Sunday, February 21, 2010

Lessons from Dalpura

I've spent the last week at Dalpura Farm, south of Melbourne, learning about silviculture - the design and management of forest systems with a goal of harvesting forest products for human use.

I am fascinated by the notion of forests as a resource base - forests play a crucial role in maintaining biodiversity, nutrients, and stability in an ecosystem. If managed carefully, they can also be a sustainable source of food, medicine, timber, fuel, forage for animals...the list of their functions goes on!

The thrilling part is that we as human beings can interact with and even enhance these forests, either by designing agroforestry systems (selecting useful species and maintaining them in a farm environment) or managing existing wild forests (by thinning, pruning, and clearing).

This curiosity led me to visit some well-known examples of agroforestry - farms that incorporate forests in to their production systems.

At Dalpura, I had the pleasure of working alongside two wonderful characters.


On the left meet David Griffiths of Geometree, a farm planner and tree specialist, who leads the forestry aspect of Dalpura. And on the right, sidekick Matthew "Matty" Fahey, a woodworker of Wood Mage, and an arborist and farmer who lives at and manages the complex workings of Dalpura Farm.

We spent the week thinning a block of eucalypt and acacia trees planted for timber; it's been a fascinating visit. Here are a few things I've learned.

1) Eucalyptus can be beautiful!


Those of us from California are accustomed to turning our noses down at the weedy "blue gums" that grow like mad monocultures on our hills. But if managed appropriately in the right environment, eucalypts grow straight and true, and can produce beautiful, rot resistant hardwood used for furniture, fencing, and framing in less than 30 years.


This is a kitchen that Matty built with Red Ironbark (eucalyptus tricarpa). Beautiful! Who'd a thunk?


2) Select species carefully - you can not force a tree to grow straight by pruning.

Just because you can harvest beautiful timber from a tree in the wild does not mean that it will translate well to a farm crop.

For example, while the red ironbark is a beautiful timber, generally it is not a straight-growing species. In the wild, you might be able to harvest 1 out of every 500 trees for straight timber. And you can not prune a tree to force it to grow straight. So if you plant a block of red ironbark on a farm, you will still probably only get 1 in 500 to grow straight, which is not a good success rate for a farm crop!

Here's what's left at Dalpura of the red ironbark experimental plot.


A clearcut agroforestry plot is a pretty depressing sight.

3) Forestry is not necessarily regenerative.

Planting trees is generally thought of as a good thing, a no brainer way to improve any piece of land. But just because you plant trees does not mean you are building soil, or increasing the fertility of the land. In fact, at one of the farms in the area that I visited, the erosion in the agroforestry plot was deplorable.


Here's a picture of me (I shouldn't be smiling! it's not funny!) acting as a measuring stick against the sunken piece of land under a forest at the
Bambra Agroforestry Farm
. The soil was totally bare, with no ground cover – not at all what you would see in a healthy forest system. The lack of topsoil has caused massive erosion in multiple places on the forest floor.

In addition, often vast swaths of native forests are chopped down to plant timber monocultures.



In this photo you can see a monocrop of pinus radiata which is widely used as a framing timber in Australian building industry. Diverse and healthy forests must be cleared to make way for this monocrop. There's nothing regenerative about that.

4) Scale matters.

In huge monocultures, agroforestry can be destructive. But small forest systems designed into farms can provide timber and firewood for farm use, lend shelter and windbreaks for livestock , all while creativing habitat for native birds and wildlife.

We visited the sheep farm of the founder of the
Otway Agroforestry Network, which exists to promote agroforestry to farmers to see a great example of a well-functioning system.

This forest strip was healthy and well-maintained. The trees were pruned straight so they would be valuable as timber, and the sheep happily flocked towards the protection the trees provided.

I'm eager to experiment with incorporating timber systems into farmland back home, applying these general lessons to a different climate with different species. Should be a fun challenge!

This weekend I'm heading to the Food Forest in South Australia with friends Michelle and Rob from Canada, then back to Melbourne for a 10 hour ferry ride to Tasmania! I head on to Fairweather Farm to help friend Trevor and family renovate their organic tomato farm in to a showcase of water harvesting, soil building, polycultural, regenerative agriculture.

