Chapter 6 Riparian Authors: Corrine Dolan and Alix Rogstad

Cover photo: Courtesy of the “Living with Wildfire: Homeowners’ Firewise Guide for Arizona” tabloid published by The Arizona Interagency Coordinating Group.

Chapter 6 74 RIPARIAN

Description

people, and domestic animals. Riparian vegetation communities are valued for high biodiversity, including insect and crustaceous species that are vital in the food web. In addition, riparian areas are treasured for recreational activities such as hiking, camping, fishing, rafting, and bird watching. Furthermore, riparian areas provide environmental services that are important for ecosystem function, including improved water quality and quantity as well as erosion control.

Photo by Bill Boyett Riparian areas are dynamic and adapted to natural disturbances. Seasonal flooding is very important to Burro Creek the regeneration of the vegetation found in riparian Riparian (streamside) vegetation communities vary areas (Dwire and Kauffman 2003) because it reduces in structure and species composition, depending on or eliminates older, decadent vegetation and location. In general, riparian areas are transitional promotes newer, healthier plant establishment and zones between terrestrial and aquatic ecosystems. In growth. Floods serve to irrigate the surrounding other words, they are areas along a river or stream floodplain and wash away dead and dying litter with water-loving vegetation. Riparian vegetation and woody debris. Seasonal flooding also was communities can be found at all elevations and in important to Native American populations who each of the other vegetation communities described lived along the rivers of Arizona. Some tribes in this publication. To read more about riparian planted crops in the surrounding floodplain, using areas associated with other vegetation communities, the flooding events to irrigate and fertilize (Austin see the Special Case Boxes in Chapters 1 through and Wolf 2001). 3 of this publication. This chapter will focus on riparian areas at low elevations with flowing water at least part of the year. The riparian areas discussed in this chapter are different from neighboring vegetation formations because they are wetter, shadier, and contain different kinds of soils and plant species. Microclimates in riparian areas tend to be cooler with higher relative humidity when compared to adjacent vegetation communities (Dwire and Kauffman 2003). For the purposes of this discussion, riparian areas are considered to contain flowing water at least part of the year. There are approximately 93,000 linear miles (USGS 2004) of riparian vegetation communities (including streams, rivers, washes, canyons, wetlands) in Arizona (Figure 6.1). Box 6.1 describes types of riparian vegetation communities in Arizona and management concerns for each.

The presence of water, lush green plants, and cooler Photo by Cori Dolan temperatures attract a diversity of wildlife species, Fall colors in the Ramsey Canyon Nature Preserve

Chapter 6 75 Riparian

Figure 6.1 Riparian Areas in Arizona

Chapter 6 76 Box 6.1 Riparian Vegetation communities in Arizona* River Surrounding Location Fire Management Issues System Vegetation

Recreation is the biggest human use of this area. The steady rise in the number of visitors has increased human-caused ignitions. Ground-water Sonoran Desert Scrub, pumping by humans has drawn down the water table creating drier conditions West Central including a significant that are more conducive to fire. Finally, the surrounding vegetation includes

River Arizona nonnative species nonnative species such as red brome that increase fire frequency and size. component. Operations and releases from Alamo Dam are probably the biggest influence

Bill Williams on this river. Most of the river is on a National Wildlife Refuge, BLM- administered wilderness, and a few private ranches.

The Salt River extends through Forest, Woodland, Recreation has a large impact on the upper Gila, Gila Box Riparian Natural Southern and and Desert Scrub areas. Conservation Area (RNCA), and along the Gila River in the Winkelman area.

Rivers Western Arizona The Gila River is mostly There is a high potential for human-caused ignitions in these areas. surrounded by Desert Salt and Gila Scrub in Arizona.

This area is used for recreation by boaters and campers who increase ignitions along the river. A major cause of fires in this area is visitors setting fire to Russian thistle (tumbleweeds), a nonnative plant that carries and spreads fire Northwestern to other areas. To prevent nonnative plants from spreading, fire crews sanitize Mohave Desert Scrub River Arizona equipment before entering riparian areas. There is a buffer zone around the river where aerial retardant is prohibited to protect endangered fishes. Outside

Upper Colorado this buffer zone, fires are suppressed by firefighters with hand tools or are allowed to burn out.

