Portable Trees

written by

Joel Salatin

posted on

July 1, 2025

Today's Polyface patrons, unfortunately, do not have the privilege of meeting my dad, who was a genius and visionary. His one negative trait was becoming weary of routine; he loved the new thing, the innovation. Much of his early innovation after we came to Swoope in 1961 was about stopping biological leaks or wastage.

How do you leverage the juvenile growth spurt in grass? How do you feed earthworms and build soil with on-site material? And one of the biggest ones: how do you capture manure and urine generated by grazing animals?

As we began moving cows from paddock to paddock with his portable electric fencing system, he saw a desperate need to make portable shade for the herd's comfort and especially to spread pasture droppings around. On hot summer days, animals, like people, look for shade. Historically, this means trees.

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But trees are not everywhere and trees don't disperse the fertility. They instead offer campsites for cows, concentrating the droppings instead of spreading them, and turn into incubators for parasites and pathogenic organisms. Besides, the deep-rooted trees don't need the manure; the pasture needs the benefit of animal droppings.

Thus began a project to create a shademobile that could act like a portable tree. As early as 1820 John Taylor of Caroline, a friend and neighbor of Thomas Jefferson, in his book Arator mentions the need for an "ambulatory shade structure" for cows to strategically place their droppings in the field. But no one had done it until Dad built one.

He found a burned-out 50-foot mobile home, towed it to the farm, and began retrofitting it into a 20 foot wide by 50 foot long tricycle shademobile. Big enough for about 100 head of cattle, it literally drove our fertility engine. In those days, with poor soils and lots of brambles and woody weeds, the results were dramatic. We could park that thing on some Devil's Shoe String and the next year that rectangle was solid white clover. No seed; just heavy impaction and manure.

The green rectangles had a 5-year effect and began transforming our worn-out pastures into lush vegetation. For many years that shademobile sheltered the cows and enabled us to strategically place their droppings where they were needed most. The shade also reduced ammonia vaporization from urine and manure.

Over the years, however, that rigid 50x20 design became problematic because it was too big to go down tree-lined farm lanes and certainly impossible to take down a public road. When Polyface began renting nearby properties in the early 1990s, as part of our ongoing expansion, we needed something that could be transported down a public road. An outfit began building a circular shademobile that could collapse but it was extremely expensive--$23,000.

We began experimenting with smaller models on retrofitted and extended hay wagon chassis. We've built several and could hook them together to accommodate a larger herd. But hay wagons are hard to tow down the road, and the knock-down to 8 ft. and subsequent re-furling of the shade cloth canopy takes a couple of people and some time. They work, but not efficiently enough to say "we've arrived."

Around the dinner table, then, we brainstormed many ideas. One was a light conduit grid held aloft by helium weather balloons. In typical brainstorm-running humor, we imagined attaching it to a cow. Wherever she walked, that's where the shade would be.

Currently, we are working with a fellow in Missouri who has designed a glorified umbrella. It works just like an umbrella with a center pedestal and crank-up tension. He's built several, and we have Gen1, Gen2, and Gen3; a total of 3 prototypes we are using in the field to test functionality and durability.

We don't know if this is the optimal design. We've discussed rigid inflatables and horizontally collapsible trusses. It's all on the table, but we believe in the next couple of years we'll arrive at an affordable, efficient, durable model to take dad's original concept to the next level.

The bottom line is this: at Polyface, we never stop refining and innovating in order to do what is right and better. Our commitment is to come alongside biological processes and enhance them. Conventional industrial agriculture cares not a whit about natural biological processes. It views all life as a mechanical issue.

We view life as fundamentally biological. Our mechanics are not supposed to override biology with disrespect; they are meant to caress ecological needs with our ingenuity. This brings inherent abundance and immunological vibrancy.

Be assured, your continued interest and patronage enable our ongoing innovations into the future. 

Thank you.

