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Dolores River Restoration 4.0 - Utah
Region: Southeastern
ID: 5215

Project Status: Completed

Completion Form

2021

This project utilized a broad toolkit of methods to restore riparian areas along the Dolores River in Utah. Typical methods include the cut-stump method for initial tamarisk removal, a basal bark and/or foliar spray for tamarisk re-sprout work to maintain legacy treatments, spot spraying for knapweed, and vegetation monitoring. Restoration is rarely immediately recognized, and therefore the ability to implement monitoring and maintenance is a critical component to the success of this project. Site-specific treatment methods are as follows:

ROBERT'S BOTTOM AREA

"Above Robert's Bottom" (River Left):

Canyon County Youth Corps (CCYC) spent three weeks, conducting primary tamarisk treatments totaling 3.9 acres and resprout treatments on 2.3 acres within the 18-acre site just upstream of Robert's Bottom on river left. Crews used chainsaws and loppers to cut tamarisk and immediately applied Tahoe 3A (Triclopyr) diluted with water to the stump. Beetle-kill tamarisk was hand removed and slash was piled away from cottonwood driplines.
Native grass seed was also broadcast at these sites where tamarisk removal has occurred by a contractor in March 2021 in order to help suppress weeds, increase the seed bank of native grasses, and improve the overall area.

"Lake Bottom BLM Lentic Site":

CCYC spent two weeks treating initial tamarisk and tamarisk re-sprouts on BLM lands at Lake Bottom in the fall of 2020. 1.5 acres were treated during this time. Crews used chainsaws and loppers to cut tamarisk and immediately applied Tahoe 3A (Triclopyr) diluted with water to the stump. The same mixture was also applied to the stems of young tamarisk re-growth using the basal bark method.

"Robert's Bottom and Above Robert's Bottom Prescribed Grazing":

The Grand County Weed Department treated 0.1 acre of emerging Russian knapweed within Robert's Bottom using Milestone.

Prescribed grazing was not implemented nor was the funding utilized for the grazing or seed.  Line-Point Intercept (LPI) and cottonwood density data were collected during the previous iteration of this project, Dolores 3.0.  These data, in conjunction with a literature review and conversations with experts, were used to assess the current vegetative conditions and the potential to utilize prescribed grazing to shift the riparian understory community to a site dominated by native vegetation.  A grazing solution in this location needs to be able to address the kochia infestation within the more xeric river terrace composed of native upland shrubs and lacking cottonwood overstory, and within the more riparian cottonwood gallery characterized by a facultative-wet and obligate native shrubs and a cheatgrass understory, and finally, the knapweed infestation occurring under the cottonwood gallery upstream of Robert's bottom.

Goat grazing was not a feasible option because the target species (i.e. kochia, cheatgrass, and knapweed) are herbaceous and goats prefer woody species.  Native woody species (i.e. cottonwood, willow, sumac, privet, greasewood, rabbitbrush, rose, etc) are prevalent on the site and it would be challenging to target herbaceous weeds and avoid the risk to priority native species.  Goats would have to be contained and would require extensive effort to move containment infrastructure around the project site.  Sheep were not a great option due to proximity to native big-horn sheep populations and their potential as a disease vector.  Grazing would have to occur 2+ times a year increasing the logistical challenges.

STATELINE AREA

"Across from Berm":

CCYC spent three weeks conducting 2.0 acres of primary tamarisk treatments on river-right across from the berm site in dense stands in the fall of 2020.  Crews used chainsaws to cut tamarisk and immediately applied Tahoe 3A (Triclopyr) diluted with water to the stump. Slash was piled outside of the cottonwood dripline. An additional, 0.6 acres of resprouts were treated with a mixture of Garlon 4 ultra and oil using a basal and/or foliar spray technique.
When the raft trip was cancelled in the spring of 2021 due to low water conditions, the funds were carried over, and after avian clearance survyes, were ultimately directed towards another two weeks of corps work and another 1.1 acres was completed.

"Berm Site":

The DRRP Strike Team conducted isolated mature Russian olive removal on 1.3 acres and 4.6 acres of Russian knapweed treatment at the berm site on river left in the spring of 2021.  An additional 16 acres of resprout treatments from spring of 2019, not previously reported, are being reported here.  Resprouts were treated with a mixture of Garlon 4 ultra and oil using a basal and/or foliar spray technique.