A high priority in this area is the management of habitat for threatened and endangered species, many of which can be impacted by fire. In areas where salt cedar (Tamarix spp.) grows in large monotypic stands, fires exhibit extreme behavior that can threaten habitat and communities within the wildland-urban Western Arizona Sonoran Desert Scrub interface (WUI). Recreation is a significant activity on this river system and

River increases possible ignition sources. Undocumented immigrants also increase ignitions in this area. Some prescribed fire is used to manage threaten and Lower Colorado endangered species habitat. Most commonly, mechanical treatments such as thinning are used along WUI areas to reduce wildland fire risk.

Nonnative tamarisk (salt cedar) is not as much a problem along this river as Southeastern Grassland and Sonoran the others. Flood debris piles increase fuel loads within the cottonwood gallery Arizona Desert Scrub forest. Undocumented immigrants start fires along the San Pedro corridor.

San Pedro River

The biggest issue facing this system is the fact that the land bordering the river is private land. No agreement has been made among the landowners regarding a conservation plan for the area. The National Park Service is Southeastern Grassland and Sonoran constructing firebreaks near Tumacácori National Historical Park to reduce

River Arizona Desert Scrub fuel loads in areas that border human communities. The nearby wastewater

Santa Cruz treatment plant provides the stream flow to the Santa Cruz, increasing moisture content and decreasing the potential for a high-intensity fire. Therefore, fire management is a low priority in this area.

*Fire Management Information courtesy of the Bureau of Land Management and the National Park Service.

Chapter 6 77 The most common species associated with Box 6.2 Major Plant Species in Riparian lower elevation riparian communities are listed Communities in Arizona in Box 6.2 Detailed PLANT FACT SHEETS Arizona ash Fremont cottonwood with pictures of each species listed are located (Fraxinus velutina) (Populus fremontii) in Appendix C. Arizona sycamore Goodding’s willow (Platanus wrightii) (Salix gooddingii) Arizona walnut Mesquite The most common species associated with (Juglans major) (Prosopis spp.) lower elevation riparian communities are listed Cane bluestem Salt cedar in Box 6.2 Detailed PLANT FACT SHEETS (Bothriochloa barbinodis) (Tamarix spp.) with pictures of each species listed are located Deergrass Seep willow in Appendix C. (Mulenbergia rigens) (Baccharis glutinosa)

Box 6.3 Major Riparian Plant Species Associated with Other Communities in Arizona Pinyon-Juniper and Oak Mixed Conifer Forest Ponderosa Pine Forest Chaparral Woodland Bigtooth maple Arizona alder Arizona alder Arizona ash (Acer grandidentatum) (Alnus oblongifolia) (Alnus oblongifolia) (Fraxinus velutina) Boxelder Arizona ash Arizona sycamore Arizona sycamore (Acer negundo) (Fraxinus velutina) (Platanus wrightii) (Platanus wrightii) Narrowleaf cottonwood Arizona walnut Arizona walnut Arizona walnut (Populus angustifolia) (Juglans major) (Juglans major) (Juglans major) Quaking aspen Boxelder Fremont cottonwood Fremont cottonwood (Populus tremuloides) (Acer negundo) (Populus fremontii) (Populus fremontii)

Historic Fire Regime

Although there is little historical information Although fires are thought to have been historically regarding the role of wildland fire in riparian uncommon in riparian vegetation communities, vegetation communities, evidence suggests that fire there are accounts of fires spreading from adjacent was not a significant factor (Austin and Wolf 2001). communities (Davis 1982). There are also accounts First, the dominant tree species found in riparian of Native American tribes setting fires in riparian areas are not considered to be fire-adapted (USFWS areas to rejuvenate vegetation for the benefit of game 2002). Trees typically do not have thick, protective animals and birds (Williams 1994) and to clear areas bark nor do they regenerate quickly after being for planting (Austin and Wolf 2001). damaged by fire. In addition, the dominant plants in riparian areas do not require fire to germinate their seeds like the ponderosa pine trees discussed in Chapter 2. Riparian trees do, however, have seeds that respond to other environmental disturbances Although there is little historical - most commonly flooding (Dwire and Kauffman information regarding the role of fire 2003). in riparian ecosystems, evidence Second, plants in riparian vegetation communities suggests that fire was not a significant contain more moisture than plants in other vegetation communities found further from flowing rivers. factor. Flooding was the major natural Plants in riparian zones can maintain high water disturbance in riparian areas. content even in dry seasons, decreasing the risk of a fire carrying or igniting easily (USFWS 2002; Dwire and Kauffman 2003). Chapter 6 78 Current Fire Regime

