At 7am, in the relative coolness of Saturday morning, July 15, Borderlands Restoration Network (BRN) held a restoration awareness event as a walk among six of its projects in the Borderlands Wildlife Reserve along SR 82 north of Patagonia. Zach Farley, Watershed Restoration Crew Leader, led a group of ten on a walk among the sites, and used the rock structures to share permaculture principles for containing erosion and slowing waterflow in washes. At each site, Zach encouraged awareness of what water was doing there, where it had come from and where it was headed.
Along our walk, we learned about three types of rock placement restoration projects, the first, a one-rock dam. The dam consists of a line of rocks across a wash one or two deep that captures sediment, eventually filling to create a ‘slow zone’ where water can settle back into the ground. A second form often used is ‘media luna,’ the half-moon shaped curved rock placements that slow water above a head-cut or other erosion locations. The third common form of rock placement is the ‘zuni bowl,’ a curving vessel for stabilizing an eroding bank. They’re often used where erosion is cutting at the roots of trees. Zach explained that the rocks are placed in dirt or sand that’s been softened, always dry, i.e. without mortar. Unlike some more casual placements for stone rip-rap, BRN’s style of rock fitting could be described as careful without being neurotic about perfection.
At each site Zach showed the plants that were taking hold among the rocks, some transplanted, some as the result of the placement of seed balls or seed pancakes. A mixture of native seeds, sand and clay, the seed balls are prepared by BRN’s Nursery under Francesca Claverie. The starting plants from seed balls are in competition with the existing plants nearby that can self-seed, but also in competition with invasives like tumbleweed. However they get into the rock projects, plants are a vital part of the long-term wellbeing of the rockwork.
BRN’s Watershed Restoration Program Manager Tess Wagner added to Zach’s presentation, beginning with the point that their rock-dam and retention projects in Wildlife Corridors are not to combat the kind of erosion that’s natural around there, such as cuts into stream banks, but rather to remediate human-caused erosion. A main source of the erosion, she said, was runoff from roadways, and added that BRN was exploring runoff ditches, extended speed bumps, permeable pavements and other ways to prevent road runoff from building into a strong erosive current, or from moving a lot of soil. In answer to a question about the use of salvaged concrete rubble, aka “urbanite,” for these structures, she added despite the attractiveness (and price) of that material, concrete could alter the chemistry of soil and water and thus wasn’t a good material choice.
Zach, a musical instrument maker and player, played short improvisations on different instruments at each stop. He favors flutes and stringed instruments and creates percussion toys as well. He works with all kinds of natural materials, including agave and yucca stalks, mesquite, gourds, and deer antlers. The antler piece was a small flute, and the dipping gourd piece was a two-person instrument about four feet long, a wind instrument on the neck end and a kalimba on the other.
The experience was enjoyable with take away lessons of both the rock work and the instrument making: Work with what you’ve got.