1 1/2 year old forest garden, nice tomatoes on 6-7 foot plants to the top left. |
Here's one method we used to cover very large areas where it didn't need to look neat right away, in this case, a 1/4 acre thicket of old-field with brambles, weed tree saplings, and bushes, honeysuckle, poke, burdock and ragweed.
Yeah, try tilling that, or maybe smothering it under a layer of cardboard!
We needed:
--fast,
--low-labor as we were very busy,
--cheap, no special tools like a tiller.
--garden beds that would EVENTUALLY be water-saving, fertile, and low maintenance.
We had:
--lots of bio-mass, sticks, leaves, weeds, etc.
--time for beds to gain fertility naturally
--other "intensive" garden beds for high productivity, so we were looking for a system that would prioritize "low maintenance" over productivity.
Here's what worked for us:
(Very) Rough Mulch Garden Beds.
OR, chop, drop and pile it up.
This is a technique based on restoration work and studies of building soil by mimicking the "course woody debris" in a forest. Now, I wouldn't recommend this for someplace close to the house where you need things to look neat right away. But in out of the way areas of unused farmland, bramble and old field, I think this could work well for you. Also, if you're starting with a large area of lawn, this WOULD still work, but step one would be: "stop mowing your lawn and wait for a couple of years." Compared to the work of plowing, digging or sheet mulching lawn, working with succession like this might still be quicker and easier for large areas! I might even try gathering a bunch of nuts and seeds from a rest stop or park and stomping them into the lawn as "sacrificial trees."1. Clear vegetation as low as possible. In a bramble or old field, you might be able to do this completely with hand clippers and a small hand saw, as I did. But we did have one maple that had died prior to us buying the house and a catalpa that was dying, probably from years of competition with the maple. So we removed the maple and cut the catalpa to regrow as a smaller tree ("coppicing.") Don't sweat getting weeds and trees cut as low as a conventional sheet mulch. Sure, weed trees and bushes shot through in the spring, but they were more help than hindrance, providing additional mulching materials and mass and tilling soil with their roots. Others, I have left to work their magic on the soil, I can cut them later with hand clippers.The important thing is that you expose plants you want to grow to more light.
2. Layout paths with your largest woody debris. Woody debris helps create a fungal soil that inhibits grass and builds loose soil that weeds and grasses pull out of easily. The large debris helps you visualize where your paths will be. Make garden beds 4-5 feet wide, so you can reach the middle from both sides.
3. If you want them to be water-wise, then lay the sticks PERPENDICULAR to the slope to slow down and infiltrate water. This method, called "PASSIVE SWALING" causes the sediment to fall out of the slowed water and where it slowly forms a swale without digging. Our beds are like giant "U" shapes, designed to catch water coming down hill.
4. (Optional) "Trench Compost" in a few relatively root-free spots where you can dig. Trench composting is just digging a 1-2 foot deep hole, building a compost pile in it and covering it back over. Just don't bury too much woody material or you'll bind up some nitrogen for a few years.
This part is really just voodoo, but it gives me a chance to inspect the soil and I theorize that it "kickstarts" soil life which will carry the nutrients out into the beds, and encourages roots to till the soil by providing nutrient stores for them to grow into.
5. Pile up the rest of your debris on beds using smaller sticks, weeds, leaves, any organic matter you can find. Lay the sticks and twigs in sort of "bundles" parallel to the stick borders as you gather them to create a more solid mass. The thicker, the better. Avoid placing large sticks in the spots you will directly plant, using smaller debris instead in these areas.
7. Plant into beds as you would with any sheet mulch: In spring, you can dig small holes in the mulch for plants, or make a pile of compost or soil in the mulch for a seed bed.
Finished beds, left, right and foreground |
7. Maintain your beds with thick plantings and "chop and drop"mulching each year.
"Chop and drop" is just what it sounds like. Cut your crop and leave it to compost in place on the garden bed. Spot mulch any weedy areas or large grass patches with newspaper and some garden debris.