increasing the area’s flammability (USFWS 2002). Flow regulation (i.e. dams) in rivers also decreases the amount of water in some riparian zones, leaving the area open to invasion by more drought-tolerant, flammable species such as salt cedar (Tamarix spp.) and red brome (Bromus rubens)(see Nonnative Plants section, this chapter). Salt cedar, or tamarisk, can spread intense fires quickly, killing native vegetation and opening the area up to further invasion by nonnative plants.

Photo by Bill Boyett Third, increased development in and adjacent to Fire on the Colorado River riparian zones contributes to the lowering of the water table. A decreased water table results in a drier There are three significant changes taking place and more flammable riparian area. An increase in the in riparian vegetation communities today. First, number of people drawing water from wells in the wildland fires, a once uncommon event, are wildland-urban interface is a significant obstacle to increasing in frequency and size due to increased the restoration of riparian vegetation communities ignition sources and a larger fuel load consisting of in Arizona. In addition, weather patterns play an more nonnative species. As the population of Arizona important role in the moisture content and fire increases (Appendix A), more and more people are frequency in riparian areas. During periods of living and recreating in riparian ecosystems resulting drought, high temperatures and decreased relative in more human-caused fires (Austin and Wolf 2001). humidity can contribute to the occurrence of fire Accidental ignitions from campfires, vehicle sparks, (Dwire and Kauffman 2003). and cigarettes as well as arson have increased potential ignition sources. Second, seasonal flooding, the most important disturbance factor in riparian zones, is decreasing in occurrence. Construction of dams in Arizona began in the 1930s (Austin and Wolf 2001) and had significant consequences for fire management. The resultant regulation of water flow has decreased large-scale flooding events that would carry small and large debris into the surrounding floodplain. Without floods to redistribute these fuels there has been a steady increase in the amount and continuity Photo by Brooke Gebow of litter and woody debris in riparian zones, thereby Rillito River, 1993 Fire Effects

Effects of fire on riparian vegetation communities depend on the intensity of the fire and the structure of the area. Some areas are slow to recover while others recover rather quickly (DeBano and Neary 1996). Fire can remove all or a significant portion of the plants along a stream. High-intensity fires in the surrounding vegetation can lead to excessive surface runoff into the water channel and a faster streamflow (DeBano and Neary 1996). Medium- to high-intensity fires can remove the litter layer, exposing mineral soil. While this process is beneficial to some plants, such as Photo by David Repass the ponderosa pine (see Chapter 2), it can be harmful Ash runoff in stream in riparian areas. When it rains after a fire, exposed

Chapter 6 79 soil can be washed into the stream channel. If too much sediment runs off into the stream, water quality is lowered and the stream’s ability to carry flood flows is decreased. In addition, a high-intensity fire can indirectly cause an increase in water temperature. If the fire removes a significant portion of the streamside vegetation, the water channel is exposed to more sunlight and water temperatures can increase significantly. Increased water temperatures result in lower dissolved oxygen levels in the water, which can create problems for aquatic biota (DeBano and Neary 1996).

