Olives - pruning etc.

I have a question with regard to olives and pruning and soil protection.

We have an olive grove with some 2-300 trees. The soil underneath is destroyed - utterly (experts have viewed it and say we are down to stratum b - no top soil, no soil - in fact some places we are down to bedrock). The trees have not been pruned, or at least most of them haven't been pruned, in some 15 years. We need to prune them, we cannot get around that, because there are wild olives enclosing most of the trees, so that we can't get to harvest the agricultural olives.

We are now discussing what to do with the cuttings.

My husband recently had a discussion with Rosemarry Morrow - and her suggestions was to not prune at all, but leave the wild olives as is - to protect what ever soil there may be left (but that will leave us without an income next year...). Alternatively she would leave the cuttings on the ground - as is. She says that she would hope to slow down at least some of the water running down the mountain by doing so.

I understand what she is saying, but as we live in an arid area (Andalucia, South Spain) - the cuttings will not compost (I know because the few trees that have been pruned the last 15 years have their cuttings lying around on the ground and they are not decomposing). I am afraid that the cuttings will pose a fire risk (we've had some pretty ugly ones down here last year).

For now I have let my neighbor take his goats in, and they will eat the leaves off of the cuttings, and he will leave the branches. I was planning to collect them for firewood later - and my husband and I are now discussing whether to collect them all, or just collect them on an ongoing basis and leave the rest to function as miniature gabions (in some places across our land some one has put old cuttings into the arroyo to function as a gabion). Or to gather all... or to chip it up and leave under the trees...

In the long run we will plant oaks on the top of the mountain, and make terraces between the olives (I think) - but the question is, what to do for now...

Hi Dawn,

Be patient with me, as I may not have understood.

You are asking if you should prune, the answer is yes.

Fire load is a huge issue in arid regions so just leaving everything scatter around is extremely dangerous, especially if this is your working landscape and livelihood.

Your gabion concept is wonderful, and I understand that composting in your region is extremely different than what most folks would understand.

hope that helped.

j

That's what I thought. So prune, put the cuttings in the arroyo or gather it? It that what you are saying?

Dawn - maybe you could prune now and leave the cuttings around the trees over winter. They will help to protect the soil during the wet season, and also the leaves will slowly fall off, and they may even start to rot down in the moist, shaded environment of the cuttings. Then, in the late spring, before the hot, dry, fire-season is upon us, collect the woody cuttings, leaving the half-rotted leaves behind. You get the firewood, the soil gets protection from erosion, and the leaves should start to return their nitrogen to the soil.

Our neighbours were very concerned that we didn't 'clean' around our olive trees every year but they are now content if we tether the donkey to each one for a few days to keep the 'weeds' under control. The weeds are kind of pretty, though...

That is a really good idea! Maybe let the hosts in when the weeds are running really high, before they get really dry?

But won't the goats leave most of the nutrients if I just let them eat the leaves?

Hello Dawn,

Burra M. is giving sound guidance it the last post. In the spring you will do a little bit of everything, gabions in the aryo, gather some, and a multited of other applicable applications for your prunings. Hand carved olive wood spoons are rather nice and can fetch a fair price these days.

regards,

j

Seems like your first priority should be to slow water, if erosion is occurring. Swales, stone gabions, branches, anything is better than nothing.
A close second would be to get as much organic matter on the ground as you can. Are there any sources of affordable material you can bring in? You might need to be creative, if the obvious choices like wood chips or straw aren't available in your area. Are there any waste products from agricultural processing that you could access, e.g. press cake from olives, nuts, fruits?

Maybe compost tea would put some life in the prunings and help composting it.

You should take a look at Agroforestry News vol 11 n°3 by Martin Crawford, there is a one page article on a coppiced olive orchad on a 10 year rotation. You get 85% of yield wrt to the conventionnal pruning, but 10 times less pruning time.

The neighbor has offered me the manure from his goat stable, I just need to find a way to transport it. I have also thought of asking my green grocer for his scraps.