"Colorado State-Line to Berm Site"

The DRRP Strike Team conducted isolated 23.4 acres of woody invasive resprout work, 6 acres of tamarisk removal on a mid-channel island, and 27 acres of Russian knapweed treatment with aminopyralid in areas between the Colorado stateline and the berm site in the spring of 2021.  Crews used chainsaws to cut tamarisk and immediately applied Tahoe 3A (Triclopyr) diluted with water to the stump. Slash was piled outside of the cottonwood dripline. An additional, 0.6 acres of resprouts were treated with a mixture of Garlon 4 ultra and oil using a basal and/or foliar spray technique.  Knapweed was treated with Transline.

"Beaver Creek Area"

The DRRP Strike Team conducted isolated 55.3 acres of woody invasive resprout work in the Beaver Creek area in the spring of 2021.  Resprouts were treated with a mixture of Garlon 4 ultra and oil using a basal and/or foliar spray technique.

MONITORING:

"DRRP Rapid Monitoring - Vehicle-based" (see attached report):

Rapid vegetation monitoring conducted by the SCC Strike Team occurred in Summer of 2020 and 2021 in the Moab Field Office on over 20 sites where restoration activities have occurred. Some sites that have not been treated were also monitored to assess future needs. This team uses tablets enabled with Collector for ArcGIS to collect spatial data. Moab sites will be monitored by the DRRP Rapid Monitoring team again in 2024. The new rapid monitoring report is forthcoming (matching funding from the DRRP and Walton Family Foundation) and will be posted to the WRI website when available.

Rapid monitoring is made up of four components: monitoring, passive recruitment, invasive species survey, and photo points. The monitoring protocol is where cover classes for different vegetation types (% tamarisk, % native cover, % total vegetation cover) are collected. Cover classes are generally in increments of 10% (i.e. 11-20%, 51-60%, etc.) and determined through ocular estimate by the strike team.

"DRRP Rapid Monitoring -- Raft-based":

The raft monitoring that occurred in June 2020 (under Dolores 3.0) using the DRRP rapid monitoring protocol on 2 sites that had initial tamarisk removal occur in the spring of 2019 between Fisher Creek and Granite Creek was used in planning the raft-based restoration trip that was ultimately cancelled due to low flows.  See the attached report.

"Robert's Bottom Line-Point Intercept Data Collection (see attached report)":
These data were used to assess the use of prescribed grazing for restoration in the Robert's Bottom area.  See grazing section above.

This project aims to increase the riparian and aquatic habitat value along the Dolores River in Utah. As part of a broad multi-state effort to reduce the amount of tamarisk and increase the overall resilience of the riparian area. Work occurred on prioritized sites along the Dolores River, between the State-line site (river-mile 149) and Robert's Bottom (river-mile 170), in Grand County, Utah. Sites have been prioritized based on Dolores River Restoration Partnerships' ecological, social, feasibility criteria, and locations of side-channel/confluence habitat. Sites in the project area vary between levels of restoration, from fully restored and naturally recruiting. For more specifics on locations of specific restoration treatments, please refer to the accompanying map and/or the project details page.

The project was completed through collaboration between the BLM Canyon Country District Aquatic Habitats program, the Dolores River Restoration Partnership (DRRP), RiversEdgeWest (REW), the BLM Canyon Country Fuels program,  the Canyon Country Youth Corps (CCYC), Southwest Conservation Corps (SCC), the Grand County Weed Department, Rio Mesa Center, Western Biology LLC, Terra Sophia, LLC and UDWR/WRI.  The project focused on treating Russian olive, tamarisk, Russian knapweed, and Kochia and completed 68.3 acres accessed by vehicle. The BLM Canyon Country District Aquatic Ecologist and DRRP coordinators from SCC and REW provided project planning and field support for all project areas. The collaboration made significant progress towards causing mortality of woody and herbaceous weedy species and increased resilience of native species within important side channels, confluence, and riparian habitat.