Plants Photo courtesy of Bureau Land Management Fremont cottonwood Populus fremontii ( ) is a native, Prescribed fire on the San Pedro River to reduce mesquite deciduous, fast-growing tree that can be injured by even a low-intensity fire. Moderate-intensity fires will sycamore (Platanus wrightii), although they probably top-kill the tree, although it can resprout or recruit resprout after fire like other trees in those families from seed if seed is carried down from upstream (Reed 1993a). sources. Fremont cottonwood is not fire dependent, however, because it did not evolve with frequent fire Arizona walnut (Juglans major) is not adapted to (Taylor 2000). survive fire. Even mature plants are killed by fire, although seeds can survive if buried under soil (Pavek 1993). Mesquite (Prosopis spp.) trees can survive the passage of a fire by resprouting and producing abundant amounts of seeds. Fire mortality of mesquite is generally low (Steinberg 2001). If a tree is top-killed, numerous sprouts arise from underground buds that are protected from fire by soil and rough bark (Uchytil 1990). There is little information about the effects of fire on Goodding’s willow (Salix gooddingii) trees. Fire- damaged trees most likely resprout like other trees in this genus while wind-dispersed seeds probably are important in the colonization of recently burned sites (Reed 1993b). Flooding events are very important to the establishment of these trees. Nonnative salt cedar (tamarisk) has invaded many riparian areas in the southwestern United States. Salt

Photo by Matt Killeen, The Nature Conservancy Photo by Matt Killeen,

Fremont cottonwood (Populus fremontii) on the San Pedro River

Seep willow (Baccharis glutinosa) is not actually a willow, but a member of the sunflower family. It has resinous leaves that increase flammability and cause the tree to burn intensely, although resprouting can occur within a few weeks time (Mark Pater, pers. comm.).

There is little information regarding the fire effects Photo by Bill Boyett to Arizona ash (Fraxinus velutina) and Arizona Prescribed fire to remove salt cedar from a riparian area

Chapter 6 80 cedar resprouts vigorously after disturbances such as fire, often forming dense thickets that prevent native plants from growing (see Nonnatives Plants section, this chapter). Salt cedar is more flammable than native trees because it accumulates a large amount of dead, woody material within the plant (Zouhar 1993). Salt cedar-dominated communities accumulate fuels more rapidly than Fremont cottonwood-dominated communities due to the decrease in flooding. Consequently salt cedar-dominated communities burn about every 10 to 20 years (Zouhar 2003). Salt cedar also accumulates more fuels because it is low to the ground and traps debris carried by flood waters.

Native vegetation, including Fremont cottonwood, is Photo courtesy U.S. Fish and Wildlife Service often absent from these burned areas despite pre-fire Southwestern willow flycatcher Empidonax( traillii extimus) presence. Native vegetation usually is replaced by fire-adapted salt cedar. to habitat changes and therefore can be reduced in In systems with regular flooding (i.e. those not number after large fires (Rinne and Neary 1996). regulated by dams), native vegetation often Fire effects on wildlife are largely dependent on establishes and reduces salt cedar densities through the size and severity of the fire and the rate of plant crowding and shading (Sher et al. 2002). regrowth. The endangered Southwestern willow flycatcher Wildlife (Empidonax traillii extimus) uses salt cedar as breeding Riparian vegetation communities are important habitat (USFWS 2002; Shafroth et al. 2005), making because they provide critical habitat for numerous management of salt cedar-dominated areas more terrestrial and aquatic species (Naiman et al. complicated. In some cases, salt cedar provides 1993, Kauffman et al. 1997, Kauffman et al. 2001). flycatchers and other wildlife species habitat in areas Disturbance events such as wildland fire impact along rivers where no other tree species will grow due vegetation structure and water quality and therefore to increased depth to the water table. Some agencies, impact the aquatic animals that depend on riparian such as the Bureau of Land Management (BLM) are vegetation communities. Intense fires in riparian removing tamarisk along riparian areas with the areas can lower water quality by increasing water permission of the U.S. Fish and Wildlife Service with temperatures and the amount of sediment and ash in the goal of restoring the vegetation community to a the water. Aquatic animals are somewhat sensitive more natural structure. Human Dimensions

