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!

2 comments:

  1. Yeah agroforestry! As if you're not busy enough, any systems that you encounter along the way that you care to share in more detail would be greatly appreciated Lindsay! I'm working on some polycultures here in the Northeast but would love to know more about what people are doing in other parts of the world.

    Thanks

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  2. GREAT info! "Who'd a thunk?" is right!

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