United States Department of Agriculture Forest Service Agua Fria Grasslands Improvement Project Draft Environmental Assessment
Verde Ranger District, Prescott National Forest Yavapai County, Arizona September, 2015
Cover Photo: Grasslands outside of Dugas, Arizona; photo credit Max Wahlberg
For More Information Contact:
Todd Willard Verde Ranger District
300 E. Hwy 260 Camp Verde, Arizona 86322 Phone: (928) 567-1130 Email: [email protected] Fax: (928) 567-1179
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Contents Contents ...... i Introduction ...... 1 Proposed Project Location ...... 1 Need for the Proposal ...... 3 Public Involvement and Tribal Consultation ...... 3 Proposed Action and Alternatives ...... 4 Background ...... 4 No Action ...... 5 Proposed Action ...... 5 Mesquite and Catclaw Treatment Alternative ...... 9 Alternatives Considered but Eliminated from Detailed Study ...... 10 Environmental Impacts of the Proposed Action and Alternatives...... 10 Vegetation ...... 10 Wildlife ...... 22 Soils and Watershed ...... 37 Fuels and Fire Behavior ...... 67 Transportation ...... 71 Cultural Resources ...... 73 Recreation and Scenic Resources ...... 76 Livestock Grazing ...... 84 Finding of No Significant Impact ...... 90 Context ...... 90 Intensity ...... 90 References ...... 93 Appendix A...... 94 Appendix B...... 98 Existing Condition ...... 98 Desired Future Condition ...... 98 Treatment Objectives ...... 98 Silvicultural Treatments ...... 99 Best Management Practices and Protection Measures ...... 99 Future Management ...... 100 Appendix C...... 101 Appendix D...... 103 Appendix E...... 105 Map 1. Agua Fria Proposed Vegetation Treatments ...... 105 Map 2. Agua Fria Transportation Proposed Actions...... 106 Map 3. Agua Fria Mesquite Treatment Areas ...... 107
i
List of Tables
Table 1. Proposed vegetation treatments ...... 5 Table 2. Proposed transportation actions ...... 7 Table 3. Vegetation Types within the Agua Fria Project Area ...... 11 Table 4. TE&S Species occurrences in the Agua Fria Assessment Area...... 23 Table 5. Ash Creek / Sycamore Creek 5th and 6th Code Watershed Acres ...... 41 Table 6. Bishop Creek 5th and 6th Code Watershed Acres ...... 41 Table 7. Agua Fria Overall Watershed Condition Assessment ...... 42 Table 8. Sub-watershed conditions, by indicator ...... 42 Table 9. Cienega Creek soil condition ratings ...... 43 Table 10. Dry Creek soil condition ratings...... 44 Table 11. Little Ash Creek soil condition ratings ...... 45 Table 12. Lower Ash Creek soil condition ratings ...... 46 Table 13. Little Sycamore Creek soil condition ratings ...... 47 Table 14. Sycamore Creek soil condition ratings ...... 48 Table 15. Indian Creek soil condition ratings...... 49 Table 16. Silver Creek soil condition ratings ...... 50 Table 17. Bishop Creek soil condition ratings ...... 50 Table 18. Allotments within the Agua Fria project area ...... 85
ii Verde Ranger District, Prescott National Forest
Introduction This project proposes a set of vegetation treatments that are expected to provide benefits across multiple resource areas. The treatments include the use of fire and mechanized equipment to open up the tree canopy and maintain desired conditions on approximately 89,000 acres. These actions would be implemented in the Agua Fria grasslands area on the Verde Ranger District of the Prescott National Forest (Prescott NF).
Fire has played an important ecological role in the history of the grassland, woodland, and forest ecosystems of Arizona. Historically, regular intervals of naturally occurring fire have restricted the growth of shrubs in grasslands, thinned forests of fire-intolerant trees, increased stream flows, and renewed wildlife habitat. Since the beginning of the early 20th century, the frequency of natural fire has decreased dramatically. This decrease has corresponded with increased fire suppression to protect life and property, and the reduction of fine fuels by livestock grazing.
