Sunday, October 21, 2012

Final Design Part 1

It's the final stretch after months of study to complete my Permaculture Design Certification course. I have to come up with a final design that meets the standards set by the International Permaculture Institute in Australia.

To help me remember everything, I've made a sort of flow chart, breaking down each task into doable sized chunks. It really gave my brain a rest, so I didn't have to continually roll through the process every waking moment (and lots of sleeping ones, too). The orange and green outlines indicate what is done already. Details below.

The design starts with lots and lots of notes, on both sides of the paper, a printout of Permaculture principles (to guide the process), and a map. The mapping process consists of making a rough sketch of the area, then taking a baseline measurement along two or more convenient points (like two corners of a building or fence line). From this line, two measurements are taken for each additional point at the site and then converted to a scale that would fit on a piece of paper. I found that for my site, if every inch was eight feet, it fit almost perfectly onto an 8 x 11 sheet. (It's just slightly off. You'll have to imagine a quarter inch wrinkle somewhere on it, which comes out to two feet in real life. Better an extra two than two short!)
The mapping process started off with more than one frustration, but when I decided to round to the nearest foot, thing got a whole lot simpler. I used a piece of string and tiny pieces of tape to find the points from the baseline (and other points from those points). Mapping a point works quite well when measurements are taken from two known points at as close to right angles from each other as possible. The end of the string is taped to the first known point. Then a second piece is placed along the string at the scaled down measurement from the known point to the point being located. A third piece of tape is placed at the correct distance from the point being mapped to the second known point. This is then taped to that point on the map. The correctly mapped point is found when both legs of the string are pulled taut at the place where the middle piece of tape is. Most of the time, a compass is used to make arcs on the paper from both known points, and the correct point is where the arcs intersect, but I didn't have a compass so I improvised.

Here, at last, is the completed base map, including the permanent elements to remain in the design.

After the base map is completed, and copies made, an overlay (using clear sheet protectors and permanent markers) is made to show the directions of seasonal sun, shade and prevailing winds. This sector map helps to analyze the site so that these energies can either be put to best use (such as planting a sun trap- a u-shaped shelter belt to create a microclimate for cold sensitive plants) or blocked (such as planting a windbreak).

The next energy path to map is water. Water is life, and there are lots of tricks in permaculture to make the water stay around longer, eliminating the need for irrigation, especially when it depletes deep aquifers. But first, we have to map the contours. Here is simple device, called an A-frame level, that can be made for almost nothing. Two poles of equal length are cut (mine are 6 ft.) and lashed at the top. A cross piece is lashed at the exact distance from each end. My cross piece is about 3 ft. long and lashed three feet from the bottom of each leg. A rock tied to a string hangs below the cross piece to indicate the center. To find the exact center, the level is placed on as flat a surface as possible and a mark is made where the string comes to rest. Then it is turned around, placing each leg in the exact spot that the other one rested on, and again marked. The true center is right between the two marks. Once calibrated, the level is ready to be used. It is walked across one edge of the site to another, keeping one leg in one place while the other leg is moved around until the string rests on the center mark. Flagged sticks are driven into the ground to mark the points where the legs rest, and then the first leg is swung around to the other side, keeping the second leg in place this time, to find the next spot along the contour.

Here is a marked out contour line across the site. I tried to embolden the blue flags a bit to make them easier to see.

Time to map the contour lines. This method does not give the differences in elevation between the contour lines (another homemade level, called a bunyip, works for this), but an A- frame suits my purposes here. I just need to map the direction of the water flow. I also included an estimated location for the buried water line that goes to the spigot, and the buried drainage tile we put in several years ago under the two raised beds. The area used to be quite soggy, but it has dried out a bit over the last few years as topsoil has been built up and drainage improved (one of probably several factors). After mapping these, I traced them onto another overlay.

 Below is the base map with both overlays showing sun, wind and water sectors.

 Next up, soil test results. If you can see the contour map close enough, I marked three locations where soil samples were taken. They were placed in quart jars, topped with water, and shaken. Heavier particles fall to the bottom while lighter ones settle towards the top. When it finally settles out, I'll be able to get a good idea of the texture of my soil. I am also waiting for an inexpensive ph tester to arrive. Then I'll document the results. Until then, I'll keep studying what I've got and hopefully it will not be long until the new design is born.

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