LOCAL APPLICATION OF THE TECHNIQUE CULTIVATION OF LIVING FENCES 44

LOCAL APPLICATION OF THE TECHNIQUE

Technique: CULTIVATION OF LIVING FENCES Local name: LIVING FENCEROWS IN SONORA FOR FLOODPLAIN MANAGEMENT AND SILT CAPTURE Site: Rio San Miguel, Sonora, Mexico, North America Location Click the globe to see the techinique on Google Map Continent: North America Country: Mexico Site: Rio San Miguel, Sonora Coordinates: Lat: 30.292455 Long: -110.712987 Description of the local variant of the technique In Sonora, living fence-rows are used for floodplain management along agricultural fields. They are referred to locally as "woven fences" (cercos de tejido) or "branch fences" (cercos de rama). Living fence-rows of willow (Salix gooddingii) and cottonwood (Populas fremontii) are planted between the Rio San Miguel and floodplain agricultural fields along the river. To plant the fence-rows, tall cuttings are made from mature, previously propogated fence-row trees, and a deep trench is dug down so that the water table is reached. The cuttings are planted fairly close to each other at even intervals (0.5 - 0.75 m), with the base planted firmly below the water level. Sand and gravel is then shoveled around the plantings. Generally, more willows are planted than cottonwoods. As the trees root and mature, brush is collected and woven between the trunks. Plants used for brush include Seep willow (Baccharis glutinosa), burrobush (Hymenoclea monogyra), mesquite (Prosopis iuliflora), and groundsel (Senecio salignus). During flood events, the soil is stabilized by the roots of the planted fence. Floodwater is still able to permeate the woven brush, but with reduced intensity, allowing the floodwater to irrigate the agricultural fields in a controlled manner. The water is slowed enough to cause a deposit of carried sediments. This process not only fertilizes the agricultural fields with nutrient-bearing silt, it actually grows the fields over time, as most sediment is deposited directly on the other side of the fence. There are many recorded instances of new fence-rows being planted as the fields expand to meet the first fence. Survival prospects Erosion of agricultural land is a pervasive and debilitating issue for cultures throughout history. Using living fence-rows in floodplain agricultural fields, valuable agricultural land is not only protected from erosion, but is actually improved in size and quality. The proliferation of selected willow and cottonwood trees further created excess lumber resources for fuel or construction. The trees also house insectivorous bird populations which help to control pests in the fields. This provides a productive and sustainable solution to riverbank erosion that would endanger the river as well as the agricultural land around it. Survival prospects are improved by sustained river health and protection and fertilization of agricultural fields Images Deepening TRADITIONAL TECHNIQUE DATA Technique CULTIVATION OF LIVING FENCES Icon Cathegory B - Agriculture Identification code B14 Other Local applications of the technique RELATED TECHNIQUES B9e SOIL CREATION AND REPLENISHMENT B10c IRRIGATION BY FLOOD RECESSION D5 PLANT SPECIES TO COMBAT EROSION Author: Tynan Hartzell Other authors: Reference: http://www.jstor.org/stable/4602400Living Fencerows of the Rio San Miguel Sonora Mexico: Traditional Technology for Floodplain Management Gary Paul Nabhan and Thomas Edward Sheridan Human Ecology Vol. 5 No. 2 (Jun. 1977) pp. 97-111 Published by: Springer pp. 97-111 Published by: Springer