Current conditions allow uncontrolled wildfires to eliminate desired ecosystem components, facilitate the establishment of unwanted non-native species, and result in dramatically different effects on watersheds than what would have occurred with natural fire. The most recent prescribed burning in the Agua Fria grasslands was in 2001, after which the onset of drought caused the practice to be discontinued pending more suitable climatic conditions. In 2005 the Butte Fire burned about 8,000 acres, most of which was in the grasslands. The same year, the Cave Creek fire also burned through the area on the east side of Forest Road 677 from the south forest boundary to Sycamore Creek. Fuelwood sales were used to thin juniper near Grassy Mountain, Brushy Basin, Cedar Tank and Mill Point Tank; however, with the declining use of wood for heat, no sale areas have been offered since the early 1990s.
This environmental assessment (EA) was prepared to determine whether implementation of mechanical and wildland fire (both prescribed fire and managed wildfire) vegetation treatments may significantly affect the quality of the human environment and thereby require the preparation of an environmental impact statement. This EA fulfills agency policy and direction to comply with the National Environmental Policy Act (NEPA). For more details of the proposed action, see the Proposed Action and Alternatives section of this document.
Proposed Project Location
The Agua Fria Grasslands Improvement Project is situated on the eastern edge of the Verde Ranger District south of Camp Verde on the Prescott NF (see figure 1.). The project area comprises approximately 89,000 acres bounded by Interstate 17 on the west, Pine Mountain and Cedar Bench Wilderness Areas to the east and the Tonto National Forest and Bureau of Land Management (BLM) Agua Fria National Monument (AFNM) to the south. It spans portions of nine 6th code sub-watersheds in two 5th code watersheds: Ash Creek / Sycamore Creek and Bishop Creek. The vegetation is primarily piñon pine, juniper, and semi-desert grasslands.
1 Agua Fria Grasslands Improvement Project
Figure 1. Agua Fria project location
2 Verde Ranger District, Prescott National Forest
Need for the Proposal This proposal is needed because, although much of the Agua Fria grassland is still fairly open, drought and a lack of fire have led to a departure from the desired vegetation structure and fire regime and a decline in the quality of wildlife habitat and watershed functionality. These changes include encroachment by trees and shrubs, loss of perennial grass cover, and an increase in exposed soil surface. The Forest Service proposes to maintain or improve watershed function, vegetation conditions, and natural fire regime to move the landscape toward desired conditions described in the 2015 Land and Resource Management Plan for the Prescott National Forest (Forest Service, 2015) (hereinafter referred to as the Forest Plan) and improve wildlife habitat for pronghorn antelope, threatened or endangered fish species, yellow billed cuckoo, and migratory birds. The treatments, which will consist primarily of juniper thinning and prescribed burning, will also improve the function of the watershed by increasing the forb and grass components, thereby reducing soil movement and increasing water quality and quantity available for wildlife and riparian communities.
Key to the implementation of this project is the Central Arizona Grasslands Conservation Strategy (CAGCS). As noted in the charter of the CAGCS (Arizona Game and Fish Department, 2014), the Prescott NF is operating under the regionally-directed “Central Priority”. This direction emphasizes the restoration of fire adapted ecosystems, of which grasslands are a major component. Pronghorn were identified in the Forest Plan as a Management Indicator Species (MIS) for grassland ecosystems to act as an umbrella to represent a whole suite of species with related habitat needs. In addition to this restoration effort, there is a desire to promote the grassland ecosystem as a living laboratory for environmental education and research.
The actions proposed will support an upward trend towards Forest Plan desired conditions for ecosystem resilience (DC-Ecosystem Resilience- 1), vegetation (DC-Veg- 1, 3 to 8, -11, -12, & - 21), wildlife (DC-Wildlife- 1 & -2, DC-Aquatic- 1 to 3), watersheds (DC-Watershed- 1 to 4, & - 5), and airsheds (DC-Airsheds- 1) in the Forest Plan. This project will carry out direction supplied in objectives for vegetation (Obj- 1, - 3, & - 4), watersheds (Obj- 21 & 23), and wildlife (Obj- 26), and will comply with the appropriate standards and guidelines detailed in chapter 4 of the Forest Plan.