That's it!
"No newspaper or weed barrier?" Nope. That takes lots of time... and newspaper I didn't have. Yes, there are SOME weeds, but really, according to many sources on forest restoration, 6 inches of debris is going to kill most of your weeds. Check out the surface of a two year old bed:
Not too many weeds in there. Lots of room for plants to grow. And believe me, I didn't weed!
"And hows productivity?" Better than no garden bed, which is what I'd have with any other method. And actually, it was pretty good, though I did no measuring. I got lots of healthy tomato plants, lots of tomatoes, dozens of squash, peppers, basil, etc, just off one of these beds. And the deer probably got more than we did. That's pretty good considering I never dug, never watered, never weeded, and never fertilized.
And I know this bed will continue to grow in fertility for a long time as the wood slowly breaks down.
So there you have it. It might not be for every gardener or every situation, but it might be for that hunk of land you've been waiting for....
Thanks for sharing this, I've done some mulching / soil-covering with woody debris in areas I'm trying to coax back to woodland (an area of lawn that borders an existing treeline with several species of trees and herbaceous plants established), letting the Sassafras colony expand out to give me more of a buffer of privacy in that area as well as a readymade, fast-growing (by root suckers) tree infill.
ReplyDeleteI threw a few old squash/pumpkins in there last year to see if any would grow on their own as a groundcover, but with poor results; this year I'll try deliberately planting a few things into this area and see what happens, the soil should be getting more friable now that it's been a couple of years. I've also used brush on top of cardboard to keep the cardboard from blowing away and/or piled around tender young tree/shrub transplants to keep critters from munching them down; I think they appreciate the microclimate and protection.
I forgot to add that I've also done a lot of scattering all kinds of brush, leaves, woodchips, logs, and whatever other organic matter I can get my hands on, just to cover the soil in areas where it's especially poor and can only support a scant cover of moss, dewberries and knapweed.
ReplyDeleteI attribute a lot of this degradation to the action of moles, who seem to kill most anything growing above as they tunnel prolifically through my sandy soils, exacerbating the dryness by creating these air spaces which stop moisture wicking up from below, and it takes probably a year or two for rain/frost/treading action to undo this damage in my low-maintenance system. Here's an example of what many of my soil surfaces look like in the back 2 acres: http://www.flickr.com/photos/pjchmiel/7104720567
The only possible downside to this brush-scattering practice for me is in terms of mowing / scything / walking later, because at this point there are few delineated paths (trees are widely planted and have few understory plantings, yet), and I like to scythe stands of allelopathic knapweed, which I have growing everywhere. I've also scattered a lot of discarded Xmas trees around and have noticed that white pines in particular have put on much better growth when sheltered from north winds by a fallen coniferous brethren.
PJ, it looks to me like you're doing a great job with a flat, sandy site. You've probably already thought of everything I'd do, but on the off chance that I might share something useful, if I were working with such a sandy site, here are some things I probably consider:
ReplyDelete1. Establishing permanent beds and paths so I could pile on debris and let the beds grow mass instead of mowing. This would help grow more spongy root mass IN the soil instead of above it (mowing stimulates more growth above ground.)
2. Grow lots of "sacrificial" trees, shrubs and plants (but not within the root zone of any important trees. I'd likely go to a local park with dry forest and gather lots of seeds from pretty much any woody plants that would grow aggressively on site.
3. I might go heavy on drought-tolerant, woody Mediterranean herbs to generate a useful crop and woody mulch.
4. Try growing purslanes, lambsquarters, and sorrels (which can be aggressive or even invasive on sandy soils) because the oxalates they secrete in the soil will help protect your other plants from your knapweed. Then I would likely let patches of knapweed grow (but not seed) since that would work more roots into the soil.
