1	INTEGRATING ASPEN MANAGEMENT Dr. John G. Carter Utah Director Western Watersheds Project
2	Importance of Aspen 8 of 19 Sensitive Species Associated with Aspen and Conifer (USDA 1999) Second only to riparian in biodiversity (Bartos and Campbell 1998) Enhance watershed capacity by storing 7 times more water than conifers which replace them (Bartos and Campbell 1998)
3	Overview of Management Main threats to aspen are conifer invasion, fire exclusion and browsing Typical restoration techniques include prescribed fire, harvest, mechanical root stimulation, thinning of conifers, protection from browsing (Shepperd et al 2004) Although research shows that grazing is a causative factor in limiting cool ground fires, removing aspen suckers and increasing conifer recruitment, it is largely omitted from consideration
4	Aspen Research Bartos and Campbell (1998) - 60% decline in aspen in the six National Forests in Utah. “Changes in the abundance of aspen dominated landscapes have occurred over the past 125+ years partly as a result of livestock grazing, wildlife use and a reduction in fires. The historical fire regime was altered in the mid-1800’s after European settlement. Fire exclusion resulted from a combination of excessive grazing, timbering, and people extinguishing wildland fires. Grazing removed the fine fuels which generally carried the fires.”
5	"Kay and Bartos (2000" Kay and Bartos (2000) evaluated existing aspen exclosures on the Dixie and Fishlake National Forests in Utah. These were studied to determine the effects of livestock, deer and elk on aspen regeneration and associated vegetation. Aspen within all total exclusion plots successfully regenerated without the influence of fire or other disturbance. Aspen subject to browsing by wildlife regenerated at stem densities (2498/ha) significantly lower than on total exclusion plots (4,474/ha). On combined use plots, most aspen failed to regenerate successfully or did so at low densities (1,012/ha).
6	"Kay (2001" Kay (2001) studied hundreds of clones in central Nevada and found: Where livestock, not wildlife excluded, aspen were maintained Most herbivory of aspen was from livestock Aspen on slopes and further from water were in better condition Concludes for central Nevada, single aged stands are a result of livestock herbivory, not fire exclusion, conifer invasion, wildlife or climate change
7	Conifer Research Kreuger and Winward (1974) - forest stands suffered “retrogression” when grazed by cattle and big-game, but big-game grazing alone did not result in significant effects. Zimmerman and Neuenschwander (1984) - livestock grazing in Douglas-fir communities in Idaho caused increased tree numbers, decreased production, cover and frequency of major palatable grasses, and altered dominance of shrub and forb species. Grazing resulted in increased accumulation of downed woody fuel in every size class and decreased herbaceous fuels.
8	"Rummell (1951" Rummell (1951) - Ungrazed Meeks Table and grazed Devils Table in Washington. Herbaceous vegetation ranged from 183% to 254% greater on the ungrazed site “While the timbered overstories on the two Tables were similar, Meeks Table had only a very few small trees, but Devils Table had 3291 small trees per acre.” Madany and West (1983) - Grazed and ungrazed Ponderosa pine forest in Zion National Park. “Heavy grazing by livestock and associated reduction of the herbaceous ground layer promoted the establishment of less palatable tree and shrub seedlings.
9	"GAO summarizes the causes of..." GAO summarizes the causes of these problems as due to extensive livestock grazing beginning in the 1800’s which eliminated much of the grass that historically carried fire through the forest’s undergrowth, timber harvest practices of selective logging larger trees or clearcutting and increases in nonnative plants, insects and diseases. These factors generally changed the forest’s ecologies and the primary factor compounding the damage was fire suppression.