It would take a lot of worm tea to compost the wood in our climate, it is simply too arid. Once we have a proper food forest maybe, and swales etc maybe, but not now.

I know we need to swale it. But sealing will take machines, because digging by hand takes far too long... The ground is too hard (we have swaled a little piece of land behind our house - that has taken us almost half a year (only working after my husband gets off from work).

Hi Dawn,

I feel your plight and understand it. Most folks, I believe, that follow Permies are not familiar with the challenges and differences of Permaculture in a desert or extreme arid biome.

What type of water production do you have for your property, if any? If you do have some, have you started any type of aggressive mass composing? Why don't you have goats of your own? Also, if you have no heavy equipment, do you have a means for purchasing a borrow or work goat?

Water production?

I rains quite a lot, just only in the winther, soner exocet
To collecting the rainwater off our roof (and any roof), aside from that we have three wells and a water mine.

We don't have any animals there yet, because we don't live up there indtil end December. We have simply been so busy building the house (not building it pursernes but managing a build, full time job, plus home schooling two kids has been enough - in between that we havne swaled a part of the ond behind the house).

I just have to og back to see what you wrote

No we haven't started any aggressive mass composting - we have considered it, but also considered that it would be to water intensive? So we do have plans of using animals as our composters - chickens, goats rabbits, maybe a donkey, maybe worms. But we also want to start small - to not spend a lot of money on stuff we know nothing about.

We have been given a goat (male though) if we want, but we can't take care of him yet, so we turned him down (he was born yesterday and would be bottle fed) - we will get some again next year, they don't want the males And five chickens, and we will steal some feral rabbits from a nearby park soon.

Well, I can't really say anything in regards to fire hazards, but in a climate like that the absolute #1 most important thing is to get some contour/keyline swales installed in regular intervals all across the property. The difference you get in water management (and for soil building) is like night and day, and you can plant things in/near the swales that would be difficult or impossible to grow otherwise. You can make them pretty easily with a laser level and a standard moldboard plow.

Thank you - I know swales are all important, but as i said, swales will have to be dug by machine and we will wait just a little before we get the full on digging going because it will be big and expensive (so we want to do it right the first time). But hey will go in, that is for sure

I once went to Mark Shepard's place and he uses a double bottom plow to make swales. If you can borrow a tractor, and have your on-contour stakes already in, the swale making doesn't need to take so long or be expensive. I would personally do the swale plowing in the fall, reseed the flop over of soil left by the plow, and watch it grow in the winter rains. Mark gets about 40 inches of rain a year, and plows about every 5 yards or so if I remember right. He also uses keyline plowing, which has a book written about it. Another strategy that he uses is a subsoiler. It opens up the soil so that when rain hits the soil the rain goes deeper, instead of sliding off of hardpan.

Soil building/water retention

Have you looked into vetiver grass? It is used in hot climates to make natural terraces and prevent soil erosion. You make a hedge of the vetiver along a contour. As it grows it thickens up into a bushy clump a foot or so wide but with a very dense set of stems and an amazing root system that can reach many meters into the soil.

When you get a rain event surface water carrying sediment and plant litter hits the grass hedge and slows down, gradually trickling through. As it slows down the sediment falls out of the flow and gradually builds up the soil level behind the row of vetiver. As it is also collecting plant matter over time you will begin to collect a more fertile and water retentive soil.

The grass itself can be cut once or twice a year (using something like a hedge trimmer) and the blades can be dropped on the uphill terrace side to contribute to the mulching and soil.



In this image you can see the sediment collected behind the hedge and the original darker soil line. The terrace now becomes an area for water infiltration and storage, instead of runoff, and is now sufficiently level to plant other crops.

Pruning Olives
In know very little about olives, but I agree that simply leaving prunings on the ground in a fire hazard area doesn't sound sensible. I'd take what is worth having for fuel and other uses then look into chipping/shredding it on site. A deep layer of woodchips does wonders for moisture retention and soil building.