5. Try a few "Wicking beds" for semi-intensive production.
6. Model my "mature" garden, (I'd aim 10 years in the future on that site) off of the location's historic ecology. I'd guess your garden is naturally on its way to Oak-Pine Barren (just on the edge of Dry Southern Forest) which I suspect would be the most productive ecosystem type (probably more annual bio mass than dry southern forest types) in terms of bio-mass and bio-diversity for a very sandy site in your "neck of the woods," right?
So, I'd aim for plant spacing and density similar to that ecology, and I'd probably go heavy on plants native to that habitat, at least early on. I know you already have a high percentage of these plants, but for those who might be reading in, MSU has a nice list if you Google "Oak Pine Barren."
Another idea, just brainstorming, would be to adapt the "banana circle" concept. Build a circular underground pond, about 2 feet down, with a depth of one or two feet. Line the bottom with betonite clay. Then fill the "pond" with lots of woody debris and compost to help absorb and wick the water. return the soil, then build a woody compost heap, or even a hugelkulture mound on top. Plant your trees in a ring around this, just outside of the pond area. This would give each tree access to high fertility and water, but minimize the risk that the roots would break through the pond and drain it. At the same time it would also ensure that the trees are planted in well drained soil.
ReplyDeleteSome great ideas, thank you! For the back 2 acres, I haven't thought much in terms of "beds" or even permanent paths up to this point (partially a lack of time for maintenance/attention/watering), the trees are spaced pretty far apart...eventually a lot of canopies will touch or nearly touch, but I may be dead and gone by then. The historical record says that 200 years ago my land was oak savanna, so I've steered at least part of it back to that, with a variety of widely spaced oaks chosen for sweet(er) acorn production on a dry site. The rest of the site should eventually feel more like woodland than savanna, but I expect to lose some trees to disease, pests, wind, etc., which should open up gaps here and there, at least in theory...but there will always be weed trees arriving as well, so it will need maintenance if it's not to become a closed-canopy forest.
ReplyDeleteI'd meant to plant more sacrificial trees, but got screwed 2 different times in trying to order Italian Alders for mass planting as N-fixers, so I've filled in with some cheapo trees from the Conservation District sales, as well as catalpas, locusts, cedars, and others that I dug up as seedlings, (along with herbaceous N-fixers like leadplant, wild / false indigo, prairie clover, and shrubs like autumn olive, buffaloberry, seaberry, etc). Many of my sacrificial trees didn't make it due to neglect, drought or animals, but scattering seeds around is a great idea. I've been letting any wild-seeded trees grow in the meantime, and hoping that more would show up as I don't mow and keep adding organic matter, but it's a slow process.
I love purslane and lambsquarters, though so far they've only showed up in disturbed garden soil and rarely elsewhere on the property. Sheep sorrel is fairly abundant, as is yarrow. I try to spare the yarrow when scything down knapweed. I've got some woody herbs (oregano, sage, wormwood, lavender) going in some areas, but should propagate more to plant out. Wormwood and oregano are pretty aggressive spreaders.
I've been trying to plant beds of appropriate native wildflowers and prairie forbs throughout the property, to act as a seed source to populate the other areas...I hope that takes off more in years to come. In the MI Forest Communities book, my land is currently kind of in between "Southern Oak Barrens" and "Southern Dry-Mesic Deciduous" (the area nearby used to be swampy before drain tiles, and there are lots of mesic hardwood forests close by, so given enough time, nutrient cycling and a lack of fire, it may go this route). One nice thing about my place is that there's water about 6' down, so if the trees can make it through the first few years and get their roots down there, they shouldn't suffer as much in droughts. But in dry spells, the soil can be powder-dry 2 or 3 feet down!
One goal for this year is to dig down to the water table (a small pond) and see what happens, i.e. for how much of the year it stays wet. I've got a couple of artificial ponds I've made but I'd like to try one with no artificial liner and see what happens. I've been encouraged by seeing some toads making use of my fake ponds.