Caribou National Forest Riparian Grazing Implementation Guide Version 1-2
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Caribou National Forest Riparian Grazing Implementation Guide Version 1-2 Riparian Process Paper By R.L. Leffert Forest Hydrologist, Caribou/Targhee National Forest 7/03/2002 Updated 12/28/2005 1 Table of Contents Page Introduction…………………………………………………………………. 4 Streamside Vegetation and Channel Morphology……………………….. 6 Grazing Strategies in Riparian Areas……………………………………. 9 Monitoring Parameters…………………………………………………… 12 Stubble Height…………………………………………………….. 12 Percent Plant Utilization…………………………………………… 16 Bank Disturbance………………………………………………….. 19 Soil Disturbance……………………………………………………. 24 Riparian Zone ground cover and plant utilization………………. 27 Factors and Techniques that Affect the Distribution Of Livestock and Resource Impacts……………………………………… 30 Table A – Management Practices and Expected Benefits………………. 34 Water Quality and Aquatic Habitat……………………………………… 36 Table B - Grazing Strategies and Stream/Riparian Habitats…………… 38 Impact Guidelines…………………………………………………………. 39 Goal…………………………………………………………………. 40 Implementation…………………………………………………….. 41 Similarity……………………………………………………. 41 Resiliency……………………………………………………. 42 Table 1 – Greenline Key Species Forage Utilization……………... 45 Table 2 - Woody/Shrubby Species Utilization …………………… 45 Table 3 –Greenline Stubble Height ………………………………. 46 Table 4 - Riparian Zone Soils Disturbance ……………………… 46 2 Table 5/5A - Bank Alteration/Stability….. …………………………… 47 Table 6/6A – Riparian Zone Utilization and Stubble Heights………. 48 Key to Determine Allowable Use Parameters……………………………........ 49 Figure 1 - Succession of States for Alluvial/Nongraded Valley Bottom Types . 59 Ecological Status of Riparian Vegetation……………………………………… 60 Table 7 - Stream Channel Characteristics…………………………………… 61 Figure 2 - Rosgen Channel Classification Table……………………………... 62 Table 8 - Riparian/Stream Channel Morphology Objectives……………….. 63 Monitoring……………………………………………………………………… 66 Field Guide for Measuring Riparian Area Impacts…………………………. 69 Streambank Alteration……………………………………………....... 72 Stubble Height…………………………………………………………. 74 Forage Utilization………………………………………………………. 75 Willow Utilization……………………………………………………… 76 Woody Species Regeneration…………………………………………. 77 Riparian Soil Disturbance…………………………………………….. 78 Glossary………………………………………………………………………… 80 References……………………………………………………………………… 83 3 Riparian Monitoring Parameters and Management Systems Introduction of the landscape, they are important for a variety of reasons (Chaney, et al 1991, US Riparian areas are those lands adjacent to GAO 1988). Vegetation found within these water bodies that are considered to be the areas not only provides habitat for wildlife transition between water bodies (aquatic species but exercises important controls over systems) and uplands (terrestrial systems). physical and biological conditions and They have distinct vegetation and soil functions in the stream environment. characteristics that are influenced by high water tables or the presence of near-surface Vegetation acts as a roughness element that water. Riparian ecosystems are characterized reduces the velocity and erosive energy of by a combination of high species diversity water flowing down the channel, reducing and densities and high productivity. not only channel erosion, but assisting in Continuous interactions occur between reducing peak flow levels and improving low riparian, aquatic and adjacent terrestrial flows (Fitch and Adams, 1998). Riparian ecosystems through exchanges of energy, vegetation produces the bulk of the detritus that provides up to 90 percent of the organic nutrients and species (Windell, et al, 1986). 1 matter and 99 percent of the energy necessary to support headwater stream communities. Stream systems develop a dynamic Large woody debris and other obstructions equilibrium with the variables of climate, assist in the detention and concentration of geology, vegetation and surrounding land organic matter locally, rather than being uses. Any change in any one of these washed downstream, and serve as substrates variables can evoke an adjustment response for microbial and invertebrate organisms. in streams and their valleys (Fitch and Adams, 1998). Nelle (2004) found that a Riparian vegetation also provides shade that properly functioning creek, along with its moderates water temperature fluctuations. riparian floodplain can help ameliorate and The roots of trees, shrubs and herbaceous buffer irregular pulses of water over space vegetation assist in stabilizing streambanks, and time and can help keep water more provide cover for wildlife and act as a filter evenly distributed on the land longer. He to reduce or prevent upslope sediment from stated that the essence of riparian function is entering the stream