Zai pits, or “tassa’s” are holes that are dug in non-permeable ground about 5-15cm deep, and a diameter of 15-50cm, these pits are usually dug 80cm from each other. There is poorly available, organic matter which is placed at the base of the pit to create in a sense a wall, this organic matter attracts termites who then digest the organic matter and make nutrients more available, and dig tiny tunnels back and forth which improves the architecture The point of these pits is to collect run off. Zai pits are not widely used, they are a style of planting in Mali, Burkina Faso, and Niger provinces. When the weather turns bad and the holes get too much water in them debris will also begin to add up. You have to make sure that the debris is evenly placed. Extra debris in the Zai pits will soak up the water and the plant in the pit will not retain as much as it needs. Zai pits are completely free, that is if you do not enter the aspect of workers to dig them and the tools you will need to dig them, first you will need 20 people to work for you for 30-70 days depending on how big the land is. The only disadvantage in building these Zai pits is that you have to look over them, because if one gets “clogged” or full of debris it will die. If you continually clean out your Zai pits then you will be able to reuse them for years and years on, another way to keep them fresh and strong is to put a 2 or 3 inch lip around the top edge of the Zai pit, this helps the run off water get collected, and also keeps the Zai pit area looking neat. This technique is not a technique that we should be considering for our DOT garden, only because we do not get a lot of rain, in fact we only get on average 7in a year. And that is not enough to build a Zai pit, we are better off just watering our plants by hand. Although Zai pits are supposed to be used in dry places, because the soil is non-permeable and this is a better way of having the plant get to the water, I was thinking that maybe instead we could build out own Zai pits and then plants our crops in them and instead of waiting for a drop or two of rain we could fill our Zai Plants up by ourselves, still using the organic matter at the base.
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