Public Involvement and Tribal Consultation The proposal was listed in the Schedule of Proposed Actions beginning in April 2013. The proposed action was provided to the public and other agencies for comment during scoping that began on February 21, 2013. The schedule of proposed actions is available on the Prescott NF website at http://www.fs.fed.us/sopa/forest-level.php?110309.
During the scoping period, the Prescott NF notified the following Native American tribes, nations, and communities:
Yavapai Prescott Indian Tribe in Prescott, Arizona
Yavapai Apache Nation in Camp Verde, Arizona
3 Agua Fria Grasslands Improvement Project
Fort McDowell Yavapai Nation in Fountain Hills, Arizona
Hopi Tribe tribal office in Kykotsmovi, Arizona
Hualapai Tribe in Peach Springs, Arizona
Tonto Apache Tribe in Payson, Arizona
The Prescott NF hosted an open meeting with livestock grazing permittees on February 21, 2013 to discuss the project. The Prescott NF has also coordinated with the Arizona Game and Fish Department during the development of the proposed action.
Six responses were received during the scoping period for this project, and no issues were raised that caused the project proposal to be substantially modified. Some comments and suggestions were incorporated into the Environmental Analysis as project design features or mitigations. No comments on the proposed action were received from Native American groups during or after the scoping period.
Input received from landowners and grazing permittees in February, 2014, after the scoping period, led to a change in the proposed action. The original proposed action is described below as the “Alternative that restores public access to the Marlowe Mesa area” in the section Alternatives Considered but Eliminated from Detailed Study.
Proposed Action and Alternatives Background
In the Forest Plan, terrestrial ecosystems on the forest have been classified into potential natural vegetation types (PNVTs) based on similar units of vegetation, soil, climate, and disturbance at a landscape scale. PNVTs represent the vegetation type and characteristics that would occur when natural disturbance regimes and biological processes prevail. The PNVT classifications were developed from data available in the Terrestrial Ecosystem Survey of the Prescott National Forest (Robertson et al., 2000) and from information on vegetation dynamics and natural variability compiled by The Nature Conservancy and the Landscape Fire and Resource Management Planning Tools Project (commonly called LANDFIRE).
Since the completion of the Terrestrial Ecosystem Survey of the Prescott National Forest (TES), the process name has been changed to the Terrestrial Ecosystem Unit Inventory (TEUI); this avoids confusion with Threatened and Endangered Species (TES).
Whereas PNVTs represent similar units at a landscape scale, TEUI map units represent similarity at a finer scale based on soils, landform, topography, slope, geology, climate, and vegetation. As such, they can be used to refine the prescription for treatments within the PNVTs.
The proposed action and following alternatives were considered:
4 Verde Ranger District, Prescott National Forest
No Action
This represents the existing and projected future condition against which the action alternatives are compared. Although there would be no action to treat vegetation under this alternative, existing activities in the Agua Fria Grasslands project area such as road maintenance, wildfire management of natural ignitions, firewood cutting, livestock grazing, hunting, and recreational activities would continue.
Proposed Action
Vegetation Treatments
The proposed action contains vegetation treatments in four potential natural vegetation types (PNVTs) that are expected to provide benefits across multiple resource areas. The acres proposed for treatment are listed in table 1 by PNVT; the proposed treatments include the use of fire in all four PNVTs and the use of mechanized equipment in Juniper Grassland to open up the tree canopy. The spatial distribution of these treatments is shown on the Agua Fria Proposed Vegetation Treatment map (map 1 – appendix E).
Table 1. Proposed vegetation treatments
Potential Natural Desired Treatment Existing condition Proposed Treatment type Vegetation Type condition Acres
Use fire to open canopy to < 30% 8,693 About 10,000 acres - multiple resource benefit in a closed tree canopy cover state Use fire to open canopy to < 30% Piñon-Juniper <30% canopy 2,233 - vegetation and fire benefit Evergreen Shrub cover from trees 47,4832 acres About 37,000 acres Maintain < 30% tree canopy with 24,578 at or near desired fire 30% tree canopy cover Fire avoidance areas 12,328
40% of the semi- desert grassland Use fire to reduce overstory 11,198 >10%canopy cover canopy to < 10% Semi-Desert 100% of the from trees or shrubs Grassland semi-desert grassland has 27,438 acres 60% of semi-desert woody canopy grassland has Maintain < 10% overstory canopy cover <10% <10% canopy cover with fire 16,240 from woody species.
