09
SPEAKER_00: You don't need a laboratory, you don't need special equipment, you just need a little curiosity.
45:16
SPEAKER_00: Choose two areas of soil in your garden, or two comparable containers if that's what you have.
45:23
SPEAKER_00: If you're comparing garden areas, choose places with similar conditions as much as possible.
45:29
SPEAKER_00: Observe the soil after a dry, a period of dry weather and again after rain.
45:35
SPEAKER_00: Look at how quickly water enters the surface.
45:39
SPEAKER_00: Notice whether the soil forms stable crumbs or clumps, whether it becomes hard and crusted, and whether roots appear to have room to grow.
45:48
SPEAKER_00: If you have a garden bed with organic mulch and another with bare soil, compare how the surfaces feel after a sunny weather.
45:57
SPEAKER_00: Don't treat this as a formal scientific test.
46:01
SPEAKER_00: The conditions may differ in more ways than one, and your observations won't establish a cause by themselves.
46:08
SPEAKER_00: But the exercise can help you become more attentive.
46:11
SPEAKER_00: You might also try the simple squeeze test.
46:14
SPEAKER_00: Take a small handful of moist soil and gently squeeze it.
46:17
SPEAKER_00: Does it crumble immediately?
46:19
SPEAKER_00: Does it hold together loosely?
46:21
SPEAKER_00: Does it form a sticky ribbon when pressed between your fingers?
46:26
SPEAKER_00: These observations can offer clues about texture and moisture, although they don't replace a proper soil analysis.
46:33
SPEAKER_00: You could also dig a small hole and examine the roots of a healthy plant.
46:38
SPEAKER_00: Are the roots spreading through the soil?
46:40
SPEAKER_00: Do they seem concentrated near the surface?
46:43
SPEAKER_00: Is there a dense layer that appears to restrict them?
46:47
SPEAKER_00: Be careful around established root, roots, buried utilities, and irrigation lines and avoid digging when the soil is wet.
46:55
SPEAKER_00: Then write down what you observe.
46:58
SPEAKER_00: Over time you'll develop a much clearer understanding of your garden's particular conditions.
47:04
SPEAKER_00: The point isn't to become a soil scientist overnight.
47:07
SPEAKER_00: It's to become a better observer.
47:10
SPEAKER_00: Because the more closely we observe our gardens, the better our decisions become.
47:17
SPEAKER_00: So let's return to where we began: that quiet garden at the end of the day, the fading light, the leaves moving in the evening breeze, the soil beneath our feet.
47:28
SPEAKER_00: We often measure our garden by what we can see.
47:31
SPEAKER_00: The size of the tomato plants, the number of cucumbers, the flowers in bloom, the basket of produce we carry inside.
47:40
SPEAKER_00: And those things matter.
47:42
SPEAKER_00: But much of what makes a garden successful is happening where we cannot see it.
47:47
SPEAKER_00: The roots are growing.
47:49
SPEAKER_00: Microorganisms are transforming organic materials.
47:53
SPEAKER_00: Fungi are interacting with plants.
47:55
SPEAKER_00: Earthworms and other organisms are moving through the soil.
47:59
SPEAKER_00: Water is entering, draining, and being held in poor spaces.
48:04
SPEAKER_00: Nutrients are moving through biological and chemical cycles, and the soil is responding to every choice we make.
48:12
SPEAKER_00: When we repeatedly disturb it, we change its structure and habitat.
48:16
SPEAKER_00: When we leave it exposed, we make it more vulnerable to erosion and drying.
48:21
SPEAKER_00: When we keep it covered, grow diverse plants, and maintain living roots, we can support the process that helps it function.
48:30
SPEAKER_00: When we retain suitable organic matter, we provide resources that can feed the soil community.
48:35
SPEAKER_00: And when we pay attention to compaction, drainage, and nutrient balance, we create better conditions for the plants we hope to grow.
48:43
SPEAKER_00: None of this, of course, happens overnight.
48:46
SPEAKER_00: Soil building is a long process.
48:48
SPEAKER_00: It is influenced by climate, geology, plant communities, and the history of the land.
48:55
SPEAKER_00: Some problems can be improved relatively quickly, others take years.
49:00
SPEAKER_00: And some soil will always have limitations that we need to work with rather than attempting to eliminate.
49:06
SPEAKER_00: But that doesn't mean our choices don't matter.
49:10
SPEAKER_00: Every season gives us opportunities to learn.
49:13
SPEAKER_00: We can protect the soil beneath our feet, we can avoid unnecessary disturbance, we can keep living roots in the ground when practical.
49:21
SPEAKER_00: We can return suitable organic matter.
49:24
SPEAKER_00: We can choose plants that fit our conditions, and we can stop thinking of soil as an empty container waiting for us to fill it with fertilizer.
49:34
SPEAKER_00: Because soil is already doing work.
49:37
SPEAKER_00: Our job is to understand that work, support it where we can, and avoid disrupting it without a good reason.
49:44
SPEAKER_00: And that brings us back to the name of today's episode, the living earth.
49:49
SPEAKER_00: Not because every handful of soil is identical, or because nature always works in perfect harmony, but because soil is a dynamic living environment.
49:59
SPEAKER_00: It supports relationships we are only beginning to understand.
50:04
SPEAKER_00: It sustains the plants that feed us, it influences the water moving through our landscapes, and it connects our gardens to the larger ecosystems around them.
50:14
SPEAKER_00: So the next time you pull a weed, plant a seed, turn a compost pile or brush soil from your hands, take a moment to think about what lies beneath the surface.
50:24
SPEAKER_00: You may see dirt, but now you know there is so much more happening there.
50:30
SPEAKER_00: Thank you for joining me today on another episode of Old Ways New Days.
50:35
SPEAKER_00: And as we continue into season two, we're going to keep looking beyond the obvious and exploring the systems that make self-sufficiency possible.
50:43
SPEAKER_00: Because growing food isn't just about what happens above the ground.
50:46
SPEAKER_00: It's about understanding the living world that makes the harvest possible.
50:50
SPEAKER_00: Until next time, keep growing, keep learning, keep tending the earth, and keep finding ways to live a little closer to the land.
50:58
SPEAKER_00: May your soil stay covered, your roots grow deep, and your garden keep teaching you something new.
51:04
SPEAKER_00: We'll see you next time.