Soil Food Web Basics

Soil Is Alive

A single teaspoon of healthy soil contains more microorganisms than there are people on Earth. These organisms (bacteria, fungi, protozoa, nematodes, and arthropods) form an interconnected food web that drives nutrient cycling, disease suppression, and plant health.

When you feed the soil food web, the soil feeds your plants. This is the foundation of regenerative growing.

The Key Players

Bacteria

The most numerous soil organisms. Bacteria decompose simple organic compounds, cycle nutrients, and form beneficial relationships with plant roots. Some species fix atmospheric nitrogen.

Fungi

Mycorrhizal fungi extend plant root networks by orders of magnitude, trading minerals for plant sugars. Saprophytic fungi break down woody material that bacteria can't handle. A healthy fungal network is especially important for perennial systems like food forests.

Protozoa and Nematodes

These microscopic predators eat bacteria and fungi, releasing nutrients in plant-available forms. They're the nutrient-cycling workhorses of the soil food web.

Earthworms and Arthropods

The visible engineers. Earthworms create channels for air and water. Beetles, mites, and springtails shred organic matter into smaller pieces that microbes can process.

Bacterial vs. Fungal Soils

Different plant communities prefer different soil biology:

• Annual vegetables thrive in bacterially-dominated soils
• Perennial plants and trees prefer fungally-dominated soils
• Grasslands fall somewhere in between

This is why a food forest bed needs different soil management than a tomato patch. Woody mulches encourage fungi. Green manures and compost encourage bacteria.

How to Support Soil Life

Stop Tilling

Tilling destroys fungal networks, compacts soil structure over time, and exposes soil biology to UV damage. Use no-dig methods: sheet mulching, compost top-dressing, and cover cropping.

Keep Soil Covered

Bare soil is stressed soil. Mulch, ground cover plants, or cover crops protect soil biology from temperature extremes and UV radiation.

Add Diverse Organic Matter

Compost, leaf mold, wood chips, and chop-and-drop mulch all feed different parts of the food web. Diversity in inputs creates diversity in biology.

Minimize Chemical Inputs

Synthetic fertilizers, herbicides, and fungicides all disrupt soil biology. Healthy soil food webs make many of these inputs unnecessary.

Measuring Soil Health

Track your soil's progress over time with regular testing. Key indicators:

• Organic matter percentage: healthy soils are 3-6% organic matter
• pH: most food crops prefer 6.0-7.0
• Aggregate stability: healthy soil forms crumbs that hold together when wet
• Earthworm count: 10+ per shovelful indicates good biology

Use the Soil Tracking section in PatternBase to record test results and watch trends over multiple seasons.