Humans have affected riparian vegetation probably more than any other type through diversions of the water that sustains these systems (Bahre 1991). For example, fire frequency has increased in the last few decades in this vegetation community because of human activities (Dwire and Kauffman 2003). The dramatic increase in the numbers of people living and recreating in riparian vegetation communities, as well as heavy undocumented immigrant traffic along the international border, increases the number of fire ignitions, through cigarettes, vehicle sparks, and escaped campfires. People are building homes closer to riparian areas that then become added fuel when a fire starts. In addition, the regulation of river flows by Photo courtesy of U.S. Fish and Wildlife Service dams increases the fuel load and locally decreases site Imperial National Wildlife Refuge water availability (see Current Fire Regime section,

Chapter 6 81 can severely alter the fire behavior of the habitat into which they are introduced, and are a major concern to land managers. Species such as Johnson grass (Sorghum halepense) and bermudagrass (Cynodon dactylon) are nonnatives that have become problems because of their ability to dominate and displace native species. (Mark Pater, pers. comm). The most significant and widespread nonnative species affecting low-elevation riparian vegetation communities today is salt cedar, also known as tamarisk. Salt cedar was introduced in Arizona in the early 1800s as an ornamental plant

Photo by Mary Teed Photo by Mary and was used beginning in the 1920s by the Bureau Cows graze in the San Pedro River of Reclamation for erosion control and as windbreaks along riparian areas. Dense stands of salt cedar have impacted river systems by crowding out native this chapter). Finally, increased populations living in plants, drying up water courses, and increasing the and near riparian zones are lowering the water table. occurrence of fires in riparian zones (Austin and Wolf The result is an increase in the number and intensity 2001) where the river has been regulated to prevent of fires and a reduction in the ability of riparian areas seasonal flooding. to serve as firebreaks (Dwire and Kauffman 2003). Salt cedar is able to invade because it has a longer Improper livestock grazing management can allow season of seed dispersal than native plants, creating nonnative species in riparian zones to increase by more opportunities for salt cedar to become considerably decreasing native species populations established. In addition, salt cedar gathers salt in and opening the area to invasion. Nonnative species its tissues and exudes it onto its leaves. These salts such as tamarisk (salt cedar) and red brome add accumulate in the soil surface layer when the plants a significant amount to the fuel load and lead to drop their leaves, resulting in increased soil salinity increased fire frequency and size. Improper livestock over time. High salinity prevents native plants from grazing management adjacent to riparian areas growing, especially in disturbed areas that are no can cause erosion (which can lead to increased longer subjected to annual flooding (Zouhar 2003). sedimentation within the riparian area), lead to channelization that accelerates runoff, and decrease the moisture available in riparian areas. Some agricultural practices can increase the amount of salt in riparian vegetation communities. Salts leached from soils by heavy irrigation can wash from agricultural fields into streams and the surrounding vegetation. In addition, irrigation leads to increased evaporation from the soil surface, which brings salts to the surface (Guy McPherson, pers. comm). Increased soil salinity favors nonnative plants such as tamarisk (salt cedar) over natives like willow because salt cedar is able to tolerate salty soils by accumulating salt in its tissues. In turn, nonnative salt cedar increases the fuel load in riparian systems.

Nonnative Plants Another alteration that humans make in vegetation communities is the purposeful or accidental introduction of nonnative species. A nonnative species is a plant or animal that moves into a place outside Apache-Sitgreaves National Forests Photo courtesy of of its natural geographic range. Nonnative species Salt cedar (Tamarix spp.)

Chapter 6 82 Fire Management Techniques

Photo courtesy of U.S. Fish and Wildlife Service

Photo courtesy of U.S. Fish and Wildlife Service

Prescribed burn at Imperial National Wildlife Refuge Scenic backwaters of Imperial National Wildlife Refuge

