Monitoring Wetland Ecological Condition

in the

Saint Mary River Watershed

Blackfeet Reservation, Montana

Prepared for the US Environmental Protection Agency, Region 8, Denver, Colorado

Blackfeet Environmental Office, Blackfeet Nation, Browning, Montana

Tara Luna, Mary Clare Weatherwax, and George Running Wolf, III

February 2016

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Saint Mary River Watershed Wetland Monitoring and Assessment (2014 and 2015)

Monitoring Project Overview

The Blackfeet Tribe has adopted a “no-net loss of wetlands” policy in accordance with Tribal and Federal regulatory standards. The US Environmental Protection Agency’s (EPA’s) Four Core Elements of Developing a Wetland Program are incorporated and implemented in this wetland monitoring and assessment project and the accompanying “Saint Mary River Watershed Management Plan”. Elements of the Tribe’s Wetland Program include: enforcement and regulatory standards, water quality monitoring and wetlands condition monitoring, wetland restoration, enhancement, protection and conservation. Nineteen wetlands were assessed during the 2014 and 2015 field seasons in the Saint Mary Watershed. Results will be used to identify conservation and restoration areas and, importantly, contribute to preserving and maintaining water quality in this watershed.

The Saint Mary River Watershed Area

Geology and Soils

Mountains of the Saint Mary and Many Glacier valleys in Glacier National Park are Pre-Cambrian sedimentary bedrock occurring above the Lewis Over-thrust Fault. Proterozoic rock of the Altyn and Greyson formations occur on the highest peaks on the Reservation watershed boundary. Bedrock of Hudson Bay Divide, along edges and ridges of the watershed, is overlain by Quaternary-age unconsolidated deposits of cobbles and Tertiary-age gravels (Cannon 1996). Younger deposits of Pleistocene and older Pliocene gravels occur in pediments and terraces that were reworked by more recent glaciation. Sediments, till, landslide debris and alluvium occur in valley bottom floodplains and stream corridors.

Wetland soils in the Saint Mary watershed typically have an organic layer that ranges up to 20 cm overlying silty gravels and cobbles and 26 to 46 cm overlying predominately clays, clay loams or silty clays. Clay layers often contain significant cobble or gravels, depending on location within the watershed. Histic soil peat layers range from 10 cm deep in forested spring systems near the western boundary of the Reservation near Chief Mountain to 2.4 m in a valley bottom fen found near Pike Lake.

Climate

Annual average precipitation in the Saint Mary Valley averages 61 cm (26.11 in) at Saint Mary to 46.5 cm (18.3 in) at Babb NE, with an average annual snowpack of 305 cm (120.3 in) at Saint Mary to 164 cm (64.5 in) at Babb NE (Western Regional Climate Center 2015). Mean January low temperature ranges from -10.5°C (13.1°F) at Saint Mary to -14°C (6.7 °F) at Babb NE, while the mean July high temperature ranges from 23.5° C (74.4 °F) at Saint Mary to 24.5°C (76.2 °F) at Babb NE.

Most recent estimates indicate that glaciers at the head of the Saint Mary watershed will be gone by 2030. Western Montana climate change models predict a 1.7° C (3.06° F) temperature

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increase in the area that includes the Blackfeet Reservation. Following analysis of 100 years of climate data in the area, cold temperatures decrease 20 days earlier and decline in number, whereas extremely hot days (≥32°C) show a 3-fold increase in number, with a 24-day increase in the seasonal window during which they occur (Pederson et al 2010). Average spring snowmelt dates, or onset of spring runoff pulse, occur on average in the region 20 days earlier, coupled with predicted decreases in average annual precipitation (USGCRP 2009). Increased frequency of heavy summer precipitation, coupled with warming temperatures, will contribute to more frequent or intensive flooding events.

Water and Hydrology

The watershed is fed by Blackfoot and Jackson Glaciers of the Saint Mary Valley and Grinnell and Swiftcurrent Glaciers in the Many Glacier Valley, permanent snowfields and annual snowpack. Headwater streams, alpine and subalpine lakes and a complex network of glacial groundwater from both valleys and Chief Mountain feed area potholes and riparian streams feeding into the Saint Mary River, Upper Saint Mary Lake and Swiftcurrent Lake and Sherburne Lake Reservoir, below Sherburne Dam.

