Sturdy, carefully placed rock structures have withstood extreme flood events and continue to increase moisture levels for flora and fauna.
Written by: Trevor Hare and David Seibert
Using sediment transport as a surrogate for e.coli presence and transport across degraded landscapes, this project has surveyed, planned and mitigated severely eroding rangelands on the Sands Ranch west of the San Pedro River. Hundreds of rock erosion control structures were installed strategically to arrest sediment and e.coli movement toward the river, while an experimental ripping-on-contour method approved by ADEQ was employed to improve habitat conditions for native grasses to establish and continue the restorative process. Based on site visits and communication with ADEQ officials and ranch manager Ian Tomlinson, priority areas for erosion mitigation work include 1) extensive areas east of Hwy 90 previously sprayed with herbicide that have not recovered vegetatively; and 2) an area west of Hwy 90 that will benefit from the arrested movement of e.coli into the riparian corridor.
This site also serves as a public demonstration and youth education work site due to ease of access and high project visibility. Here the site will function as a training ground for use in our highly successful Borderlands Earth Care Youth program, a community-based effort that includes Patagonia High School's new Ag Science Program students, with new programs now in Douglas and Nogales. As part of a larger effort to expand to schools in Sierra Vista and beyond, this effort also takes advantage of an existing Borderlands grant with AZ State Forestry and the University of Arizona Cooperative Extension's Water Wise program, in order to utilize the sites as platforms for ongoing environmental education. Beneficial effects also include increased moisture levels and native seed banking effects afforded by structure installation in small and mid-sized rills and arroyos. The combined effects of the work will secure and nudge the uplands into a more resilient ecological condition, wherein native plants can gain a foothold and continue to hold soils and e.coli in place, while increasing native plant density and diversity and modeling efficient restoration practices.
On September 29th & November 10th @ 9 – 11 am
Trevor Hare will host a tour of an erosion control site with rock work, gully plug and pond work, and on-contour ripping.
This unique project funded by the AZ Dept of Environmental Quality brought a couple of newer techniques to the area to deal with erosion. Plug and Ponding of unstable gullies and on-contour ripping of areas with intensive and extensive sheet erosion.
Location: On the east side of Hwy 90, 12.5 miles south of I-10 and 6 miles north of Hwy 82 at the Dry Canyon Access Road
For any questions please contact: Trevor Hare at firstname.lastname@example.org
Ripping the most degraded areas on contour speeds up moisture infiltration and creates a viable bed for fall 2018 seeding of native grasses.