invoking the 48 hour rule: hugelkultur and contour

I was unaware that this thread existed... so I apologize for sending an email in lieu of posting here.

About 10 days ago I posted to a thread and I am still looking for an answer, some direction, or even additional resources. I pasted the link below and I edited the quote to contain the second question only because that is where I am really struggling to visualize.

https://permies.com/t/30879/hugelkultur/Cold-climate-hugelculture-contour-contour

A.J. Gentry wrote:I am very happy to locate this thread as I am really trying to picture what a hugel / swale cold climate set up would look like. I was just listening to one of the podcasts -- #228. Paul and Geoff Lawton are talking swales. Size and depth. And I think they chat on / off contour (maybe not). I wrote down that Paul said 8 - 12 inch depth for the swale in a cold climate. But I don't know if that was for on contour or off... or both.

I will post my specifics --
Slope is 10 - 15 degrees from NW to SE
Average annual temperature 52.8 F
Average annual rainfall is 39.4 inches. With 27.7 inches of snow. (I admit I am not sure how to locate how much of this falls during the growing season.)
I have not put the beds in yet, but if they run N-S they would be 200'. If they run E-W they would be 60'. (E-W would be contour) These would be pretty tall. The land has a lot of rotten wood from old trees. So maybe 4-5' tall.

Is there a way to both capture the water and let the cold run run downhill? These two things seems mutually exclusive to me. (Again a concept that is tough for me to visualize). If I were letting the cold air go wouldn't that mean I was off contour and therefore wouldn't be able to hold water? Should I even worry about water because of the rainfall in my area? Because of the size of the hugels and once they are in place for 2 years I won't have to worry about it anyway?

I realize that a lot of the process is a learning curve. But on contour / off contour seems like it could be a type 1 error so I am hesitant. If the answer is really just what is more important to my design cold run off or water storage I would be able to make that call.

Any insight would be appreciated.

A.J.

I am scrambling to catch up on a lot of things right now. I am hoping that somebody will jump on this and make sure that A.J. has an excellent answer.

A.J. Gentry wrote:
Average annual rainfall is 39.4 inches. With 27.7 inches of snow. (I admit I am not sure how to locate how much of this falls during the growing season.)

Weather data for Ohio: http://www.oardc.ohio-state.edu/newweather/ (Buff up on your spreadsheet skills and you can find our your average monthly rainfall for the past few years or so.)


My instinct would be to go off contour and let the rotting wood handle the water adsorption and distribution. That's a fair amount of rain.
Or maybe go with a mix and put on contour at the top of your slope and off contour half way down. This would hold water up high on the land and allow the lower stuff to shed it's cool air.

Just some thoughts.

Hi A.J.

While I can't give a personal experience of on vs off contour hugel beds, I can say that in the book Sepp Holzer's Permaculture he specifically advises against putting hugel beds on contour. His reasoning is that the first Hugel bed you put in will get all the water, and may eventually slide downhill, while the ones below it will not get as much water as they could handle. In wet climates, or climates that get a lot of rain in a short time period, this makes sense to me, especially since the way he does hugel beds is forcing earth to pile up with a very steep angle of repose, in contrast to a swale's generally more gentle slope.

Now if I've understood Paul's philosophy right, you should have funky wacky hugels that don't follow any particular contour, because that gets you a wide variety of microclimates. The hugel beds can then be inhabited by plants that love and thrive in those specific microclimates, meaning you can get a greater overall diversity of plants in, and maybe even plants that you wouldn't be able to grow in that place under different situations.

I would personally try things several different ways to understand which was best in my place. I can't speak to other people experiences, but I'd want to find out on my own by doing some test hugels in different places, and then going from there.

Now about capturing water and rejecting cold. I believe it's possible to do, when you look at the system, but I don't know if it's possible to do in one specific location. Let me explain. If you build a hugel that is shaped like an "~" You'll have one section which catches water and cold, and another that drains it. One of the many cool things about water is that it will soak beyond the area where it is (think wetting one side of a paper towel, how quickly it reaches the other side). So if you planted in the center of section that drains water, you'll have water nearby that it can suck up, but it won't be directly in a cold pocket.

Most of this is conjecture on my part, but I think it's possible, and I wish I had the space to try it.

Hi A.J. --

I'm not going to claim to have a firm answer on this, but I've obviously been pondering it same as you. Here's the conclusion I've come to.... If you put ia bed 100% on contour it becomes almost like a swale with wood in the berm. Yes, it would hold lots of water, but it also dams cold and makes less water available to down-slope beds (a 'run-off shadow' effect). If you run them completely (ie 90 degrees) to contour, you shed the cold air but don't get the benefit of nearly as much water capture. So my thinking is that the optimal answer is somewhere in between. Heck, we're trying to mimic nature, right? Do trees always fall exactly on contour?

The best hybrid I've come up with is to put the beds off-contour and also not to have each one be too long. Having them off-contour should help them shed the cold air while still letting them slow-down and capture a significant portion of precip. Any precip not captured by one bed should flow off the end and hit the next bed which then has a chance to soak it the excess moisture. I think exact angle off contour probably depends on amount of precip, the distance between bed, and steepness of slope -- I'd say let intuition be your guide.

I'm gonna lock this thread.

This thread is about discussing the invocation of the 48 hour rule. It contains a link to the thread that talks about hugelkultur.