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  • From: Dieter Brand <diebrand@yahoo.com>
  • To: permaculture <permaculture@lists.ibiblio.org>
  • Subject: Re: [permaculture] mediterranean orchards, terracing and fire protection
  • Date: Wed, 12 Dec 2007 01:48:54 -0800 (PST)

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


be peace <seed4peace@yahoo.com> wrote: Dear friends,
my name is nora and i live on a farm and a learning centre called axladitsa
avatakia in northern greeece on the peninsula of Pelion (www.axladitsa.org).
This is typical mediterranean climate with olive orchards all over the place
and some degraded left over mediterranean type of forest and lot of maquis
around. We have a land of 24 acres and a big part of it is a bit neglected
olive orchard and some overgrown areas that according to local knowledge have
been orchard and gardens before. we have just moved into the place last year
and are slowly starting renewing the place. there is few dilemmas that we
face:

1. how to keep clear the ground in between the olives - so far we were
turning around the soil with a tractor - shallow ploughing, but i want to
find a different method which would be gentler to the soil. the local
knowledge holds the olive for a very "jealous tree" that wont like other
things growing around it, hence the ploughing practice. i know about mulching
but the area is too large and mulch presents a fire hazard which is very
critical in this area. i have considered green mulches but then we would need
something strong enough to supress the omnipresent brambles and somthing
which gets harvested before the main fire season starts (june). Any ideas? It
would be also great if we could get a plant which is somehow compatible and
will benefit the olive and mitigates protection of topsoil for which olive is
a total disaster having no surface root system.


2. great part of the land is on a steep slope, the local practice is to
terrace it, i understand that the terraces have similar function as swales in
water retention - is that right? what would be benefit of swales over the
terraces? (or vice versa?) what is the maximum slope u can do swales on
without causing more erosion?

3. mulching - im very fond of mulching but here the locals are very
distrustful of the practice as they consider it a great fire hazard. in long
term - with retaining more water in the soil and cultivating the humus layer
- does the fire risk become less? can the fire risk be minimalised somehow in
the mean time? lets say with the drip irrigation under the mulch? any
experiences to share?

4. any fire protection/management advice or resources are welcome!!! so far
the two main approaches that i encountered are - clearing the land
periodically nevermind the soil. or burn the land - as previously "natural
fires" did. im conflicted about both approaches and i feel i need more
perspectives, more points of view to gain my own understanding

5. any greek pc contacts, please? or mediterranean? any resources relevant to
olive farming and mediterranean?

i hope to get some advice and im willing to continue sharing experience as we
learn adn experiment here. I would love to get in touch with other people who
have experience with olive farming and mediterranean ecosystems in general.
Thanx for considering my message!
peace&pace
norak



'Modesty is dangerous: If we believe we are here to do something, if in fact
we have the daunting task of turning around a system which appears destined
not only to degrade, demoralize and dehumanize us, but to destroy the
ecosystem in the process - we don't have time for outdated social customs.
You need to tell me what you can do, what you are good at, how you can
contribute to helping to make these changes. And i in turn need to tell you
the same. Anything less endangers us. Anything less leaves one of us
wondering why the other is not being clear, 'Are you unaware of your gifts?
Are you unsure of them ? Am i wrong in estimating your ability?' Paxus Calta





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