<30% tree Hand thin and mechanical 3,241 canopy cover treatment to reduce cover Moderately departed from <5% canopy Juniper Grassland Hand thin and mechanical to desired conditions - cover for 4,149 revoke vertical structure 12,733 acres >30% tree canopy pronghorn cover Maintain with fire in addition to At DC 9,265 other mechanical treated areas
5 Agua Fria Grasslands Improvement Project
Table 1. Proposed vegetation treatments
Potential Natural Desired Treatment Existing condition Proposed Treatment type Vegetation Type condition Acres
Existing condition is at desired Interior Chaparral condition – state of transition from Maintain conditions with fire 1,056 young to older state
Piñon-Juniper Evergreen Shrub
The Piñon-Juniper Evergreen Shrub PNVT is moderately departed from desired conditions. Currently, about one-third of the Piñon-Juniper Evergreen Shrub in the project area is in a closed tree canopy cover state. The proposed action would open closed-canopy woodlands to less than 30 percent canopy cover from tree species and maintain this state. This would be achieved using managed wildfire or prescribed fire. This treatment would cover 10,926 acres, with 8,693 acres designated as first priority in the PNVT due to multi-resource benefits and 2,233 acres as second priority in the PNVT as it primarily benefits vegetation and fire.
An additional 24,578 acres would be improved or maintained through the use of managed wildfire or prescribed fire, focusing treatments in areas identified as vegetation overstory opportunities. These areas would be outside of the 12,328 acres of fire avoidance in TEUI 43, 430, and 479.
Semi-Desert Grassland
As noted in the Forest Plan, the Semi-Desert Grassland PNVT across the forest shows severe departure from desired conditions in both vegetation structure and fire regime. Currently, about 40 percent of the Semi-Desert Grasslands within the project area have greater than 10 percent canopy cover from trees or shrubs; the desired condition is that in 100 percent of the PNVT, woody canopy cover is less than 10 percent. This allows for the growth and retention of the fine fuels that provide for and maintain the desired fire regime. Fire historically occurred every 2 to 10 years in the Semi-Desert Grassland PNVT. The desired fire return interval is approximately every 10 to 15 years, and the Semi-Desert Grassland is within this interval due to the Butte Fire in 2005.
The proposed action would open the canopy cover on 11,198 acres to less than 10 percent and maintain this state. This would be achieved using managed wildfire or prescribed fire. This is the first priority in the PNVT as it would provide multi-resource benefits, including improvements to pronghorn habitat.
Second priority in the PNVT is the maintenance of open canopy conditions (less than 10 percent canopy cover) on 16,240 acres of Semi-Desert Grassland using managed wildfire or prescribed fire.
6 Verde Ranger District, Prescott National Forest
Juniper Grassland
Juniper grasslands are moderately departed from desired conditions due to fire exclusion. This has allowed for increases in the density and canopy cover of trees and shrubs and a reduction in fire stimulated regrowth and germination of perennial grasses and forbs. The desired fire regime is every 1 to 35 years with low severity favoring regrowth and germination of native grasses and forbs.
The proposal is to open the tree canopy in closed canopy woodlands to less than 30 percent with a combination of hand thinning and mechanical treatment on 3,241 acres of TEUI 490. This condition would be maintained with managed wildfire or prescribed fire.
This project also proposes to improve pronghorn habitat in juniper grasslands. In 4,149 acres of TEUI 427, the canopy cover would be reduced to less than five percent using a combination of hand thinning and mechanical treatment to remove vertical structure.
In addition, 9,265 acres, including the mechanical treatment acres, would be maintained with managed wildfire or prescribed fire. Treatments should limit fire impacts (fire avoidance) in 227 acres of TEUI 42 and avoid burning areas draining onto TEUI 427 until these sites have responded to mechanical vegetation treatments.
