Building beds with bricks

The mulch-generating polyculture for Mortal Tree’s PASSIVE garden system is going well. It’s the bed in Foundation for a future I am establishing with bricks.*

The intent for this bed, per A bit blunt method, was to shift the rocks every couple of months to kill off the grass underneath. This worked pretty well for most of the bed. I shifted the bricks in July and made a final small shift about a week ago. Above is the freshly shifted “mulch” around an amorpha.

I also tried covering a small part with grass mulch in May last year, and this took care of any weeds growing through the cracks. Below is the planting now. Like most fun times, there is a mess to clean up afterwards. This bed had a lot of fun last year. What you see is actually mulch I applied, the healthy comfrey, and some amorpha interplanted. I plucked out the little bits of green quackgrass, and look forward to some very lush, beautiful growth here come summer.

I plucked out the quackgrass when I shifted the rocks. Because they block sun and moisture loss, the rocks encourage the quackgrass to grow shallow, allowing me to just pick them up rather than pulling them. What roots did grow deeply are easily pulled because the soil is so soft under the bricks.

 


This soil conditioning is one if the main perks of using rocks. The soil life is everywhere, with centipedes, worms, spiders -even at this cold season. Soil between the bricks which heaved from the freezing over winter is unbelievably friable. It looks like it has been tilled.

Considering how low this soil is in organic matter, with a clay-coal base, with no amendments like sand or ever even being tilled before, I am very excited to already have such results. The moisture and soil life have brought it so far because I have created the right habitat, covering the soil. The organic matter is starting to accumulate.

Above are some amorpha leaves dropped last fall, which likely have brought in nitrogen the system formerly did not have. The plants were already beginning to nodulate in their pots when I planted them last year. If you would like to learn more about how I ensure they make nitrogen and get off to a good start, I have some notes here on Growing amorpha.

I also harvested some of the comfrey leaves last year, which I left around the plants I harvested from. This is breaking down into gorgeous soil, bringing in carbon the system did not formerly have.

Pictured is some broken down comfrey from a larger patch in the food forest. This new patch should be producing similar soil in the near future. It’s already well on its way.

 

*This could have been done with some large piece of canvas or the like, or a large piece of plywood. One of my clients decided to try clear plastic just to block water, which was still effective at removing the plants underneath.

Up the chain: trophic system moderators

“What limits size and growth?……..

We ourselves are part of a guild of species that lie within and without our bodies….. Most of nature is composed of groups of species working interdependantly, and this complexity too must have its synchronistic regulators.”

-Bill Mollison Permaculture: A Designers Manual

Rummaged potting soil and dried, dead little seedling roots dangling in the air was a recurring sight in our greenhouse a couple years ago. Whole flats of peppers would have their tops nipped off and the like because of mice.

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Our heated greenhouse.

Poisons, traps, and even some nasty sticky pads lined the floors waiting to dole out death to the offenders, but they were ineffective. The traps caught few mice. The destruction continued. The sticky pads outside our sprouting room caught sparrows which I had a hard time cleaning the nasty goo off trying to save. Nothing worked until we got a cat.

Esmerelda is a small, long haired drop-off cat, but is the best mouser I have ever seen. For a while after she showed up, I would regularly pass her walking up the driveway with a fat vole in her mouth. As I raked out last season’s growth in the greenhouse, her face would be stuffed right in the middle off my work, waiting for a vole to dash from its dinner table.

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Esmerelda and Niki

Now when we plant, the only thing mice bother is fresh squash seeds, but even those are seldom touched. Having made some hanging shelves to keep the squash seeds out of reach, it’s difficult to tell if we have mice or voles at all.

Making friends with rodents is recognizing what voles, mice, and many of the technically-not-rodents like rabbits and ground hogs do for our plants I explained in the earlier post. It also means keeping their numbers in proportion to the rest of the ecology. Artificial trophic system moderators, such as traps and poison, aren’t that effective. What is effective, is encouraging these rodents’ predators.

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Perched Niki

As a USDA Certified Organic farm, we actually have to submit a written explanation of how we manage trophic levels such as rodent population, and Esmerelda is officially accepted as part of that system.

Owls are major predators of mice and other smaller rodents. Barn owls, which have species across the globe, eat at least one rodent a night. A pair with young captures as much as 3000 per year according to some sources, which would certainly keep about any rodent population in check.

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One of the many subtly varied species of barn owls. Photo by Jim Vallee

Barn owls are fairly ubiquitous, so the chances of hosting a pair is pretty likely if you have old buildings, hollow trees, or nest boxes where they can raise their young.

