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  • From: Paul Cereghino <paul.cereghino@comcast.net>
  • To: permaculture <permaculture@lists.ibiblio.org>
  • Subject: Re: [permaculture] mediterranean orchards, terracing and fire protection
  • Date: Wed, 12 Dec 2007 22:43:33 -0800

Thank you Dieter, your practical experience is much better than my book learning. Fire ecology predates capitalism, and is something to take very seriously (though building soil moisture is a good thing). It might be useful to find people who understand fire behavior in your landscape first hand who can talk about dominant wind direction during fire season, likely sources of fire near your property and how fire might move on your land based on landform and aspect. While your strategy is based on your parcel, fire operates at a landscape scale. Alignment of grazed pasture, or roads can also serve as fire breaks.

In our Washington state, USA dry-side forest I have spent time with folks for whom fire preparation has been a source of positive community building. We have even had some government grant opportunities for communities working toward defensible settlements -- there might be an opportunity to get some subsidy for a well developed plan. To live in fire country is definately a trick of biologically 'burning' your fuel load before you set your self up for a catastrophic burn.

Another thought would be to talk with climate specialists to better understand the future. 600-800 years ago during the midieval climate optimum, our rainforest region had landscape scale 'stand-replacing' fires that whipped accross the landscape consuming the 'fuel' accumulated in more moderate centuries... only indigenous non-capitalists as witnesses... something else to look forward to in global climate change.

Paul Cereghino
Olympia, WA

Hi Nora, I'm pretty much in the same situation as your are. We bought an overgrown hillside property in the South of Portugal 10 years ago. There are some olives, but it's mostly madrone and cork oaks, both are very typical of a Mediterranean landscape. They get by without water during the summer and usually recover after a wildfire. Seems you got all the heat and fires this year that we normally get here in Portugal. In the last 10 years we burned down once, a neighbour burned down twice in the same time. Even if we are not directly affected, we usually have to evacuate once or twice in most summers when the fires get too close for comfort. The heat and fires are nothing new, they always existed, what is different now is that many small farmers have given up their land which becomes a tangled and impenetrable mass of combustible material 5 to 15 meters tall. During the summer heat and drought, a single spark, for example one stone hitting another, can set it all ablaze. There is no way around it, one needs to thin out the undergrowth. You don't have to go so far as to practice a bare earth policy though. As you already noticed, it is part of Mediterranean culture (the same applies to the North of Africa) to rid the soil of all vegetation. This has a disastrous effect on soil humus. I have been experimenting with no-till and natural farming for a number of years. I'm still not sure that I will be able to come up with method that would allow this to be commercially practiced in a semi-arid climate like the Mediterranean. Anyway, I don't plough and keep the soil covered at all times with vegetation or mulch. Usually, I cut all the grass in the April- May period at the onset of the dry season. I leave some to cover the soil and use some as mulch in the garden or to make compost. It is best to keep the grass to 4 inches or less during the summer. Mostly, a fire will just burn through without doing much damage if there isn't much combustible material. I also cut the lower branches of the trees and shred them for mulching in the garden. If there is a space of 3 to 5 meters between a low grass sod and the lowest branches, a fire will usually not do much damage. If, on the other hand, your grass grows into low growing branches of trees or if you have a solid mass of bushes, scrubs and brambles, a wildfire can have devastating consequences. Around the house, I remove more vegetation and leave less mulch than in places further away. Instead, I use stones and gravel to cover and protect the soil. I use the existing terraces, but don't make new terraces or swales. Due to ploughing by previous owners, most of the topsoil has washed away, leaving mostly clay and rubble. Any soil disturbance, like ploughing, making terraces or swales, will turn the little topsoil there is underground and bring clay from the subsoil to the surface that will quickly dry out and crack in the summer. The best way of water conservation is to improve the soil by practicing no- or minimal soil disturbance and by adding all the organic matter to the soil that you can get. A good soil can retain some humidity for 3 to 4 months without rain even in the scorching summer heat. I cut down on irrigation by 80 % since I switched to no-till and mulching. "Green mulch" does not help against fires. Even supposing you have enough water to keep your land green during the summer, an advancing fire front will wilt and burn any green plant within a second, thus turning it into combustible material. The only way, as I said above, is to keep combustible material to a level at which a fire will burn through without doing much damage. There can be a number of reasons for ploughing under olive tress (for example controlling the larvae of the olive fruit fly), but, unless you see your soil as a
production machine fuelled by synthetic fertilizers, competition in orchards
is
not an issue. The soil needs vegetation to maintain and increase its
fertility.
The leaves from the olive trees are not enough. I have grass and weeds grow under my olive trees. Brambles are very useful. They are an indicator for good soil. I usually broadcast small grains and cover crops into the bramble and scrub land when we get the first autumn rains. Then, I cut/shred the brambles and
shrubs so as to form a mulch layer covering the seeds. If there is enough
humidity, the crops will grow through the mulch in a week or two, ready
to be harvested the following spring or summer. The mulch can burn of
course, but the fire fuelled by an inch of compact mulch is nothing in comparison to the fire that would have occurred with the 6 to 12 feet of brambles and scrubs before cutting and shredding. The mulch will
disintegrate after a while to form topsoil, thus again reducing the fire
hazard.
There is plenty more to say, but I have got to run now. Dieter Brand Portugal






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