Fire has not been broadly used as a management that accounts for the flammable fuel load and by tool in riparian vegetation communities. Fire treat- increasing the moisture content of the surrounding ments are used periodically, however. For instance, vegetation. Second, in the long-term, flood pulsing the Bureau of Land Management (BLM) is conduct- allows native, flood-adapted species to thrive while ing prescribed burns along strategic areas of the San preventing highly flammable species like salt cedar Pedro Riparian Natural Conservation Area to reduce from invading the site. Flood pulses can be timed to hazardous fuel loads and retain the cottonwood struc- mimic natural flooding processes that aid in regenera- ture for critical bird habitat. To protect cottonwood tion and seedling establishment for trees like Fremont trees, managers pull litter and woody debris away cottonwood. from the trees as a pre-treatment for prescribed burn- Beaver (Castor canadensis) has been reintroduced on ing because cottonwoods are sensitive to heat. After the San Pedro River and the populations are being the debris has been pulled away from the trees, it is monitored. One result of the beaver reintroduction burned when weather conditions allow for a fire with is that flows are spreading out and slowing down. minimal harmful effects. Land managers and natural This raises the water table and increases the moisture resource professionals then monitor the effects of the content of the streamside vegetation. fire. The goal of many prescribed burns is to break up continuous fuel loads so that when fires occur they are less severe. Treated areas also act as firebreaks, aiding in fire suppression activities. Suppression of fires is a key tool used to manage riparian areas in order to protect big riparian trees and the aquatic habitats which are home to many rare species in the southwest. Long continuous stands of thick vegetation, especially salt cedar, can carry fires that are difficult to suppress due to fuel loads, access, and firefighter safety. Treating these areas when the fuel source is manageable enables fire managers to prevent large river areas and adjacent infrastructure from being impacted. Releasing pre-determined flows from dams, known as flood pulsing, is a possible management tool. Flood pulsing serves two purposes. First, in the Photo courtesy of the National Park Service short-term, flood waters can reduce fire frequency Beaver (Castor canadensis) and size by carrying away litter and woody debris

Chapter 6 83 Mechanical removal of litter and dead branches from the vegetation surrounding riparian areas is another tool land managers use to prevent large-scale fire events. This can be especially important in areas where highly flammable salt cedar is present in dense stands. These treated areas are called firebreaks. For example, the BLM uses firebreaks in strategic locations near wildland-urban interface areas to stop or check fires that may occur, or to provide a control line from which fire suppression activities can take place. This management practice decreases the occurrence of large, which not only damage riparian

areas but nearby infrastructure. Firebreaks also can be Photo courtesy of Bureau Land Management used as pretreatment areas for prescribed fire anchor BLM uses prescribed fire to create firebreaks in riparian areas. points. (Dwire and Kauffman 2003). Because riparian areas are highly valued as habitat for sensitive, threatened, and endangered species as with hoses in riparian systems. Resource advisors well as the for recreation, most fires are suppressed. help to determine whether post-fire rehabilitation Safeguards exist to ensure that suppression activities requirements are needed. do not further damage the site. For example, The use of biological controls (i.e. structured grazing retardant is not generally applied within 300 rotations with goats/sheep and use of insects) is being feet of a riparian system. No additives (foams or investigated as possible fuels management activities surfactants) are used in engines when applying water as well (David Repass, pers. comm).

Chapter 6 84 Riparian Literature Cited

Austin, D. and B. Wolf. 2001. Fire in Indian Naiman, R., H. Decamps, and M. Pollock. 1993. Country: two case studies in the southwestern The role of riparian corridors in maintaining United States. The Climate Assessment Project regional biodiversity. Ecological Applications. for the Southwest, Institute for the Study of 3: 209-212. Planet Earth. University of Arizona. CLIMAS Report Series CL1-01. Pavek, D. 1993. Juglans major. In: Fire Effects Information System, [Online]. U.S. Department Bahre, C. 1991. A Legacy of Change: Historic of Agriculture, Forest Service, Rocky Mountain Human Impact on Vegetation in the Arizona Research Station, Fire Sciences Laboratory Borderlands. Tucson, AZ, The University of (Producer). Available: http://www.fs.fed. Arizona Press. 231 p. us/database/feis.