Another thought - if you already have wild olive trees well established could you look at top grafting them to set a more desirable fruit crop? I know you can do this in other orchard systems and the wild root stocks are already well established - this would be much easier than clearing and planting new trees and you can do it with nothing more than some scion wood from a desirable tree.

I can't possibly get a tractor up here but we have been thinking about a small two where's tractor or something to dig swales.

The idea with the grasses are really good - maybe a combination of the two suggestions: Plow on continuar and then plant vetivir grass on the berms. We're also been looking at the small palm bushes - they are great for growing terraces - they actually funktion that way naturally in the landscape down here.

I think we will get a compost grinder or some thing on those lines and grind the wood not suitable for fire wood or crafting into a mulch.

Our neighbor has actually cut most of our trees now - and in some aces the wild olives have all but out competed the cultivar - there he has left one you strong wild olive next to the old half dead one, with the intention of grafting to cultivar onto the wild tree later on.

We just have to keep reminding ourselves that this is a long term project We want to do every thing now, and we can't - not with 6 ha, one working full time else where and two home schooled kids. It simply just is not possible.

I think you may be duplicating effort planting vetiver on tractor dug berms. Save the tractor for areas it can work easily and consider vetiver hedges on steeper slopes. Hand planting in rows is quite easy, but you will need to plant during your wet season to help them get established.

Berms along your swales will be good for raising new trees.

Ok - Thank you for the advise

Hello Dawn,

Only now have I seen your post and it's been a while since it's here. What have you done?

I also have some 300 olive trees, though in a less prone to fire region: Douro. But I totally understand fire is a main issue to you in Andalucia.
Nevertheless, I believe the underneath concern is having a profitable production. Since olive trees is generally going through the same problem a bit everywhere you, like me, is looking for different ideas to correct ways of doing. Something, or a lot of stuff, must be wrong if our land is going bare.

The olive trees produce best with "half" sun exposure, so yes, you should prune some so that most of the trees get some light going through.
We're not getting sanitary problems with the olive trees here for quite a few years which makes for one less problem: no pesticides.
We struggle with the same rainy winters and long dry summers.
We also have sheep pasturing.

Leaving tall grass or olive tree branches on the ground is really explosive for fire. Olive tree wood is very hard to burn, but once ignited will consume itself slowly igniting again very easily. Olive tree leaves are the most dangerous part: they are full of oil and burst into big flames in a second. So, if you don't get lot's of moisture, leavin branches or tall grasses is a sure path to disaster. And we had proof of it in my cousins land (though warned) where he left too much grass, turned dried in summer, and... he lost more than 500 olive trees.

My olive tree land has some slope, so we did a swale rather uphill to start collecting and retarding the water. We're about to do a second one with huggelculture more or less in the middle of the slope. We'll be filling it up with the prunnings and some manure. And we'll keep doing it if we get results we look for.

As for the sheep, they'll be out for some time. Later, for them to enter I'll have to have a talk with the sheppard. I believe he's one of the main reasons we have so little soil and wild plants. He brings the herd to pasture the plants are hardly coming off the ground. They don't have time to grow and get shopped several times each year. This treatment is worse then herbicides for them. But that's how everybody is doing here, and mabe that's why everybody has the same problems.

Also, I'll be plowing this year at least, once, on contour, so that the grooves help retain some more water. After these actions were taken I'll have to go with the flow, rethinking the situation though not expecting results in the very first year.

What have you done / is doing?

Well right now our neighbor the goat herder is pruning the trees and the goats eat all the leaves off of the prunings. In march when he finishes his work we will collect the firewood and the we will decide what to do with the cuttings we can't use for either that or crafts.

Wrt swales we are biding our time and observing the landscape. As I said there is no top soil - actually there is no soil at all... And the cliff is cast - so any water will drain away in minutes - well the places where it isn't clay...