Additional groundwater springs, within National Park valleys and near the base of Pleistocene glacial moraines along Hudson Bay Divide on the Reservation, are found in scattered locations. Groundwater-fed potholes are common at montane elevations and valley bottom elevations. Coarse-grained, unconsolidated deposits of alluvium gravel terraces and pediments, till and outwash occurring above bedrock are the only sources of potable water use in many areas of the Reservation, especially where these aquifer sources exist above impermeable shale and mudstone formations (Cannon 1996). These deposits are found in areas along ridges and terraces in the Saint Mary watershed.

Saint Mary forms the southernmost headwaters of Hudson Bay, and the Saint Mary River crosses the Canadian border near the Port of Piegan. Streams within the watershed include Divide, Wild, Boulder, Swiftcurrent, Willow, Otatso, Roberts, Kennedy and Lee Creek and smaller tributaries. Beaver influenced streams, ponds, willow scrub and riparian forests occur along many of the watershed’s streams. The Saint Mary River is bordered by black cottonwood (Populus balsamifera) dominated floodplain forest as well as extensive willow (Salix spp) dominated communities between upper and lower Saint Mary Lake. Upland forest bordering Lower Saint Mary Lake includes aspen parkland, mixed aspen/black cottonwood and lodgepole, spruce-subalpine fir and Douglas-fir forests. Major Reservation lakes of the watershed include Lower Saint Mary Lake, Sherburne Reservoir, Flat Top Lake, Duck Lake, Goose Lake, Spider Lake and Pike Lake.

Flora and Vegetation

Wetland and riparian flora and vegetation communities of the Saint Mary Watershed are highly diverse and include nearly all recognized wetland ecosystems found in Montana. Glacially carved, groundwater fed, forested depressional wetlands occur in high density in areas on the western edge of the watershed and Duck Lake vicinity. Alkaline and saline influenced prairie

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potholes, depressions and marshes occur within fescue dominated grasslands. Subalpine wet meadows, subalpine lakes and conifer forested springs occur near the boundary with Glacier National Park. Fens occur on toeslopes and valley bottoms near Lee Creek and Pike Lake. Concentrations of depressional wetlands are found in the Duck Lake, Kennedy Creek drainage and Chief Mountain area and at scattered locations in the Saint Mary River Valley near the Canadian border.

Forty-eight percent of all wetland vascular plants known to occur in Montana are found on the Blackfeet Reservation; including Montana Species of Concern, range-margin species and culturally important species. Some species are locally rare or uncommon in the Saint Mary watershed. Others are more broadly distributed or locally common, and are found throughout the watershed, in a range of wetland ecosystem types.

Fauna

Reservation wetlands and riparian areas are crucial to population maintenance, migratory patterns and dispersal of all wildlife species known to occur in the Northern Rocky Mountain ecosystem, as well as fauna restricted to the Northwestern Great Plains region.

Healthy beaver populations occur throughout the Park and Reservation watershed and provide critical functions for maintaining high water quality, retaining water catchment, storage and discharge, as well as providing a range of riparian hydro-periods that allow greater native wetland plant community diversity. Beaver complexes, due to varied habitat and cover, attract rich resident and migratory bird life. Area beaver influenced wetlands and riparian areas serve the vital purpose of maintaining water storage capacity and mitigating flood water events.

Beaver complexes also provide greater cover and secure travel corridors for other wildlife species, such as wolverine, grizzly bears, lynx and grey wolf, moose, deer and the Saint Mary elk herd. Due to dense woody vegetation typically associated with beaver wetland complexes, cattle impacts and invasive pasture grass and noxious species presence and cover tend to be minimal, emphasizing the quality of these riparian communities in the area.

The Saint Mary watershed is the only area east of the Continental Divide that contains Threatened bull trout, as well as supporting healthy populations of west slope cutthroat trout. Thirty-six other native fish species, including 5 additional Species of Concern are found in Reservation lakes, rivers and streams. Eight species of amphibians, including three Species of Concern, are found in Reservation wetlands. Area wetlands also support rich insect life, driving the pristine fisheries of the watershed as well as successful migratory songbird nesting that rely on the abundance of protein–rich larvae necessary for raising successful broods.