In addition to preying on mice, larger species of owls can prey on rabbits. We have a pair of great horned owl on our farm, which we likely wouldn’t have known about if it weren’t for the faint sunlight betraying one of their silhouettes as it ghosted off one evening. We had some young pullets at the time the owl’s were picking off once a day at dusk. The remedy was caging up the pullets earlier in the evening and letting the owls go eat the mice and rabbits.

With this kind of appetite and stealth, great horned owls can obviously carry away some rabbits. Studies have shown even these big owls though also like mice, and that a pair will catch up to a dozen a night when feeding young.

Dogs have a pretty broad array of prey. Foxes prey on mice and rabbits. Larger animals like coyotes can prey on groundhogs, but few of us want those close to our gardens and homes. This is why we domesticated them.

We have a rat terrier, named Daisy -named after the bee bee gun brand. We got her specifically for managing the rodent population, which she does very well. Despite her small size, she also gets possum and groundhogs. This is because we’ve carefully trained her.

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Daisy hoping to get a bite of that pea. She loves veggies.

We have adhered to the idea that dogs seldom hunt alone, almost always in packs, with one taking the attention, others lunging in for the kill. Daisy has always been taught that if she finds something, we will always come to her aid. If she finds a mouse under something, she barks, we come, and do what we can to move things around and let her get at it.

This is especially important when she beats a very large groundhog to its hole and lays into them. She kills her prey by lifting it off the ground and giving it a whip, snapping it’s neck. As a result groundhogs larger than her are pretty much impossible for her to kill alone. She has always been taught that someone will show up shortly to make the final blow while she keeps it’s attention. She can handle young groundhogs herself.

Our neighbor had a much larger dog they would keep in their fenced garden area at night when the sweet corn was about ripe. This kept raccoons from pillaging the place.

Some might object that allowing an animal to kill anything makes them a threat to their human caretakers. I think this is more a matter of teaching the dog who is a friend, who is a foe, who is above them, and who is below them. This sounds petty among us humans who obviously function differently, but this is how dogs work. Even with animals that could and should be prey for Daisy, we have trained her to not kill.

If our rabbits get out for instance, we sic her on them. She catches them by simply holding them until we come pick them up. She doesn’t pick them up and snap their neck as is her method to kill anything else. The rabbit is a bit slobbered-on after this, but in my experience, catching rabbits alone is seldom less stressful for the rabbit, usually unsuccessful, and simply leaves the rabbit prone to being eaten by a raccoon -because they certainly don’t care about a rabbits quality of life.

In general, I think cats and dogs enjoy a much better quality of life when they are allowed to express their instincts. If we can figure out a way they can do this without endangering us, this is a mutually beneficial relationship.

Across the board, effective ecology creation means making friends with your pests. Sometimes, keeping a balance means making friends with their predators.

Featured on Plant Scientist

I’ve been working with Sarah Shailes, the curator, and writer of the prestigious Plant Scientist blog, to feature The rules of spacing, which was such a hit here a couple weeks ago, on her site. She published it today. Thanks to Carolee, a follower of Mortal Tree, for already liking the guest posting. Find the post here: The rules of spacing


While you’re there, you might like to check out some of the other articles Sarah and her guest writers have compiled. I have followed Plant Scientist for years now, and always appreciate the detail of the subjects explored there.

Making sense of wild seeds

I’m not quite sure what it takes to sprout Turkish rocket (Bunias orientalis). Last year I posted a fairly certain observation that a couple weeks in cold temperatures does the trick, only to find in the comments from the ever apt Wooddogs3 that she had sprouted quite a few straight out of the packet in warm weather.

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Scratch that idea. I figured something else must have deterred my Turkish rocket sprouts; but then, in later conversation, Heather mentioned that more Turkish rocket sprouted after the pot sat out over winter. (?)

I think the fact of the matter is we are working with fairly wild, unselected seeds. With them, variance is the standard. At the same time, it offers several little known benefits.

Varying the time of germination increases the likelihood at least some of the seeds will sprout in a ‘sweet spot’ of a season, or at least avoid catastrophes, and make it to adulthood. What if an unusually late frost hits or some animal nips off the tender sprouts?

This is a very helpful character for love-in-a-puff vine (Cardiospermum halicacabum) which I’ve grown on a large scale for the last couple years. It’s a warm climate plant, and can’t take frost. I nevertheless plant it in mid April, when we still have a chance of frost. While a few will come up as early as three days after planting and get nipped, the majority of the plants take about two weeks to sprout, and will continuing sprouting up to three months after.

