The assembly of small rock walls coming to the foreground is a gabion system that Tanya and I designed and constructed using rocks from the site.
Without the gabions, water would likely rush down hill causing erosion and damage to the surrounding area. With the gabions in place water is slowed and soaked into the soil giving us an opportunity to assemble a productive ecosystem of useful plants.
Gabions first slow the water down and secondly collect sediment and other materials behind them. The top edge of the gabion is roughly level from end to end, pacifiying the flow of water down hill. As material builds up behind the gabion, a level area of moist soil is built up. This becomes an excellent area for growing plants.
Gabions are a desing feature often used in deserts, fequently measureing meters in height. In this case a smaller scaled down version is most appropriate.
A swale is an on contour water harvesting foresty system. Swales intercept and hold water running down slope. Once in a swale water has an opportunity to soak into the soil and move into the root zones of the plants in the swale mound and in pastures below.
The laser level is a great tool, as it requires only one person to use efficiently. However, the laser level is battery operated and cannot be looked through like a dumpy (transit) level.
For now we have seeded this swale heavily with 5 different legume seeds: clover, lucerne (alf alfa), vetch, peas, and lupin. We made sure that all seeds were innoculated with the appropriate nitrogen fixing bacteria and then they were well raked in. Its an experiment! In about a months time we will begin to plant trees into the swale mound. We do not have the trees, or we would have planted now.
water moving through gabion system towards the swale
Originally uploaded by tlbaraka