Ok here goes.
We live in North East Spain - maritime zone 9a with about 400-500mm of annual rainfall. Slightly sloping 7 acres sandy and rocky (limestone) soil. Vicious winds in the spring, never freezes and can reach 40 in the summer.

Currently have about 200 olive trees, 15 almonds and about 20 carob trees. Solar powered well which produces a bit of water for house and irrigation. Aside from my various vegetable beds and house, I have about 6 acres that I need to repurpose.

New (to here) bacteria Xylella Fastidiosa is going to hit the Spanish mainland in a number of years and require that all my olive and almond (together with all citrus) are pulled up and burnt. The list of plants affected is pretty diverse and lengthy.

I would like to get ahead of the curve and cut down my trees for firewood now, before they have to be burnt, and replace them with a food forest.

Problem being that I have limited resources and water, and no clear direction. I have already mapped out swales and likely guilds but I am being overwhelmed by the scale of the project. This is a major repurpose operation of the land.

Would welcome any advice on any potential ‘watch outs’ or 'gotchas’ before I commit, and any general comments that anyone would care to make.
My requirements will be
Food for the house
A nut crop
A cash crop to replace the olives
Firewood
An oil crop
I have pretty much got the basics mapped out but am daunted by the scale and would appreciate someone telling me I am not mad.

Thanks in advance - Chris.

Have you spoken with your local nurseries about 'Xylella Fastidiosa resistance' varieties?

I would focus on grafting your existing orchards over to resistant varieties.

Hi there- thanks for the idea - had not considered that. Not sure if there are any resistant varieties available here - and is possibly immaterial as the recommended solution should an outbreak occur is to clear cut a buffer zone to contain the disease.

I am surrounded by olive trees on other farms and if one is affected then my trees, resistant or not will be sacrificed.

This buffer zone 'can' extend to 10km -  which pretty much nukes the local citrus, almond and olive industries locally.

Why do it all at the same time ? Why not bit by bit ? The problem is not there yet.
How about advocardo? Both oil and cash crop ?
Chewfa ? If you have enough water
Walnuts ?
Cork oak ? Use the acorns as chicken pig food .
Peaches apricots ?

Any chance you will be compensated for the trees if you are forced to cut and burn them?
If so,waiting for that might make financial sense.
A biochar retort could be used to create yeild from the required burning.

William Bronson wrote: Any chance you will be compensated for the trees if you are forced to cut and burn them?
If so,waiting for that might make financial sense..

I agree about if there will be compensation for clearing the trees to wait to clear them, but. Do you have any idea if such a policy is in place?

You can get started on planting other croppage now, though. If you will get paid to remove the other trees then wait for that event.

Advocardo, is that avocado? 

Thanks for all the inputs - much appreciated.

I had never heard of chewfa before.

I already burn for biochar so that was high on my list.

I doubt that there will be any compensation - there will be a stringent list of requirements which will be slanted against people like me. Three very large industries here are citrics, olives and almonds, all of which are vulnerable to the disease.

I will have to attack this piecemeal - remove the weaker trees  first as they are more susceptible to the disease and start planting to get a head start.

Thanks once again for the insights.

Just a thought Figs ! great root systems very hardy have you read the posts in this thread ? https://permies.com/f/121/desert

As for replacements,consider Quercus prinoides,the Dwarf Chinkapin Oak.
With acorns low enough in tannins to be edible right off of the tree, they coild be a nut protien and oil source in one. Acorn oil is said to be akin to olive oil.