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Cardiospermum sprout back when I tried growing them in flats. Because their sprouting time was so varied,  I watered the flats a lot longer than expected for all the seeds to sprout. They don’t transplant very well anyway, so I now direct seed.

The mechanics that govern this variance can vary, but are usually based on the activity of certain enzymes releasing nutrients necessary to wake up and nourish the embryo that will become the new plant.

Health conscious readers may be familiar with the discussion of improved nutrition in sprouted or soaked grains because the phytates present in these seeds have been removed (see here for more info). This is because in the seed, phytates bind up nutrients -phosporus in particular- keeping them off limits for the embryo (1). Water is one factor that initiates the enzyme phytase, which is responsible for breaking up the phytates (2). In the right temperature range, phytase completes the breakdown of the phytates, releasing the nutrients the embryo needs for growth. In most cases, the need for adequate water and longer durations of certain temperatures ensures the plant can grow to maturity once it sprouts.

Of course, many of our perennial vegetables also need cold, moist temperatures, or dry and warm temperatures, in addition to a later stage of warm moisture to successfully sprout. Phytates are one example of the mechanics generally at work in seeds -enzymes releasing nutrient.* Differences in the genetic makeup can dictate the time each seed takes to activate these enzymes, and release the nutrients for sprouting. Its variance in genetics that often gives such extreme variance in sprouting time, and what conditions are necessary to induce germination.

Most of our garden vegetables were the same way at one time, with lots of variance. They’ve just been selected. If over the next ten years I only saved seed from cardiospermum that sprouted two weeks after planting, this character would soon be the norm.

Although it’s nice to have an idea what’s going on in those drab looking little seeds as they deny us a happy sprout, what can we do to improve the likelihood that we, at some point, actually get a sprout?

Heather had the right idea leaving her Turkish rocket in the pot to see if any more sprouts would show up. Just give the seeds time, and changes in temperature.

I know from experience that keeping a little empty pot of dirt safe for seasons at a time is not easy. As a first step, designate a spot where seeds are protected -by mandate of heaven -or whatever works for you. Tell this to anyone that might come along thinking your untidy plant-keeping needs tossed in the trash.

Rodents seldom care about the mandate of heaven, so cover the seeds with some mesh, or build a hanging tray well above the ground, as Martin Crawford does, to keep them out. I hung some trays in our greenhouse last year which did the trick keeping mice out of squash seeds. The only problem with hanging trays I find is their fluctuating temperature: pots placed on them can easily dry out on a hot day.

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Seeds are more likely to stay moist and live if they’re in more temperate climates surrounded by bricks in a shady corner. My favorite spot for sprouting is on the east side of our garage, or on the north side of our greenhouse. I’ll bring the trays from these temperate spots once in a while to the hot greenhouse. For a short time here, I watch them, and keep them watered, while transplanting any sprouts that appear. Once the sprouts stop appearing, I move them back to the less intense climate.

This system is very effective at getting around the errant nature of our prized perennial vegetables and trees. With such complexity, it’s better to just offer a variety of situations to seeds, and wait, rather than trying to guess what’s going on in those drab little seed’s dreams.

*There are even several kinds of phytase. See here for more info.

Orchard understory

Is the space around your trees still empty? Try these plants:

10 Companion Plants for Orchards (~4min read)

This article provides a pretty neat survey of plants that, together, make a diverse, healthy, productive orchard. Any of the listed plants of especial interest?

The rules of spacing

I was at a Christmas party in conversation with a local Timken engineer who, hearing I design food forests, wanted to pick my brain on apple trees. He had six trees in two rows of three, well spaced in his backyard. He was throwing out terms about the mainstream organic sprays he was using, and framed his questions expecting me to know some super organic spray, or spray regimen, that would fix his problems of pests and low vigor in general. I don’t think he expected the answer I gave: ‘What’s planted around the trees?’

We often think of the rules of spacing as rules for keeping other plants away from each other. In practice I find the lines blur between species, and enters a much more broad science: it’s what should be included near the plant, as well as what shouldn’t. Between these two aspects, you make or break the majority of fruit tree problems.

The lines often blur between species because, let’s face it, plants don’t grow in a vacuum and always have something growing up against them. In this guy’s case, his trees were planted right into his lawn. They were in competition with the grass.

Looking at their history, grass and trees are in most cases nemesis of one another. Trees make forest; but grass needs open space. The setting in most yards of trees with grass between is quite artificial, and only exists because we keep the grass mowed. In any other situation, trees would take over.

