Do You Diguette?

I went to the Negev yesterday with a few colleagues and I got into a discussion with Shany about the JNF (Jewish National Fund) plantings we saw.  I contended that the technique for planting the rows of trees was called “Liman”; she called them “Terrasot” (pl. for terraces in Hebrew).  Shany said that “Liman” is a term only used for planting trees in bowls – depressions in the ground made to preserve water in the center of the bowl.  According to her, these lines of piled up soil on the sides of the hills were terraces, similar to the terraces we see throughout the central mountain range.

Up until this point, I thought I understood Negev agricultural terminology; and, I was so convinced that I was right, I decided to do a bit of research to find out if both the desert farming technique using “bowls” and the technique of building up lines of soil on hillsides were both called “Limans” or if one was a Liman and the other a simple terrace.

This research took me into another question I have been wanting to tackle which was posed by Leah from my Tour Guide class.  She asked what was the name and the purpose of the rock piles we see all over the Negev.

I like to remind people who are traveling with me that despite appearances, Israel has plenty of natural resources.  We have water, sun, access to other places, trees, land – and all this was sufficient for supporting rich societies here ONLY because people knew how to manage them.  Ecology may be a 21st century idea for the rest of the world, but here in Israel ecology has been a necessity since the dawn of civilization.

So, too, in the Negev, an area which received less that 200 mm rainfall a year (in some places much less).  In antiquity, the people living in this desert climate figured out how to harvest water during the bleak winter rains, channel it to fields and grow wheat, barley, wine, olives, figs, etc.  It may take a lot of engineering and a lot of land, but it is possible.  Around the area of Avdat, approximately 25 acres of land were needed to collect enough water for 1 acre of crops.

One technique used by ancient peoples was the Liman.  A Liman is a depressed area surrounded by low hillocks.  The water falling on these hillocks flows into the center of the “bowl”.  This technique was initially used by the JNF  for planting large trees to provide shade.  You can see many JNF Limans on the road down to Beer Sheva. Most of the Limans planted in the Negev today are populated by Eucalyptus trees as they grow quickly.

Another technique is the Diguette.  Diguettes are small mounds built along a line on a slope.  Trees can then be planted uphill from each of these lines.  The mounds help to catch the water flowing down the hill and give it a longer exposure to the plant, decreasing run-off.  In Hebrew they may be called “Terraces” but actually they have a special name/function when they are in a desert climate. Diguettes are used around the world in arid areas, including Africa, and boost the ability of an area to produce crops thereby saving lives today.  The JNF uses Diguettes today to plant indigenous species and it is the main technique used in the Yatir forest project.

Catchment farms were used in natural stream beds.  Various dams were built along the stream bed.  The rain which fell on the surrounding hills flowed naturally into the stream bed, where the crops were. The water which overflowed each step of this terraced structure flowed to the step below, controlling the amount of water in each step and holding the water in the farmed area for a longer amount of time.

The rock piles my friend Leah asked about are an interesting phenomena in the Negev.  They are called by the local population Tolilat al-Anev (Grape Mounds).  In the 1830’s when these were first described by 2 British surveyors/explorers/botanists/geologists, it was assumed that these mounds were used in ancient times for growing grapes.  On further inspection, not only were there no grapevine remnants found in any of the areas, but also there were no adjacent wine presses.  There still is no definitive explanation for these mounds, but there are a few theories.  One is that the  clearing of the rocks into mounds allowed for more erosion of the soil on the slopes.  This soil was washed to the
valleys and mixed along the way with organic material to make a richer soil in the valleys.

The mounds are not only found on the slopes of hills, but also in relatively flat areas.  This leads to another hypothesis that the rocks randomly strewn about impinged upon the rainwater’s path to a central point.  Gathering the rocks in mounds meant that there was more free and clear smooth ground to draw the water to that central collection area.

Turns out that I was only partially right about Limans.  Shany was correct that Liman is a very specific term and not a general one. Thanks to Shany and Leah for piquing my curiosity and pushing me to learn more about agriculture in the Negev!

Do you Diguette?  I DO!