The name of “gully plugging with stem cuttings”, refers to an intervention that rehabilitates gullies by building check dams made of tree stem cuttings, to control erosion and runoff. These living barriers are pretty efficient in slowing down runoff water and stopping the sediment that gradually fills up the gullies. Field research has proven that they work well in soils of sandy/loamy texture, where the performances of these check dams, made of tree stem cuttings, are greater than the ones of stone dams, due to rooted poles and the root system of the living barrier.
For this type of intervention, the most suitable material is stems with a diameter of 5-15 cm and 1.5-2.5 m long, depending on the depth of the gully. The cuttings are planted for half of their length and placed to form a semi-circular barrier. Dams are spaced according to the slope of the gully bed. Dams aim to reduce runoff speed and stop the eroded sediment. This way, the portions of the gully between the dams will fill up with eroded soil. In addition, over time the agricultural land that was divided by the gully, will become reconnected, allowing the runoff to be further reduced.
In order to obtain the best results, it is recommended to integrate this intervention with other Soil and Water Conservation measures on lateral slopes, such as retention trenches or live barriers along the contour. Moreover, in order to improve the effectiveness of the stem cutting barriers on moderate slopes, it is recommended to combine them with stone dams.
In addition, to maintain the efficiency of stem cuttings barriers over time, it is crucial to provide for their maintenance. This includes pruning of the stems, (which will lead to the production of wood and fodder), replacing dead poles and widening the barriers width, if necessary.
Image source: Food and Agriculture Organization of the United Nations, 1986, M. P. Geyik, FAO watershed management field manual, http://www.fao.org/3/ad082e/AD082e00.htm#cont. Reproduced with permission.