ROBERT'S BOTTOM AREA
 
"Above Robert's Bottom":

Conservation Corps crews and the BLM have been treating woody invasive removal underneath a large cottonwood gallery on river left just upstream of from Robert's Bottom.  This cottonwood gallery, in combination with Robert's and Lake Bottom, create a cottonwood gallery complex, which is considered critical habitat for Yellow-Billed Cuckoo and may be important for SWFL. This is a large polygon and there is a lot of work left to do to remove ladder fuels and mitigate the risk of stand replacement fire here.  Native shrubs persist in the understory and are expected to improve in vigor and distribution following the removal of tamarisk.  Thus, work will continue to focus on removing tamarisk from underneath the cottonwood dripline and around native understory shrubs, while creating a safe fuel buffer around the stand.

Native grass seed was also broadcast by, Terra Sophia, at these sites where tamarisk removal has occurred.

"Lake Bottom":

CCYC also completed more removal near the lentic marsh/pond at Lake Bottom building off previous years' work. CCYC crews used a cut-stump-herbicide method (Tahoe 3a) to treat mature tamarisk and a foliar/basal bark application (Garlon 4 Ultra/Oil) to treat woody resprouts. This lentic site is dry in drought years but provides important lentic habitat for birds and amphibians during normal/wet years.  By removing invasive species, we hope to reduce encroachment and maintain the site in perpetuity.

"Robert's Bottom and Above Robert's Bottom Prescribed Grazing":

The use of prescribed grazing as a tool to manage weedy herbaceous species was evaluated.  Vegetation cover and composition data collected by the GCWD under Dolores 3.0 and summarized by the BLM Aquatic Habitats Intern was used in discussions with grazing specialists and colleagues.  A literature review was also conducted.  While prescribed grazing is a useful and successful tool it proved to be to challenging given the complexity and ecological goals at this site.  The ability to employ prescribed grazing with goats or sheep, outside of a few small areas, is not feasible due to presence of natural big-horn sheep populations and management plan policy.

The use of mowers or string-trimmers is being evaluated as an alternative to prescribed grazing.  These techniques may provide the more targeted approach necessary.

STATELINE AREA

"Across from Berm":

CCYC Crews continued working on the initial removal of tamarisk and Russian olive and treating resprouts from previous work, on river-right across from the historic berm site.  A large mature cottonwood gallery dominates the overstory of this site. This cottonwood gallery, in combination with the cottonwoods at the berm site, create a cottonwood gallery complex, which is considered critical habitat for Yellow-Billed Cuckoo and may be important for SWFL. The understory is dominated by beetle-impacted tamarisk with a moderate number of native shrubs intermixed. 
 
The majority of the initial removal of woody invasives is complete with the final removal efforts likely wrapping up under Dolores 5.0 (funding permitting).  Much of this area is part of a historical grazing allotment and has large infestations of knapweed.  Once the initial removal is complete future work will address resprouts (as needed) and focus on knapweed abatement and herbaceous restoration.

"Berm Site":

As mentioned in previous reports, in February of 2019, the Moab BLM removed a portion of the historic berm, which opened up the historical flow path allowing the river to flow into the floodplain for the first time in decades. In 2019 with sustained high flows, the site was inundated for several months.

In order to maintain an unimpeded flow path in the reconnected side channel, a DRRP strike team treated isolated mature Russian olive and woody invasive resprouts within the berm site in the spring of 2021.  The side channel did not inundate during this phase of the project.

MONITORING

DRRP Rapid Monitoring - Vehicle-based (see attached report):  
The rapid monitoring report that includes the 20 sites visited under this project will be available in the fall of 2021 and will be uploaded to the WRI website at that time.

Avian Surveys
Avian surveys were conducted by a contractor so that restoration work could be completed at the Across from Berm site during the summer of 2021 using the funds from the cancelled raft trips.

CHALLENGES

Raft-based restoration trip - Low late-season snowpack and warm temperatures again resulted in drought conditions and low river flows from the Dolores River and San Miguel River. Therefore, not enough water was flowing to get rafts to carry crews and their equipment down for treatments for the second consecutive year.  These raft funds were re-prioritized to achieving more land-based initial tamarisk removal at the "Across from Berm" site. If 2022 conditions are better, project managers would like to conduct treatments in the remote raft-accessible section between Fisher Creek and Rio Mesa based off information for the raft monitoring trip.