More soon!

Sunday, February 7, 2010

Closing the Loop

In a world where less than 1% of the planet’s fresh water is available for human consumption, it is curious to notice how people in overdeveloped countries choose to utilize precious water resources.

I often wonder what our grandchildren’s children will think of industrialized cultures; it is hope that inspires me to imagine them laughing. “Can you believe it?” they’ll say, holding their bellies and bursting with amusement at the ridiculousness of their elders. “They used our precious fresh water to flush their SHIT away!”

Over 884 million people globally lack access to safe water supplies – that is approximately one in eight people living on the planet whose water has been contaminated, generally by human excrement. In fact, over 5,000 people die worldwide everyday from drinking or bathing in water containing contaminants.
[i] And we in the U.S. use over 5 million gallons daily just flushing away our waste.

From a health and a resource perspective, it’s hard to imagine a more inefficient system than a water flushing toilet. It contaminates water, and wastes our “waste.”

Anyhow, I digress. This blog posting was inspired by thechore of the day at the Permaculture Research Institute.

It was time to empty the composting toilet system, and I eagerly participated, curious to see how human “waste” could be utilized as a resource – quite a feat for our fecophobic world.

Here’s a quick rundown on how the composting toilet works.


The composting toilet system at the farm is simple; a normal looking bathroom, with two normal looking toilets. Just like any toilet, you pull your pants down, and empty your delivery into the hole that is attached to a chamber below.

(In industrialized cultures, that’s where your relationship with your poo ends – instead of taking responsibility for your shit, you simply flip a button and send it downstream, confident that someone else will take care of it, somewhere…).

Once the delivery is executed (whether yellow or brown), you add a scoop or two of sawdust, a carbon-based material that aids the decomposition process and helps balance out the nitrogen so that (smelly) ammonia isn’t released.

And people keep pooing away in to the chamber below, until it’s full. Then it sits for a few weeks, and meanwhile you switch to using the other toilet. If used properly with the right amount of carbon added, it won’t smell and won’t attract flies.

Simple as that.

When we went in yesterday to empty the chamber, my curiosity had mingled with a bit of dread. But I was determined; I had my gloves on and my nose plugged, prepared to feel the morning’s oatmeal churn…



Alas! I was shocked (dare I say thrilled?) to see that in less than four weeks, the excrement of fourty people into a chamber had turned into a rich, humus-looking, stinkless mass - unidentifiable as human waste.



(Fellow toilet cleaner Dave, pictured below, agrees).


Granted, it had not yet heated up to the process of destroying all of the potentially dangerous pathogens found in human excrement. That requires a heat of 50-55 degrees Celsius for several hours, easy to accomplish in any hot compost pile. Once the humanure has been decontaminated through a composting process, it is essentially a carbon sponge that can act as a substrate to grow beneficial microorganisms for the soil – a valuable resource for any backyard garden.

Though I am generally in favor of decentralized systems, where we can personally observe how our actions impact our local environment, I’m not necessarily saying that everyone must process their own waste on a household scale.

In fact, there are plenty of examples of sane ways to process effluent on a local scale, such as the
Ecological Wastewater Treatment Plant in Arcata, California. The facility utilizes the microorganisms on a plant's roots to break down pollutants in the water.


Or the Living Machine concept developed by
John Todd which also filters sewage solids out of water using plants and their associated bacteria.


Marin County (home sweet home!) is even in the process of piloting a very progressive compost toilet program.

These are all potential models for a semi-centralized, but ecologically sound, waste processing system.

Nonetheless, it’s pretty empowering to know that we can safely and effectively process our own waste, conserve our water for more precious uses, and convert “waste” from a problem to a solution.

And to pick up from my last posting...I feel one step closer to my steak dinner now that I know my poo fertilized the soil that grew the grass that Red ate!


Team Humanure: Mission Accomplished!



[i] http://www.water.org/


For more titillating reading on the topic, you can download (for free!) the entire PDF of the Humanure Handbook. A good book to have on hand in the bathroom. :)