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  • This manual is intended to assist both the experienced revegetation professional as well as a landowner new to revegetation. It was developed through a synthesis of the best current research combined with experience from actual project managers in the Upper Colorado River Basin. The organization and recommendations of this manual generally follow the 7-step process recommended for tamarisk projects (defining a goal, establish a realistic restoration objective, prioritize and select sites, create site-specific restoration plan, implement plan, conduct post-project monitoring, and engage adaptive management). 
    This manual can be purchased from Dr. Anna Sher, via her website.
  • This guide by Drs. Scott Nissen, Andrew Norton, Anna Sher, and Dan Bean offers key options and considerations for tamarisk treatment, including biocontrol, targeted guidance on how to develop management plans, implement various control strategies, and plan restoration for treated sites. Useful resource as an accompaniment to Sher et al. 2010. 
    Nissen et al. 2010.   
    Prepared by the RiversEdge West (formerly Tamarisk Coalition) in 2008, this document addresses options for the control, biomass reduction, and revegetation management components. All currently available technologies have been evaluated; however, not all are applicable for a given river location. Tamarisk is the focus of this document’s control component because it is the principle non-native phreatophyte in western watersheds. In general, the following discussion applies to Russian olive and other invasive trees but may differ slightly for each (e.g., herbicide used).
  • This 2008 report summarizes an inventory of tamarisk and Russian olive infestations on all the major rivers and their main tributaries in Colorado. The report  was completed by the Tamarisk Coalition for the Colorado Water Conservation Board. The purpose of this work was to 1) establish and implement an inventory protocol that would be economical to perform, 2) provide a relatively accurate understanding of the extent of the tamarisk problem in Colorado, 3) develop water and wildlife habitat impacts, and 4) estimate the cost of restoration.

  • This PowerPoint, prepared by Dr. Ken Lair, Chuck Bell, and Jackie Lindgren describes challenges related to tamarisk control and riparian restoration in the Mojave River Watershed.

  • This guide by Drs. Scott Nissen, Andrew Norton, Anna Sher, and Dan Bean offers targeted guidance on how to develop management plans, implement various control strategies, and plan restoration for treated sites. 

  • Vegetation response to invasive Tamarix control in southwestern U.S. rivers: a collaborative study including 416 sites

    Gonzalez et al. 2017

    Most studies assessing vegetation response following control of invasive Tamarix trees along southwestern U.S. rivers have been small in scale (e.g., river reach), or at a regional scale but with poor spatial-temporal replication, and most have not included testing the effects of a now widely used biological control. We monitored plant composition following Tamarix control along hydrologic, soil, and climatic gradients in 244 treated and 172 reference sites across six U.S. states. This represents the largest comprehensive assessment to date on the vegetation response to the four most common Tamarix control treatments. Biocontrol by a defoliating beetle (treatment 1) reduced the abundance of Tamarix  less than active removal by mechanically using hand and chain-saws (2), heavy machinery (3) or burning (4). Tamarix abundance also decreased with lower temperatures, higher precipitation, and follow-up treatments or Tamarix  resprouting. Native cover generally increased over time in active Tamarix removal sites, however, the increases observed were small and was not consistently increased by active revegetation. Overall, native cover was correlated to permanent stream flow, lower grazing pressure, lower soil salinity and temperatures, and higher precipitation. Species diversity also increased where Tamarix was removed. However, Tamarix treatments, especially those generating the highest disturbance (burning and heavy machinery), also often promoted secondary invasions of exotic forbs. The abundance of hydrophytic species was much lower in treated than in reference sites, suggesting that management of southwestern U.S. rivers has focused too much on weed control, overlooking restoration of fluvial processes that provide habitat for hydrophytic and floodplain vegetation. These results can help inform future management of Tamarix-infested rivers to restore hydrogeomorphic processes, increase native biodiversity and reduce abundance of noxious species.

    Key words: Diorhabda; exotic species control; management

  • Author(s): Steven W. Carothers; R. Roy Johnson; Deborah M. Finch; Kenneth J. Kingsley; Robert H. Hamre
    In the Preface to volume 1, we discuss the development of riparian ecology as one of the newest of ecological fields that gained significant momentum in the 1950s and 1960s as part of the general “riparian movement” in the United States. The field expanded rapidly throughout the latter half of the 1900s. Volume 2 involves more than two dozen authors - most with decades of experience - who expand upon riparian and other topics introduced in volume 1. Two important recent developments are global climate change and impacts of introduced tamarisk leaf beetles (Diorhabda spp.) in the American West. Other chapters in volume 2 that provide current information evaluate the losses of riparian habitat, including “extirpation” of a large number of mesquite bosques (woodlands) in the Southwest; the restoration of riparian ecosystems damaged by anthropogenic activities; the importance of a watershed; and the importance of riparian ecosystems to recreation. The combination of volumes 1 and 2 examines the evolving understanding of scientific implications and anthropogenic threats to those ecosystems from Euro-American settlement of the region to present. >> Volume 1 is also available in Treesearch:
  • AL Henry et al. 2021

    Abstract: Invasive species are a major cause of biodiversity loss worldwide, but their impact on communities and the mechanisms driving those impacts are varied and not well understood. This study employs functional diversity metrics and guilds—suites of species with similar traits—to assess the influence of an invasive tree (Tamarix spp.) on riparian plant communities in the southwestern United States. We asked: (1) What traits define riparian plant guilds in this system? (2) How do the abundances of guilds vary along gradients of Tamarix cover and abiotic conditions? (3) How does the functional diversity of the plant community respond to the gradients of Tamarix cover and abiotic conditions? We found nine distinct guilds primarily defined by reproductive strategy, as well as growth form, height, seed weight, specific leaf area, drought and anaerobic tolerance. Guild abundance varied along a covarying gradient of local and regional environmental factors and Tamarix cover. Guilds relying on sexual reproduction, in particular, those producing many light seeds over a long period of time were more strongly associated with drier sites and higher Tamarix cover. Tamarix itself appeared to facilitate more shade-tolerant species with higher specific leaf areas than would be expected in resource-poor environments. Additionally, we found a high degree of specialization (low functional diversity) in the wettest, most flood-prone, lowest Tamarix  cover sites as well as in the driest, most stable, highest Tamarix cover sites. These guilds can be used to anticipate plant community response to restoration efforts and in selecting appropriate species for revegetation.

    Author(s): R. Roy Johnson; Steven W. Carothers; Deborah M. Finch; Kenneth J. Kingsley; John T. Stanley
    Fifty years ago, riparian habitats were not recognized for their extensive and critical contributions to wildlife and the ecosystem function of watersheds. This changed as riparian values were identified and documented, and the science of riparian ecology developed steadily. Papers in this volume range from the more mesic northwestern United States to the arid Southwest and Mexico. More than two dozen authors - most with decades of experience - review the origins of riparian science in the western United States, document what is currently known about riparian ecosystems, and project future needs. Topics are widespread and include: interactions with fire, climate change, and declining water; impacts from exotic species; unintended consequences of biological control; the role of small mammals; watershed response to beavers; watershed and riparian changes; changes below large dams; water birds of the Colorado River Delta; and terrestrial vertebrates of mesquite bosques. Appendices and references chronicle the field’s literature, authors, "riparian pioneers," and conferences. >> Volume 2 is also available on Treesearch:

RiversEdge West's

mission is to advance the restoration of riparian lands through collaboration, education, and technical assistance.