system (Kaufman et al to efficiently catch, store and release 1984). floodwaters, while capturing sediment and improving water quality. Even though these Cattle may spend from five to thirty times the lands may make up a minor (1%-2%) portion amount of time in riparian areas as in adjacent xeric upland areas. Factors for this 1In Mosley, Jeffrey C., Philip S. Cook, Amber J. disproportionate time include: higher forage Griffis, and Jay O'Laughlin, Guidelines for Managing volume and relative palatability of riparian Cattle Grazing in Riparian Areas to Protect Water plant species; distance to available water; Quality: Review of Research and Best Management distance upslope to upland grazing sites; and Practices Policy , Report No. 15, Idaho Forest, microclimatic features (Clary & Webster Wildlife and Range Policy Analysis Group, University 1989). of Idaho, 1997, pg.6. 4 This is not to say that grazing is totally Laycock (1994) 4 suggested that many incompatible with riparian areas. In fact, vegetation types on public lands are currently proper grazing may co-exist with sustainable in a stable state condition and even if riparian systems (Larsen et al 1998; Elmore livestock were completely removed, overall & Kauffman, 1994 2; Buckhouse 2000; watershed condition would change little. Armour, et al , 1994), or even in some cases Green and Kauffman (1995) found that after is beneficial for plant density and vigor, ten years of non-grazing in dry meadows, which assists in stabilizing soil, slowing bluegrass remained the most dominant erosion and decreasing in-stream sediment species while the abundane of other species (WDEQ 1997). Leonard et al (1997) also declined. In moist meadows, they found found that livestock grazing can be a Carex rostrata to remain dominant, while compatible use in riparian areas when other species declined. managed in harmony with land management objectives, and when the function, capability, However, literature suggests that if excessive and potential of the site and the needs of the disturbances are allowed to continue through riparian vegetation guide the development of improper management, detrimental impacts the grazing management prescription. may outweigh benefits (Clary & Webster 1989). Mathews (1996) found that trout For example, in a Kentucky bluegrass density and biomass per unit area were meadow peak production occurred after six significantly higher in ungrazed than in years of rest then declined until production grazed areas in three of four comparisons. was similar to that in an adjacent area grazed She found that ungrazed areas consistently season-long (Clary & Webster 1989). In had greater canopy shading, stream depths other studies, removal of apical dominance in and bankfull heights and smaller stream grass tillers caused more shoots to grow, widths than grazed areas. Effects of adverse resulting in a thickening of the grass stand grazing impacts can be long lasting, requiring (Mosley et al 1997). Hayes (1978) 3 found a channel system to evolve through an that in the absence of livestock utilization, evolutionary process that may take a species richness and species diversity significant period of time (Rosgen 1996). decreased in dry and moist meadow communities. In “brittle” environments, The effects of livestock grazing on riparian especially those in low rainfall areas, Savory areas, including stream channel stability, (1999) found that lack of grazing actually had aquatic habitat, and water quality, have been a worse impact on some upland watersheds studied and documented by numerous than grazing. Under certain circumstances authors. Most agree that livestock can and do he found the grassland vegetation either have impacts if improperly managed and can shifts toward woody vegetation and “weeds” adversely affect the general characteristics or to algae and lichens if not grazed. and functions of riparian areas (Chaney et al 1991; Fitch and Adams 1998). Belsky et al (1999) concluded there were no positive 2 In Vavra, Martin, William A. Laycock and Red D. effects of grazing and, at best, grazing had Pieper eds. 1994. Ecological Implications of Livestock neutral effects. He found that livestock Herbovory in the West. Society for Range grazing negatively affects water quality and Management, Denver, CO. seasonal quantity, stream channel 3 In Green, DM. and Boone Kauffman. 1995. Succesion and livestock Grazing in a Northeastern morphology, hydrology, riparian zone soils, Oregon Riparian Ecosystem. Journal of Range Management. 48:307-313. 4 Ibid 5 instream and streambank vegetation, and Goodheart Creek, located on the Caribou aquatic and riparian wildlife. National Forest after a reach was protected from grazing by fencing (Leffert, 2000). Effects include: EPA (1994) has also summarized grazing • Higher stream temperatures from lack effects