Davis, G., Jr. 1982. Man and Wildfire in Arizona: Pater, Mark. Bureau of Land Management. The American Exploration Period 1824-1865. Personal communication with author. 12 Phoenix, Arizona: The Arizona Game and Fish December 2006. Commission. p. 156. Reed, W. 1993a. Fraxinus anomala. In: Fire Effects DeBano, L. and D. Neary. 1996. Effects of fire Information System, [Online]. U.S. Department on riparian systems. In: Ffolliott, P.; DeBano, of Agriculture, Forest Service, Rocky Mountain L.; Baker, M., Jr.; Gottfried, G.; Solis-Garza, Research Station, Fire Sciences Laboratory Gilberto; Edminster, C.; Neary, D.; Allen, L.; (Producer). Available: http://www.fs.fed. Hamre, R., technical coordinators. Effects us/database/feis. of Fire on Madrean Province Ecosystems: A Symposium Proceedings. General Technical Reed, W. 1993b. Salix gooddingii In: Fire Effects Report RM-GTR-289, Fort Collins, CO: U.S. Information System, [Online]. U.S. Department Department of Agriculture, Forest Service, of Agriculture, Forest Service, Rocky Mountain Rocky Mountain Forest and Range Experiment Research Station, Fire Sciences Laboratory Station: p. 69-76. (Producer). Available: http://www.fs.fed. us/database/feis. Dwire, K. and J. Boone Kauffman. 2003. Fire and riparian ecosystems in landscapes Repass, David. Bureau of Land Management. of the western USA. Forest Ecology and Personal communication with author. 15 Management. 178: 61-74. November 2006.

Kauffman, J., R. Beschta, N. Otting, and D. Lytjen. Rinne, J. and D. Neary. 1996. Fire effects on aquatic 1997. An ecological perspective of riparian and habitats and biota in Madrean-type ecosystems: stream restoration in the Western United States. southwestern United States. In: Ffolliott, P.; Fisheries. 22: 12-24. DeBano, L.; Baker, M., Jr.; Gottfried, G.; Solis- Garza, Gilberto; Edminster, C.; Neary, D.; Allen, Kauffman, J., M. Mahrt, L. Mahrt, and W. L.; Hamre, R., technical coordinators. Effects Edge. 2001. Wildlife of riparian habitats. In: of Fire on Madrean Province Ecosystems: A Johnson, D. and T. O’Neil, eds. Wildlife-habitat Symposium Proceedings. General Technical relationships in Oregon and Washington. Report RM-GTR-289, Fort Collins, CO: U.S. Oregon State University Press, Corvalis, OR. p. Department of Agriculture, Forest Service, 361-388. Rocky Mountain Forest and Range Experiment Station: p. 135-145. McPherson, Guy. University of Arizona. Personal communication with author. 11 November 2005.

Chapter 6 85 Shafroth, P., J. Cleverly, T. Dudley, J. Taylor, U.S. Fish and Wildlife Service. 2002a Southwestern C. Van Riper, E. Meeks, and J. Stuart. 2005. Willow Flycatcher Recovery Plan, Region 2, Control of Tamarix in the Western United Albuquerque, NM. States: implications for water salvage, wildlife use, and riparian restoration. Environmental USGS National Gap Analysis Program. 2004. Management. 35(3): 231-246. Provisional Digital Land Cover Map for the Southwestern United States. Version 1.0. RS/ Sher, A., D. Marshall, and J. Taylor. 2002. GIS Laboratory, College of Natural Resources, Establishment patterns of native Populus and Utah State University. Salix in the presence of invasive nonnative Tamarix. Ecological Applications. 12(3): 760- Williams, G. 1994. References on American Indian 772. use of fire in ecosystems. In: USDA Forest Service, Pacific Northwest Region. Portland, Steinberg, P. 2001. Prosopis glandulosa. In: Fire OR. Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Zouhar, K. 2003. Tamarix spp. In: Fire Effects Rocky Mountain Research Station, Fire Sciences Information System, [Online]. U.S. Department Laboratory (Producer). Available: http://www. of Agriculture, Forest Service, Rocky Mountain fs.fed.us/database/feis. Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed. Taylor, J. 2000. Populus fremontii. In: Fire Effects us/database/feis. Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed. us/database/feis.

Uchytil, R. 1990. Prosopis velutina. In: Fire Effects Information System, [Online]. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station, Fire Sciences Laboratory (Producer). Available: http://www.fs.fed. us/database/feis.

Chapter 6 86