Recent Fire History of the Saint Mary Watershed

Two major wildfires occurred within the Saint Mary watershed during the past 13 years: the Fox Creek Fire (2002) and the Red Eagle Fire (2006). The Fox Creek Fire began as a lightning strike during an exceptionally hot and dry summer and burned several thousand acres in the Saint Mary and Milk River watersheds. The Red Eagle Fire (2006) burned a total of 34,000 acres of

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forest within the Saint Mary River watershed of the Reservation and Glacier National Park. Some wetland and riparian wetlands and streams, occurring on toe-slopes, were affected by post-fire sedimentation. During the summer of 2015, a 5,000 acre fire (Reynolds Creek Fire) occurred in the Saint Mary Valley in Glacier National Park, but did not cross the Reservation boundary.

Land Use

Land use in the Saint Mary River watershed, Blackfeet Reservation includes livestock grazing on native fescue prairie and forests, hay production and apiculture. Tourism, fishing, hunting, recreation and firewood cutting are also important sources of income to local residents. Visitation in Glacier National Park during the past 5 years has exceeded an average of 1.5 million visitors per year, with the Saint Mary and Many Glacier valleys being primary draws for tourist traffic, from June to early September. Local or shoulder season tourist traffic during spring and late fall are important tourist-based income supplements to area residents and businesses.

Logging has occurred in the watershed during the past 10 years following the Red Eagle and Fox Creek fires. Other agricultural based economy includes cattle ranching, lands leased for grazing and apiculture operations that rely on the watershed’s native flora for high quality honey production.

Monitoring Study Objectives

1) Collect baseline data of wetland ecological condition in the Saint Mary watershed, including water quality data, macro-invertebrate and vegetation sampling, to assess overall condition and function.

2) Determine impacts to wetland condition and water quality.3) Examine relationships between disturbances and wetland condition. 4) Utilize results to determine wetlands for protection, conservation and restoration.

Study Methodology

The Tribal Wetlands program used the Montana Natural Heritage Program’s Ecological Integrity Assessment methodology (MNHP 2014). Wetland assessments and monitoring data had been collected throughout the Reservation and specifically, in the Saint Mary River Watershed during 2009 Wetland Program work in collaboration with the Montana Natural Heritage Program, during the inception of protocol development. The protocol uses three levels of analysis: 1) Landscape analysis; 2) Qualitative Rapid Field Assessment and 3) Intensive Vegetation and Disturbance Indicator Assessments.

Site Selection

Sites were selected by probabilistic random sampling across the Saint Mary watershed to capture a range of wetland ecosystem types in varying states of ecological condition. See map Figure 1.

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Figure 1.

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Field Data Collection

Data was collected during the field season of July-August 2014 and 2015. A total of nineteen wetland sites were assessed using the Level 2 Rapid Method. Nine of the nineteen sites were also assessed using the Level 3 Intensive Vegetation protocol. Original target coordinates were used whenever possible, although 5 sites were shifted within 60 m of the original target coordinates. A total of 6 sites were selected that were greater than 60 m from target coordinates due to lack of accessibility. GPS and photo points were taken at each wetland assessment area and of the soil core and vegetation plot. One wetland soil core was collected per site to examine wetland soil layer features.

Four 10 meter square plots (quadrats) located along a 50 m transect line were used to sample and characterize wetland vegetation composition at each location. Quadrats were placed to capture the range of the structure and composition of wetland communities and to observe and record environmental variables at each site. Canopy cover values were collected and assigned for all vascular plant species as well as for litter, moss, lichen cover, standing water or bare rock cover.

A hand guide for visual estimate of cover class values was used to ensure precision, consistency, accuracy and repeatability each year during sampling and data collection.

Presence and stratum for each vascular plant species in the plots was recorded. Estimated canopy cover values and estimated cover of bare ground, open water, litter and moss, were assigned in each 10 square meter plot to one of the following classes: T=<1%, 2 = <1%, 3=1-2%, 4=2-5%, 5=5-10%, 6=10-25%, 7=25-50%, 8= 50-75%, 9=75-95%, 10= >95%.

Following data collection, the plant community was surveyed to record any additional species (residuals) that were not recorded within quadrats. Taxonomic identification and taxonomic nomenclature were determined from floras by Hitchcock and Cronquist (1987), Lesica (2012) and Flora of North America (1999-2015).

Data Analysis and Quality Assurance/Quality Control (QA/QC)

Data was entered into a MS Access database for analysis. Backup copies of all data were stored on external hard drives and jump drives.

Floristic Quality Assessments (FQI) scores were assigned by calculating the coefficients of conservatism values (C values) (Pipp 2015), ranging in score from 0 (exotics) to 10 (native taxa w/ high specificity), for all plant species occurring in plots.

