A first post here. First an intro, then a plan summary, then a question. We have a small homestead (7 acres) that we have a cider orchard started on (Don't Quit Yer Day Job Orchard) and are finishing our house. What fun to raise children, build a house and try to farm at the same time. Really though we are blessed with all of it. We have several acres on a sloping hillside that was logged about fifteen years ago. Currently it has some usable timber for lumber, and of course we will use everything on it in the hugel beds once we get the swales made. The summary of our plan for the first part of land to use the swales is to install the them, plant fruittrees, understory plants, and then get those going for at least one year before bring the pigs into the area. Also, we plan on only about four pigs maximum on this two acre area. Not sure if we'll section it off into smaller paddocks but that would seem likely. The goal of feeding the pigs is that once the trees are producing we will be sharing much of the fruit with them. I think Sepp would be pleased.
Here's the question, eventually: in his Permaculture book, Sepp goes into how swales alone are fine for gently sloped terrain but on steeper terrain you'd be looking at forming terraces, then installing swales on the downhill side of those. Considering that, I'm interested in asking someone here who is experienced installing terraces and swales who knows what percentage grade is sort of a recommended practice for installing these terraces. I understand that each site is different as are soil and rock combinations. I should also include that where we're at here in Appalachia, zone 6b, we have a a lot of sandstone "tumbling loam". There is a lot of rock and while we get 45" of annual rainfall (excellent), the rocky soil drains pretty well. How well I couldn't tell you. Rainfall does run off at a certain point as it sometimes rains for d-a-y-s. A good problem to have. All the more incentive to build a good system for water retention. Really looking forward to it all.
It might help if you estimated what your drop in elevation is where you want to install your swales. How many feet does the elevation change per say 100 feet. The swales I installed are on a gradual slope of about 7 feet drop in elevation per 100 feet. Knowing this someone might be able to give you some advice.
Location: SW Virginia
posted 5 years ago
Thanks. Yes, the rise over run becomes steeper the farther up the hill. Instead of percent grade I'll use a simpler example; for this example 1/5 equates to 1 foot of rise over 5 feet of run. So on our site the base is about 1/6. At the top it's probably 1/2. Hope that helps.
I realize your question wasn't about the pigs but that's what I know and I can warn you NOT to plan on pasturing the pigs in your orchard. Their feet are natural "compactors" & they rub. Man-o-man, do they rub even the bark right off some mature trees. So plan on just running them through for downfalls.
For terraces, it will be more a matter of how wide you want the flat(ish) areas created.
While you are laying that out, you will see how tall your retaining walls will need to be to create the terraces.
In the Andes, the Inca built many terraces, most are from 5 to 10 feet wide.
These all have rock retaining walls and are quite magnificent to see in person, they are awe inspiring when you use the steps carved into the living rock of the mountain.
You described your land lay fairly well, using that information, I would be building terraces from the top all the way down to the point where you have a 1/5 rise over run.
At that point, swales would work pretty well.
My land has a rise/run (on the south face) that is around 1/2 (it varies from 1/2 to 1/4).
I have been putting in hugel swales simply to slow down the water, but these will also be used as the basis for where the retaining walls will be placed when I get to terracing this slope for part of my orchard and vineyard.
The other side of the driveway will also be terraced and those will be where I plant my corn, barley, oats, and other grains.
I have a nice slow slope that faces north and on it, the swales do a much better job than on the south face.
By the way I live on the top of the ridge, since that was the easiest area for building living quarters for us the chickens, goats, pigs and rabbits.
We are on fairly steep mountain terrain. We have little in the way of flat ground, other than what I have created. Long ago I observed that over the centuries soil naturally built up behind stone walls to create small terraces. This also happens behind tree stumps and behind logs when trees fall across the slope along the contour lines. The actions of frost, hoof, wind and rain all tend to drive soil downhill until it hits resistance. The result is terraces.
Over the past 26 years I've been building fence lines along the contours to take advantage of this effect. This is how many of our farm's terraces are formed. A big part of why I did this was to capture water that otherwise flowed down the mountain side taking nutrients with it. Now the water soaks into the ground and our soil improves in quality as a result.
I like to do double fence lines between the pastures. This creates a buffer zone that is a seed reservoir for the pasture. The two fences are typically about six feet apart. I plant fruit bushes, fruit trees, nut trees and forages that need some protection in these lines. I setup the fences so they're creeps allowing in the smaller animals like lambs and piglets who then clean up the fallen apples and such. This keeps the larger livestock off the trees and root zones. The larger animals cleanup the apples and pears that fall outside the fenced zone into the pasture and benefit from the moving shade.
I've also done some larger terraces by using a track hoe, a bulldozer and our tractor's backhoe - the fast but expensive way. With infinite money I would do more machine worked terraces. I do the fence line ones as my long term tool.
He covers swales (berm and basin), terraces and the like including the best situations for each. I was able to get a copy from inter-library loan, but found it worth buying. He goes into slope assessment and all that as well.
Also a big +1 on pigs rubbing on things. I recommend planning to fence them off of the swale tops if you can.
Location: Mountains of Vermont, USDA Zone 3
posted 5 years ago
siu-yu man wrote:Walter, do you have a photo on your blog that shows your double fence contour technique? if so, could you please share the link?
I haven't made it the main topic of any article, yet, but it is discussed on the side in several articles and there are a few photos scattered among these articles that show the terrace edges, some bulldozed, some built up naturally, and the fence lines:
It is something that has evolved over the past 25 years or so here at our farm starting with the simple observation that when a tree falls in the woods and nobody's there to hear it the soil builds up behind the tree to create a little terrace, especially if the tree falls along the contours instead of across them. This lets water soak in and keeps the soil on our land. Later I added the second fence line to keep animals from breaking down the terrace edge which is what would otherwise happen in time. I then observed that this created a margin, a buffer zone, where reserves of plants could grow, kept the evil sheep off the apple trees and kept sows and boars from separate herds from fighting across a fence line. So the technique evolved over decades. We have done a little bit of machine work to build terraces but mostly it has been the contour fencing technique - slower but cheaper. With more money I would use machines more. With more time I would use fences more. The last one shows a pure contour fencing lane terrace which is about 12' wide and then there is a 4' reserve fence area up hill and another downhill of it. Sometime I'll do an article about the double fence lines as quite a few people have asked. It would be interesting to compare older and newer ones from over the decades. On my to-do list.