Grow-out of native species naturally occurring at Robert's Bottom -- This project occurred again during a severe drought.  The target native forb and grass species for collection did not produce enough seed for collection.  I decided it was better to leave what little seed there was on site.

Many sites along the Dolores River will continue to require maintenance of past work, specifically, the re-treatments of tamarisk and Russian knapweed. Furthermore, monitoring and maintenance is critical to ensure Russian olive or Siberian elm does not begin to overwhelm the river system. Additional restoration work at sites that have had initial tamarisk removal and secondary weed treatments also include broadcasting native seed and planting container plants where additional canopy structure is needed.  Dolores 5.0 will build off past efforts and work largely within the same areas.

ROBERT'S BOTTOM AREA

"Robert's Bottom"

The initial removal of tamarisk was completed many years ago.  However, full understory restoration of the site has not been achieved.  To integrate more tools into the Integrated Pest Management (IPM) toolbox for addressing herbaceous weeds, the 4.0 proposal intended to utilize prescribed grazing with goats to address Kochia and knapweed infestations at Robert's Bottom and at the cottonwood gallery just upstream (100 acres).  As mentioned above, prescribed grazing was analyzed and ultimately not employed.  The use of mowers and/or string trimmers to remove flowers before the plants go to seed may be utilized in combination with seeding and herbicide in Dolores 5.0.

"Above Robert's Bottom":

Youth corps saw crews will continue to be needed to remove the initial tamarisk underneath the cottonwood gallery upstream Robert's Bottom in subsequent years. Work will continue to move upstream and cut tamarisk around native trees and shrubs using a cut-stump approach while also treating resprouts from legacy treatments.  There is a lot of initial removal that needs to take place here.  The use of mowers and/or string trimmers to remove flowers before the plants go to seed may be utilized in combination with seeding and herbicide in Dolores 5.0.

STATELINE AREA

"Across from Berm":

This site was treated in Fall 2020 and Spring 2021. This site is close to having initial TRO removal complete. Project managers hope to complete work in 2022, with necessary follow-up (re-sprout and secondary weed treatments) for at least three years. Work will treat resprouts from legacy treatments and continue to employ a cut-stump approach to remove tamarisk from underneath the cottonwood gallery and from around native shrubs.  The side channel, perennial pool, and mid channel island will be assessed for resprouts.  Monitoring vegetation composition changes, treating secondary weeds, particularly Russian knapweed will be the focus as we finish up initial removal.

Working with the grazing permittee to implement prescribed grazing of knapweed should be explored.  These cows were seen eating knapweed within the permitted pasture.  Particularly summer grazing followed by late fall herbicide application targeting knapweed.  Seeding prior to grazing may also be beneficial.

"Berm Site":

The berm site is a priority area within this project given the connectivity to a side channel and shallow groundwater. Russian olive have began to grow here, a rare occurrence on the Dolores River. It is a priority of the DRRP to eliminate seedlings as soon as resources allow. The site was treated by the DRRP strike team in March 2020 and 2021, and monitored by the DRRP Monitoring Team in June 2021.

RAFT ACCESSIBLE AREA

More initial removal and resprout work needs to be completed in this reach.  A raft-based restoration trip is planned for each phase if flows are sufficient.

DRRP Monitoring:

Monitoring will continue on every site once every three years using the DRRP Rapid Monitoring protocol. See the 2019 monitoring report in the images/documents section. A report for the 20 sites monitored under Dolores 4.0 will be uploaded this fall (2021) when complete.  The next year will be 2024. Raft sites will be monitored when there is enough water to access the sites.

This project will require additional years of follow-up treatments and initial treatments on tamarisk and Russian olive (TRO.) Most sites will just require re-treatments as needed (Granite Creek, Lake Bottom, and Stateline,) and some sites will require 1-3 years of initial removal (Upstream Robert's Bottom, Berm Site., and Raft Sites.) The raft-based sites in particular will require additional work, which has been challenging because of low flows the past two years.

Continued monitoring will also help inform the status of re-treatment needs, which may include TRO resprouts, secondary weeds, or active revegetation.

Gabriel Bissonette

08/24/2021 17:10:48