Results

Nineteen Level 2 assessments were conducted in the Saint Mary Watershed during 2014 and 2015. Landscape, Physiochemical, Hydrologic and Vegetation metrics and disturbances were calculated to arrive at an overall mean Ecological Integrity Assessment (EIA) score for each wetland type. Total mean scores per wetland system type are shown in Table 1.

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Table 1: Mean EIA scores in the Saint Mary River Watershed

Wetland Ecological System No. Mean

Great Plains Prairie Pothole 6 84.5

Western Great Plains Closed Depression Wetland 2 82.0

Western Great Plains Open Freshwater Depression Wetland

1 76.4

Northern Rocky Mountain Forested Pothole 3 90.4

North American Western Emergent Marsh 1 95.0

Rocky Mountain Subalpine-Montane Riparian Shrubland 5 82.5

Rocky Mountain Wet Meadow 1 97.4

Physiochemical and Landscape

The nineteen wetlands sampled in the Saint Mary Watershed are in exceptional condition. Forested potholes, wet meadow, alkaline marsh and many of the depressional wetlands sampled scored 77 or higher (r-76.4-97.4).

Level 2 hydrologic metrics (hydroperiod, alteration and connectivity) had the highest score of all metrics measured, followed by physiochemical (water quality, soil surface integrity) and landscape metrics (connectivity, buffer width, length, condition, soils, trash). All sample sites scored high in surface water connectivity, and only two sites exhibited hydrologic alterations or hydroperiods. Soil surface integrity scored lower than water quality, due to grazing impacts. Only two wetlands that were sampled were located near agricultural fields or major roads.

Buffer condition, however, averaged lowest of the landscape metrics used, due to frequency of exotic weed cover and grazing impacts. Livestock grazing was the most frequent disturbance within wetlands and upland buffers. Scope and impact of livestock grazing in wetlands was low to moderate (10-25%) in all Assessment Areas (AA’s) as well as in surrounding upland buffers. Grazing intensity may vary considerably between landownerships. One sampled site was completely free of grazing impacts in the AA, with minimal grazing disturbances in the 200 m buffer.

Vegetation

Ninety five percent of wetlands contained native vegetation with cover values great than 95%, with one site completely free of non-native species. However, 50% of sampled wetlands

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contained at least some noxious weed species with cover values (>5%), most frequently, Canada thistle (Cirsium arvense) within the AA and spotted knapweed (Centaurea stoebe) in the upland buffer. Invasive graminoid cover values (>5%) were also encountered at 40% of wetland sites, with meadow foxtail (Alopecurus pratensis) and Garrison’s creeping foxtail (Alopecurus arundinaceus) being the most frequently encountered species with highest cover values (r 5-10%), followed by Kentucky bluegrass (Poa pratensis), timothy (Phleum pratense) and smooth brome (Bromus inermis).

Level 3 Intensive Vegetation

Floristic Quality Assessments (FQI) scores were assigned by calculating the coefficients of conservatism values (C values) (Pipp 2015), ranging in score from 0-1 (exotics) to 10 (native taxa w/ high specificity), for taxa occurring in plots, in nine sampled wetlands. The Floristic Quality Index (FQI) is calculated using the following formula:

Where is the mean C-value and N is the number of native species within the entire plot.

The FQI was calculated to a score that includes non-native species by the following:

Mean Floristic Quality Assessment scores were calculated for the Level 3 assessment sites. Results are shown in Table 2.

Table 2: Mean FQI Scores for Nine Sites in the Saint Mary Watershed

Wetland Ecological System No. MeanFQI

Min Max

Great Plains Prairie Pothole 3 42 37 45

Northern Rocky Mountain Forested Pothole 2 47 41.8 52.3

North American Western Emergent Marsh 1 51 - 51

Rocky Mountain Subalpine-Montane Riparian Shrubland 3 39.4 37 41.8

Beaver influenced, Palustrine Scrub-Shrub (PSS) associations contain an average of 22 (r 12-38) plant taxa, while non-beaver influenced, PSS associations contain fewer (14) taxa. Palustrine Emergent (PEM) herbaceous associations, associated with beaver complexes, exhibit greater species richness (24) than Great Plains prairie potholes and marshes (14) and forested

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depressions with PEM herbaceous associations (four). The forested pothole wetland, or kettle pond, is a pristine groundwater-fed site and fewer taxa are indicative of stable/later stage successional development. Submergent communities are more diverse in beaver ponds and forested potholes, averaging six taxa each, than Great Plains prairie potholes (four) and prairie marshes (two).

