In today’s letter:
- A little lesson on how the legendary farmer, Sepp Holzer, builds abundant ponds. Ponds that produce food and income.
- How the Chinese wheelbarrow and paved paths “saved” China’s economy after its infrastructure collapsed. It’s also a neat bit of technology.
- Plans for a DiY aquaculture system that allows you to grow lots of algae at home, and some ideas for what you can use that algae for.
Request: If you know someone who should be reading this letter, please share it with them. Or if you are working on something that seems to match what we do, share it with us.
Abundant ponds for fun, food, and profit
Sepp Holzer, the legendary Austrian farmer, has a saying, “water is life.” He believes, strongly, that water management is central to farming and if you don’t actively entice water to spread itself around and stay for a while, you are missing out on a big part of farming.
One of the ways he entices water to stick around is by building lots of ponds.
However, the way Sepp builds them, these are much more than simple ponds. They are abundant ponds. Ponds that produce plentiful amounts of food, year round and improve the surrounding ecosystem. They also provide him with a substantial amount of income.
Here are some of the things he recommends (see Sepp Holzer’s Permaculture for more):
- Site your pond where nature wants it. It will save you lots of effort in the long run. Study the topography. Analyze the soil. Look for natural wet spots. Get professional help if you need it. If you do this, there is much less likelihood that the pond will leak or slide.
- Don’t try to force the pond into a specific shape. Let the topography dictate it. Make sure it includes deep (more than 3 meters) and shallow ends. The shallow end has warmer water and can be used as an entry point for swimming and as a place to grow aquatic plants. The deeper end balances the temperature of the pond and provides fish a place to and/or hibernate over the winter. Make sure the drop off between shallow and deep is steep (it’s a barrier to invasive plant growth and will prevent the pond from being overrun).
- Build the walls of the pond by dumping the soil you dig up in tall piles. You’ll find that the fine material you want for the wall piles nicely while the larger material will roll away. Pack these piles down tightly with an excavator. Add islands if you find them useful or aesthetically pleasing.
- Once you happy with the pond, seal it. Don’t use a pond liner. That makes your pond brittle. Instead put some water into the hole and let it rise to 30-40 cm. At that point, Sepp inserts the excavator bucket about half a meter to a meter (depending on need) into the bottom soil and vibrates it. This seals the bottom in a way that allows plants to grow freely.
- Finally, for long-term flexibility, insert a standpipe drain at the lowest point in the pond (assuming the pond is situated in a way that allows you do drain it from the lowest point). The standpipe drain looks like the letter L, with the lower portion going through the wall of the pond at the lowest point and the top at the water’s surface. If the vertical portion is added in segments, you can easily set the water level where you want it, or periodically drain it to rapidly harvest fish and plants. A good safety tip is to insert and overflow valve for torrential downpours at the top of the pond.
- Banks and shallow areas can be modified with stumps and large rocks to improve aesthetics and pond performance. Rocks are particularly good are increasing water temperatures, so use them liberally if you want to raise warm water plant and fish species.
The Chinese Wheelbarrow and Paved Paths
What happens when the money and political will required to maintain an extensive road network evaporates?
People improvise. How? The adapt by building new methods and new technology.
Here’s a great example (thanks to Kris De Decker) of that. Around 300 AD, the Chinese empire supported 25,000 miles of roads, which is about half of what the Romans built. Like the Roman roads, these Chinese roads fell apart rapidly, after the finances required to maintain them evaporated.
To compensate, communities and enterprising individuals began to build narrow, more easily maintained paved paths. However, these paths were too narrow for anything but foot traffic to navigate. Again, innovation bloomed and the Chinese wheelbarrow was born (it started as a military innovation that allowed rapid troop movement and served as a lager for infantry).
The Chinese wheelbarrow, unlike the western wheelbarrow, acts like a pack animal. It carries all of the weight put upon its large central wheel and axle (in contrast to the lever of the western wheelbarrow). The person pushing it is merely directing its course and providing the force to propel it forward. This configuration allows the wheelbarrow to gain stability with speed.
The result? A wheelbarrow that can navigate narrow paths with ease while carrying up to 400 k of cargo at a running pace. Essentially it’s the perfect low-cost, high-speed method of getting product from river transports to inland destinations given rudimentary infrastructure.
If you like this topic, there’s lot more about this wonderful bit of technology in Kris’ article. Please give it a read.
Growing Algae at Home?
Most people think that algae is a persistent pest. If you own tropical fish, a pond, or a pool you understand how fast it grows. However, it may prove quite useful. How so? Here are a couple:
- It’s used in lots of Asian (Chinese primarily) cuisine. It’s also VERY good for you (omega 3/6 fatty acids).
- There may be a way to turn into a high quality fuel in the future. That’s still in motion.
- It can be used for “green” compost material and as a fertilizer.
Estimated Construction Time: 4 Hr
Required Skill Level: Simple Power Tools
Simple wood frame and tubing (cast and extruded acrylic tubing). The completed tubes are dipped in “plastic dip” sealant (make sure none of the sealant leaks into the tubes).
Here are the low-cost air pumps used to keep the water in the tubes oxygenated.
Jared’s completed reactor looks like this. It can be tilted off the vertical to get sunlight.
If you know of any useful way to grow or use algae (other than as a food supplement or composting material) today, let me know.
That’s it for today.