The prairies are the kingdom of grass, and these occured because of rain shadows, or areas where circumstances such as the Rocky Mountain range messed with the winds that carry rain, creating droughts in one part of the year, and near flooding in another. Trees don’t like that, because most have relatively shallow roots, as much as 80 percent residing in the top three feet of soil depending on the kind and its conditions; but prairie plants, such as the grasses, and N fixers like senna hebecarpa, put roots down unusually deep, so reach the water table whether rain comes or not.

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An experiment showing the root growth of Red Delicious apple tree two years after planting.
Have you ever wondered as you pass woods how the trees survive so close? If you were planting an oak tree in your yard that would someday reach a hundred foot tall, can you imagine the spacing recommendations? They would be over fifty feet apart. Most yards couldn’t fit more than one tree. But in the woods they stand on top of each other, growing for hundreds of years, happy, and healthy.

Studies have shown that trees can grow their roots deep into the ground, but prefer to keep their roots higher in the soil if possible. There is more organic matter, hence nutrients and water, in this layer. If there isn’t, trees will try to put in the work to grow deeper. This is a lot more work, and certainly isn’t their first choice.

What trees really prefer is building networks in which they share and preserve resources. For instance, trees have what is called hydraulic redistibution, which is a fancy term for moving water not only up for their own use, but back down into the soil for storage, and horizontally to other plants. Peter Wholleben, in his book The Hidden Life of Trees recalls his surprise when he found a ring of roots from a beech tree that must have been cut down well over a century beforehand, but still had green, living roots showing above ground. It had no leaves, and the stump was gone. As he explained, citing various studies, the living trees around this ancient (should be dead) tree were feeding it sugars made in their leaves, keeping it alive. Likely, they got some kind of kickback from the extended root system because it allowed them access to more resources.

This is in ancient, established forests, so conditions aren’t quite the same for our young transplants. We can get some similar effects by growing fruit trees in more open settings, or riparian zones. These are zones similar to fencerows and overgrown fields where grasses are just converting to trees. These zones are iconically untidy and wild; but skillful gardeners know the elements of these zones, like clay in a potters hand, have the best potential to form the most beautiful, lush gardens.

Riparian zones have many layers, with notably high numbers of low growing herbaceous and woody shrubs, many of which are nitrogen fixers. The quickest way to simulate this ecology is making ‘guilds’ of plants right around your fruit trees. Here is my manual of bed building for info on quickly clearing grass without tillage. Plan on expanding these plantings every year until the beds around your trees meet. If the tree is older, and larger, the bed should extend at least a couple feet beyond its drip line.

An example guild: 1. Fruit Tree 2. Comfrey 3. Siberian Peashrub 4. Amorpha fruticosa 5. Japanese Wineraspberry 6. Honeyberry 7. Blueberry 8. Turkish Rocket 9. Crambe cordifolia 10. Stepping stones, (or in this case, stepping logs). The green base is a ground cover of mint.
Any guild should include at least 2 woody nitrogen fixing plants, about 5 plants that do not fix nitrogen but can be cut for mulch, such as comfrey, or a groundcover of something like mint, then several fruiting shrubs like raspberry or honeyberry, and some perennial vegetables.

This is the best method if you already have fruit trees in the ground, like our engineer friend. If you’re just planning your food forest, Robert Hart, the father of the northern food forests, recommended planting full size or standard fruit trees at recommended spacing for their size, in rows like any orchard, but then semi standard or medium trees, then dwarf trees, then shrubs, then herbaceous plants, then vines to climb and fill in the cracks between them.

Photo credit: Graham Burnett.
I’d recommend mulching as much as you can, and planting that area with a complete planting like this. The space should be completly filled with plants, and will establish faster with less work overall.

This system gives quite attractive results that are increasingly less cost and labor than serial applications of even organic, clay-based sprays, pyrethrums and neems, let alone the more harsh chemicals. There is work later on, but this is of course dabatable, because its mostly harvests of fruit. Sounds like pleasant work to me.

Moles: a link in the trophic chain

“Mole starts with M, and and M is for meat” as I once read. Moles don’t eat much plant material, they mostly eat worms and grubs -meat. What does it mean if you have a high mole population? You have a lot of worms, grubs and the like -a thriving ecosystem to sustain the little diggers.

Farming with Nature: why we welcome moles on the farm (~2min read)

This article gives a little more explanation on how moles benefit their ecology. 

Moles also eat young, ground-dwelling cicada nymphs. We were plagued by the adult cicadas this year. If I can get a higher mole population, perhaps I’ll have fewer of these bugs when they’re next due to emerge circa 2029. That would be nice.