Booth’s willow/Northwest Territory sedge (Salix boothii/Carex utriculata) was the most frequently encountered plant association in forested areas, being encountered in all wetland systems sampled except Great Plains prairie potholes and closed depressions. Bebb’s willow/Northwest Territory sedge (Salix bebbiana/Carex utriculata) and Bebb’s willow/mixed graminoids or mesic forbs (Salix bebbiana/mixed graminoids or mesic forbs) tend to replace S. boothii/ C. utriculata in Great Plains potholes and depressions. These communities occur along the outer edge of the hydrologic influenced zone in fescue prairie wetlands. The most commonly encountered emergent plant community in all sites was Carex utriculata, while the most common open water emergent communities were dominated by various native pondweed (Potamogeton) species. A total of sixteen herbaceous emergent communities, five palustrine woody shrub, one palustrine forested and one submergent community were found in the nine Level 3 monitoring sites.

Discussion

Saint Mary Watershed Reservation wetlands have higher Wetland Ecological Integrity Scores than wetlands found east of the Reservation due to large, intact native buffers, lower (<10%) incidence of wetland hydrologic alteration, minimal paved and secondary roads, and absence of intensive logging and agriculture other than haying. The relatively narrow Saint Mary Reservation valley, topographic position of the watershed, higher precipitation levels and immediate proximity to Glacier National Park are contributing factors to higher EIA scores and FQI scores per wetland ecosystem type. Great Plains prairie potholes typically contain more taxa and plant associations in open water and emergent shoreline communities than potholes found further east of the Reservation in the western Prairie Pothole Region (PPR).

Similar to other EIA monitoring results from studies conducted in eastern Montana, livestock grazing is the most frequent disturbance, in scope and severity, both in wetlands and natural buffers. Overall, EIA non-native vegetation scores are indicative of not only grazing disturbance, but can also indicate warming temperatures that have led to decreased hydrologic periods for smaller, depressional wetlands, rendering them more susceptible to non-native invasion. Invasion by pasture grasses and noxious species further accelerates decreasing hydroperiod for smaller wetlands with temporary or seasonal hydroperiods. There are many examples of small closed depressions that have remained dry for many years since National Wetlands Inventory (NWI) mapping, have been invaded by upland native species, and contain low to moderate cover of only facultative (FAC) species.

Spread of non-native Alopecurus (foxtail) species in Reservation wetlands increases evapo-transpirational water loss and these species out-compete native emergent and submergents for nutrients and light. Stands can occur in a range of hydroperiods (semi-permanent to seasonal),

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water chemistry and wetland soil types. Importantly, these invasive graminoids tend to occupy the same hydrologic gradient as culturally significant sweetgrass (Hierochloe hirta) in riparian and depressional wetlands.

Application of Results

Data results have identified excellent condition wetlands that can be conserved through easement programs, as well as providing a prioritized list of wetlands that can be passively restored, with minimal financial restoration project needs. Recommended conservation easement sites for wetlands and associated upland buffers, occurring on Tribal, allotted and fee lands, are described in the supplemental Wetlands Conservation report (Luna 2015).

Many of these sites can also be petitioned for listing as Outstanding Tribal Resource Waters, due to exceptional water quality and ecological condition, or landscape location in proximity to the Tribal primitive area around Chief Mountain, Glacier National Park, wildlife management areas, identified travel corridors and pre-existing conservation easements. Kennedy Creek forested potholes are high quality, remote and some of the best examples of coniferous and aspen forested potholes on the Reservation. Forested, groundwater fed Reservation potholes in the watershed have previously been identified as high quality examples that have been largely impacted elsewhere in the aspen parkland belt.

Similarly, prairie potholes of the Reservation, due to their extent, abundance and condition, importance to migratory waterfowl, and relative species richness are considered some of the best remaining examples in the prairie pothole region (Lesica and Shelly 1988). Marshes occurring at low to mid elevations in the watershed exhibit a range of water chemistry, and consequently, a range of wetland flora and often contain more plant species than other examples in the Rocky Mountain and Great Plains regions. Saint Mary watershed contains groundwater fed springs and fens. Water chemistry is influenced by limestone and local examples contain several Species of Concern and other fen restricted taxa not found in other wetland ecosystems.

Routine wetland monitoring can provide additional vegetation data, locate undocumented wetland plant associations, rare and cultural species occurrences, and wetlands currently free of exotic species. These sites are not only conservation and protection candidates, but also provide reference condition data for wetland restoration of more impacted sites.

