Combining buried logs with mulch/compost pits

Hi everybody

Thinking about my unfertile patch of land in a mediterranean climate (which by the way within decades will be desert due to climate change forecasts), I was wondering about the following combination of methods:

Dig some pits, around 1x1m, 1m deep
Put watered tree logs in the bottom
Fill the pits with organic matter, compost, horse manure etc
Put a mulch layer on top
Put drip irrigation into the pit

Plant fruit trees around the pit, and repeat the above process yearly as the material decays and loses volume.

Am I right that this would greatly reduce the amount of irrigation water used, and it would give my trees a good source of nutrients?
Am I right that the trees in need of nutrients, would get them from the pits, and the ones happy with poor soil, would stay with their roots on the poor soil?
At what distance would I plant the trees?
How many trees can one such pit feed?

Thanks in advance!

Lukas Rohrbach wrote:

Thinking about my unfertile patch of land in a mediterranean climate (which by the way within decades will be desert due to climate change forecasts)

I don't have answers to your questions, but your post reminded me of a set of hopeful stories that I recently came across about reforestation.  The first one is titled "Holding back the desert."

https://www.cifor.org/library/6980/

Look at zai pits. I think they do a lot of what you're discussing. Also, the pit idea is good for not only trapping rainfall and runoff, but also sediment and leaf drop, making more soil.

If you are concerned about aridity and desertification, I suggest you look at Air well (condenser)s. Those combined with drought-hardy trees that shelter the less-hardy will help combat its spread.

You seem to have a grasp on the type of arid-climate preparations you need. I think that, along the lines Ruth suggested, you might find other techniques that reverse the local spread of desertification, which will make the garden-scale adaptations you need less severe.

-CK

Chris Kott wrote:Look at zai pits. I think they do a lot of what you're discussing. Also, the pit idea is good for not only trapping rainfall and runoff, but also sediment and leaf drop, making more soil.

If you are concerned about aridity and desertification, I suggest you look at Air Wells. Those combined with drought-hardy trees that shelter the less-hardy will help combat its spread.

You seem to have a grasp on the type of arid-climate preparations you need. I think that, along the lines Ruth suggested, you might find other techniques that reverse the local spread of desertification, which will make the garden-scale adaptations you need less severe.

-CK

Chris, your link doesn't take you to a valid article.

I've had great success with pits with rotten wood and other organic material.  I'm growing a good crop of corn this way with very low water.  My entire Kitchen Garden has buried wood and it holds moisture much better than unimproved ground, though it still needs some irrigation for normal vegetables.

https://permies.com/t/52077/Buried-Wood-Beds

They use mulch pits at the Greening the Desert site in Jordan


Personally for your scheme I would make big pits like they do in Jordan, and put trees you plan to keep rather small around the outside spaced maybe six feet apart or so, depending on how small you plan to keep them.  It looks like for larger growing trees they put one on either side of a pit.  I'm thinking four trees per large pit might be good.

This video answers the question about using mulch pits for big trees. Geoff lawton shows an example of a long trench pit instead of a round pit. Trees that keep a small radius (like bananas) are used with the pit. Larger trees that branch out use the trench.

Watch "How to Scale Up Mulch Pits" on YouTube

Trace Oswald wrote:

Chris Kott wrote:Look at zai pits. I think they do a lot of what you're discussing. Also, the pit idea is good for not only trapping rainfall and runoff, but also sediment and leaf drop, making more soil.

If you are concerned about aridity and desertification, I suggest you look at Air well (condenser)s. Those combined with drought-hardy trees that shelter the less-hardy will help combat its spread.

You seem to have a grasp on the type of arid-climate preparations you need. I think that, along the lines Ruth suggested, you might find other techniques that reverse the local spread of desertification, which will make the garden-scale adaptations you need less severe.

-CK

Chris, your link doesn't take you to a valid article.

Fixed the original link. Thanks for the heads-up.

-CK