Joel Salatin

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Food Shortages

I'm in Oregon today speaking at the Azure Harvest Festival and a question from the audience during a Q&A stimulated a lot of discussion:  "What do you think about the possibility and preparation surrounding food shortages?" David Stelzer, founder of Azure Standard, answered that the issue is not food volume, it's food nutrition.   That was an interesting answer that has a lot of merit.  As a nation, we are overfed and undernourished.  This is the crux of the MAHA movement and the epidemic diseases we see in our country. At Polyface, we know the pastured meat and poultry we produce is far superior in essential phytochemicals and other nutrients due to the carotenes, exercise, and stress-free habitat we offer.  You can taste the difference, feel the difference in texture, and measure it empirically. Perhaps my most poignant affirmation was our cat test.   We purchased meat from the supermarket and offered our own for the four cats.  They wouldn't touch the conventional meat (ground beef). Even though two plates and four cats would be much easier to accommodate if they spread out, all four crowded around the plate with our meat, eating it all and licking it up, before later sniffing and gingerly eating the supermarket counterpart. Since cats don't understand TV ads or USDA propaganda, they know what's good and what's not.   We encourage anyone dismissive of food differences to ask their pets:  you can trust them far more than doctors and experts. Yes, I get the nutrient deficiency angle on the shortage question.  But I'd like to explore it a bit further.   Right now, the world throws away more human-edible food, as a percentage of production, than at any time in human history.  The planet is awash in food.   Some 40 percent gets thrown away because it has a slight blemish, exceeds the sell-by date, or is tainted in some way.  We have a fundamentally segregated food supply rather than an integrated one, and that creates a lot of unusable waste. The vulnerabilities of our food system, I think, are much more subtle.  When I was in Uruguay two years ago, speaking at a conference, one of the other presenters was from Germany and showed a soil map of the globe.  Not a single commercial agricultural region had a stable or positive soil trajectory.  Every single area on the planet is losing soil; some faster than others, but globally our soil depletion continues without any sign of abatement. This is not a good trajectory.   As much as the technocrats promise food without soil, that's not the way to bet.  Soil is the skin of the earth.  When it goes, famine results.   The main difference now compared to centuries ago is that we have the capacity to move food around.   Nobody starves due to a lack of food on the planet; they starve due to socio-political unrest and dysfunction. But what happens when massive areas can't grow anything anymore?  Even being able to move food around doesn't help when there isn't enough.   The soil trajectory does not look good.  But at Polyface, we're building soil.  Areas covered with shale (layered rocks) half a century ago now have a foot of soil on them.  That's not the 3-5 feet that 150 years of inappropriate tillage eroded, but it's a build-back start. In addition to soil loss, as a planet we're seeing hydrologic decreases.   The Oglala aquifer, which undergirds the irrigated agriculture in five states, has dropped more than 100 feet in the last half-century.  At its current rate, it will be unpumpable in about 50 more years.  Imagine if all those circular irrigation pivots in Nebraska and Kansas shut down.  What then? At Polyface, we keep building ponds to inventory surface runoff.  By definition, surface runoff occurs when rains come too fast at once or too much at one time for the soil to absorb it.  Holding that and using it strategically in a drought is a way to reduce flooding during rain events and grow grass when it gets dry.  This is one of the most landscape resilient techniques we can implement. 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But at Polyface, we keep these vulnerabilities at bay with compost fertilization, pasture rotations, and lots of species diversity, including pollinators and wildlife. Here's the point:  the basic long-term vulnerabilities in the planet's food systems could all be reversed with practices Polyface uses every day.  Looked at another way, the entire food shortage question could be answered if eaters and farmers implemented these ecological and immunological protocols, working together to rather than completely separated.  We don't need to fall into an abyss of starvation. If we all simply began eating food from farms that build soil, increase water, and stimulate immunity, we could deliver a hospitable, abundant planet to our children.   Reversing these trajectories wouldn't take much time or money.  It takes intentionally-minded folks who connect the chain of sustenance from their plate to the planet. Polyface patrons do that.  Thank you.  Let's heal the land together. Joel