Vegetation monitoring results emphasize the need to implement a sound weed management strategy for Reservation wetlands, riparian areas, and lakes as well as upland prairie. Introduction of bio-control insects for spotted knapweed (Centaurea stoebe), throughout watershed wetlands areas, and leafy spurge (Euphorbia esula) in the Chief Mountain area are needed to preserve high water quality and improve wetland condition and function. Additional methods need to be investigated to control Canada thistle (Cirsium arvense) populations in watershed wetlands.

Collaborative weed management efforts are needed to manage noxious weeds in upland communities. It is hoped that reporting the frequency and spread of non-native foxtail

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(Alopecurus) species in Reservation wetlands strongly indicates the need to contain spread to non-infested wetland sites. Finally, the watershed is currently free of invasive woody species such as Russian olive (Elaeagnus angustifolia). Exclusion of these species is of paramount importance to preserve riparian functionality and riverine biodiversity.

EIA (Level 2) and Intensive (Level 3) methods and scoring have assisted the Tribal Water Quality and Wetlands Monitoring Programs to develop a routine, watershed-scale, wetland monitoring program and obtain data that can be correlated to specific wetland ecosystem types in a range of condition. Water quality standards differ among wetland ecosystem types and continued wetland water quality data collection will enable the development of watershed specific wetland water quality standards. Results can also address water quality concerns and watershed related protection and management issues, as well as providing supporting data for the implementation of projects that support future water management in the Saint Mary watershed.

Recommendations for Future Wetland Monitoring Assessments

The MNHP method provides a sound rapid method to assess ecological condition, disturbance level and scope, as well as the composition, structure and species richness of wetland and upland plant associations. Vegetation plot size captures the range of hydroperiods that occur in depressional, submergent/emergent and scrub-shrub wetlands, as well as forested wetlands, riparian stream corridors and floodplains. Exotic plant narrative metrics account for presence and abundance of both state-listed noxious species and grasses known to be invasive in wetlands.

It is recommended, however, that additional metrics be added to the EIA Method, that score or account for 1) wetland cultural plant species presence and abundance, and 2) wildlife habitat use/detailed wildlife observations (species observed). Additional metrics can further assist Tribal and State personnel involved in road construction projects in locating additional conservation sites of importance to the local Tribal community, and assist in wildlife habitat and corridor conservation efforts.

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References

Blackfeet Tribe Surface Water Quality Standards and Anti-Degradation Policy. 2013. Blackfeet Environmental Office. Prepared for the US Environmental Protection Agency. 61 p.

Cannon, MR. US Geological Service. 1996. Geology and Groundwater Map of the Blackfeet Reservation, Northwestern Montana.

Flora of North America, (FNA). 1993-2011. Published volumes and online treatments. Oxford University Press. (London and New York).

Hitchcock CL and Cronquist A. 1987. Flora of the Pacific Northwest. University of Washington Press. Seattle (WA) 343 p. ISBN 0-295-95273Lesica P. 2012. Manual of Montana Vascular Plants. Britt Press. Fort Worth (TX) 771 p. ISBN: 13-978-1889878-39-3

Lesica P and S Shelly. 1988. The vegetation and flora of glaciated prairie potholes on the Blackfeet Indian Reservation, Montana. Progress Report. The Nature Conservancy Montana/Wyoming Field Office. Helena, MT. 19 p.

Luna, T. 2015. Wetland and Riparian Conservation, Blackfeet Reservation. Report prepared for the Blackfeet Tribe and US Environmental Protection Agency. 24 pages.

Montana Natural Heritage Program. 2014. Wetland Assessment Protocol. Helena, MT. 55 p.

Pederson GT, Graumlich L, Fagre D, Kipfer T, Muhlfeld C.. 2010. A century of climate and ecosystem change in Western Montana: what do temperature trends portend? Climate Change 98: 133-154.

Pipp, A. 2015. Coefficients of Conservatism for the Flora of Montana. Part 1. Montana Natural Heritage Program. Helena, MT. Prepared for the MT Dept. of Environmental Quality. 60 p.

US Global Change Research Program. Karl T, Melillo JM, and Peterson TC (editors). 2009. Global Climate Change Impacts in the United States. Cambridge University Press. 189 p.

Western Regional Climate Center. 2015. (URL: http://www.wrcc.dri.edu/)

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