10	Intermountain Regional Assessment 85% of aspen in R4 in mid- to late seral 41% in Idaho succeeded to other type Causes: Exclusion of fire and livestock grazing Livestock grazing reduced fine fuels resulting in lower fire spread Regeneration not successful due to heavy grazing by livestock Lack of regeneration leads to conifer invasion
11	Typical Aspen Projects Do not address cause and effect of grazing as related to lack of regeneration or conifer invasion Provide no baseline information on regeneration, herbaceous understory condition, levels of browsing or livestock utilization Generally propose 2 years of rest post treatment before bringing livestock back, no fencing to protect regrowth Provide no annual monitoring of browsing and herbaceous vegetation utilization to direct livestock management and produce multiple age classes over time
12	What Else is Missing? Role of predators Relative importance of wildlife vs livestock Role of grazing management Capability Forage capacity Stocking rate Water developments Adequate rest
13	Role of Predation Beschta (2003) – correlated loss of cottonwood recruitment with extirpation of wolves and increased elk browsing in YNP. Ripple and Beschta (2006) – demonstrated the loss of cottonwood recruitment and riparian degradation in Zion NP where cougar populations have been eliminated, resulting in deer consumption of cottonwood seedlings. In areas with cougars, healthy riparian areas and cottonwood recruitment occur. Ripple and Beschta (2004) - postulated the elk/wolf relationship in YNP will rebalance plant community structure, including aspen. Hebblewhite et al (2005) – In Banff NP, wolf exclusion decreased aspen recruitment, willow production and increased browsing intensity. Ripple and Larsen (In Press) – Aspen decline associated with removal of wolves in YNP
14	Wildlife vs Livestock Many studies don’t clarify livestock grazing management that removes forage needed by elk and deer, ignoring the resulting “ice cream” effect in which elk or deer consume aspen suckers because little of their preferred forage is left. Elk rely on herbaceous vegetation¹, deer consume herbaceous vegetation spring, summer and fall². In Utah, forage consumed by livestock on public lands could support over 2,000,000 deer or 500,000 elk annually³. Utah’s current elk population is 60,000⁴.
15	Grazing Management
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18	Pleasantview Allotment
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22	Water Developments Holechek et al (2001) – Sacrifice areas occur around developments, resulting in loss of ecological condition. “Regrettably, we have observed the degradation of many publicly owned, high condition rangelands when permanent water developments were installed.” Bear River Range, for example
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30	Caribou NF Draft Plan/EIS Riparian – 30% PFC,70% non-PFC Conifer – 60 – 70% Douglas fir mature with increasing stand density, ladder fuel Aspen – 25% lost due to fire suppression, grazing, conifer encroachment Sage/grass – Increasing canopy, diminishing grasses, shift to undesirables
31	Bear River Range Study Chard and Carter (2001) surveyed 86 locations using Forest PFC criteria, found:
32	Upland Grazing Hormay and Talbot (1960) Rest Rotation – 3 yrs rest out of 5 with deferment the other two Mueggler (1975) Idaho fescue of moderately low vigor required 3 years of rest for recovery and bluebunch wheatgrass and Idaho fescue in very low vigor may require 8 years and 6 years of rest, respectively for recovery.
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36	Riparian Grazing Duff (1977) – Degraded riparian areas require a minimum 6 to 8 years rest for recovery Clary and Webster (1989) – Degraded riparian areas may require complete rest to initiate recovery Chaney, Elmore and Platts (1993) – Three pasture rest-rotation is often detrimental to riparian tree seedlings. Livstock can consume two or three years growth in one summer grazing period. Kovalchik and Elmore (1991) – Three or more years rest needed for heavily used willows to recover My own property after 10 - 12 years rest – plant community, aspen, willow, dogwood, alder healthy, stream banks and instream habitat require much more time.
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40	Conclusions Water developments and overstocking with livestock are a key factor in conifer invasion, suppression of aspen regeneration and loss of herbaceous understory. Loss of predators has been implicated in loss of aspen.
41	Recommendations Remove water developments within ½ mile of aspen sites Assess capability and current forage capacity Set proper stocking rate based on sustainable use rates and consistent, accurate monitoring Provide multiple years’ rest to restore productivity of native plant communities, riparian areas and aspen, then follow Hormay’s recommendation for rest 3/5 years (except for riparian, which must be addressed separately) If wildlife browsing is a problem, place emphasis on predator/prey interactions by halting predator control and employ hunting to control populations Employ treatments for aspen following Mueggler’s Scheme
42	"Western Watersheds Project would participate..." Western Watersheds Project would participate with and offer our assistance to the AWG in development of an effective method for restoring aspen if there is a will among the participants to employ a systematic, science-based approach that includes effective livestock management to restore aspen and associated habitats