6 October 2025

Did you know that 59% of life on Earth is in the soil? From mammals to microbes, the soil seems to be the one place where biodiversity is increasing (because scientists are continuing to find new life forms here), with more than half of the species on the planet calling soil home.

I learned this yesterday at the Fungus Festival on Randall’s Island in NYC. For me, the primary draw was Cam’s Urban Farm, but the more I learn about mushrooms, the more I love them!

I caught a great presentation with Hector Prudhomme of the New York Mycological Society: Rooting the Future: Mycorrhizal Fungi, Farming and Climate Change. I’m already a big fan of mushrooms as an edible and nutritious delicacy (I know of no other way to grow healthy food in such a small amount of time and space), but Hector’s talk gave me a greater appreciation for all they do.

Soil is critical to life on Earth. If you’ve been reading my blog for a while, you’ll know that one of my all-time favorite films is The Biggest Little Farm, a story about converting lifeless dirt into a thriving ecosystem. Living soil - packed with mycorrhizal fungi and their associated microorganisms - is a tremendous carbon sink, provider of nutrients to our food, and sponge-like protector against flooding and erosion. At the current rate of soil degradation, however, the world’s topsoil could be gone within 50 years.

Loss of topsoil not only reduces crop yields, it releases captured carbon and diminishes the land’s resilience.

Beyond all this, as a Registered Dietitian, I am truly concerned about the challenges to nutrient density imposed by depleted soil. The Nutrient Density Initiative provides information and resources for consumers, farmers and businesses to advance the win-win cause of regenerative agriculture for food production. Practices which improve the health of the soil pass many of those benefits - nutrient-wise - on to us as consumers. Many farmers have found that working with nature also reduces their costs; imagine that!

Let’s talk about our “modern” agricultural system. Monoculture crops (even if they’re “organic”), intensive tillage, and synthetic fertilizers and pesticides all contribute to loss of topsoil and destruction of the mycorrhizal “wood wide web”.

If we think about our soil as the microbiome of the Earth, we want to treat it as well (or better than) our own gut microbiome. That means healthful inputs (compost and cover cropping) and diversity (varied crops and crop rotation). This, in turn, produces healthier - and more satiating - food.

Winner, winner, veggie dinner!

So what can you do to support the life underfoot - the foundation of our health?

• Pay attention to the Farm Bill! This multi-year, 1.5 trillion dollar bill has been limping along on short extensions since 2023 and technically - with the current government shutdown - has expired. This means farmers can’t plan (and you know what they say about those who fail to plan). The Farm Bill has huge potential for (a) encouraging farmers to transition to regenerative practices and (b) allocating nutrition resources (SNAP and SNAP-Ed) in the direction of sustainable agriculture.
• If you are able, try permaculture in your own backyard (think: composting, keeping soil intact, diversity of plants) and/or support farmers who utilize regenerative and organic practices. Buying produce from a local farmer’s market gives you a chance to talk to the farmer about his/her methods.
• Avoid chemical fertilizers and pesticides, which harm mycorrhizal fungi in two ways: they lead to nutrient imbalances that reduce plants’ reliance on the mycelium and [fungicides and pesticides] directly destroy the diversity and abundance of fungi. If you’re wondering how to keep your lawn green and lovely without these chemical inputs, consider reducing grassy spaces in favor of native habitat.
• Support continued research on fungi. They may just be one of the best partners we have in protecting the nutrient value of our food supply and defending against the worst impacts of climate change. Find more info at SPUN (Society for the Protection of Underground Networks).

We can’t and won’t change everything all at once, but it’s clear the current system leaves mush-room for improvement!