Interior Chaparral
The plant composition, structure, and fire regime found within the Interior Chaparral PNVT are similar to desired conditions – there is little to no departure. Interior Chaparral is in a constant state of transition from young to older stages and back again, with high severity fire once every 35 to 100 years being the major disturbance factor. The proposal is to maintain these vegetation conditions and fire regimes through managed wild fire or prescribed fire on 1,056 acres within TEUI 425 and 457.
Transportation
The proposed action also recommends several changes to the transportation system that are intended to improve terrestrial and aquatic wildlife habitat and restore watershed functionality by creating larger blocks of unroaded habitat and reducing erosion, sedimentation, and run-off from National Forest System roads to improve water quality and increase surface infiltration.
Table 2. Proposed transportation actions
Recommendation # of roads Total miles
Armor road 2 .7 miles
Convert to motorized trail 1 .7 miles
7 Agua Fria Grasslands Improvement Project
Table 2. Proposed transportation actions
Recommendation # of roads Total miles
Decommission Road 14 15.3 miles
Improve Level 1 to Level 2 1 .2 miles
Level 2 - restrict to authorized users 20 15.3 miles
Wet Weather Travel Restrictions 10 N / A
Access should be restricted to administrative use only on FR9601X for approximately one mile from the fence line west to I-17 from April 1st to June 30th to protect pronghorn fawning habitat.
Additional details regarding specific roads can be found in the Agua Fria Transportation Proposed Actions map (map 2 – appendix E) and appendix C - Transportation PA Details.
Exclosures and Springs
The proposed action contains two exclosure projects – one at the existing Reimer Spring exclosure and a new exclosure at Ash Springs.
Reimer Spring; gully stabilization includes the installation of Jersey barriers and other stabilization tools in the stream channel inside the existing exclosure and reconstruction of the existing exclosure fence.
Ash Spring; exclosure from FR9709P on the west side to the edge of the bench on the east side and 500 feet downstream. Pipe water to trough outside exclosure for livestock.
Vegetation Treatments for Wildfire Threat Reduction
Vegetation treatments have been proposed to mitigate fuels and reduce the threat of high intensity, high severity wildfire. This will assist in the protection and restoration of wildlife habitat and watershed functionality through a controlled reduction of accumulated fuels to an ecologically desirable level. These treatments would include the creation of openings in the juniper canopy across 7,977 acres around the communities of Cienega and Dugas, and a two-chain1 wide fuel break along FR732, from the intersection with FR68D east towards Squaw Peak to the project boundary. These treatments are shown on map 1 in appendix E. The primary treatment method will be to thin the juniper overstory with subsequent pile burning. Treatment prescriptions will follow wildlife needs for habitat improvement in the areas identified.
1 One chain equals 66 feet.
8 Verde Ranger District, Prescott National Forest
Dispersed Recreation
The proposed action includes actions to limit and mitigate soil compaction and vegetation loss in the riparian area from dispersed recreation use in the Yellow Jacket area in order to improve wildlife habitat and watershed functionality.
Access to the Yellow Jacket dispersed site would be limited to a single sustainable road entrance for passenger vehicles, including trucks with recreational trailers (horse or OHV). It would be reinforced with an aggregate base, and designed with appropriate drainage and barriers. Site boundaries would be delineated with boulders of adequate size to limit motorize travel and further site expansion.
An information kiosk would be installed along Dugas Road to provide visitors with policy and regulatory information and to display a map of recreation opportunities in the area.
The area immediately north of Yellow Jacket dispersed site, near FR9602R and FR9650W, would be evaluated and an appropriate area would be delineated with boulders or other engineering controls to limit expansion of existing dispersed sites.
Mesquite and Catclaw Treatment Alternative
The Mesquite and Catclaw Treatment Alternative would include all of the treatments and activities listed above in the Proposed Action plus the treatment of areas within the Agua Fria Grasslands where mesquite and catclaw is dominating the shrub component within TEUI 370 (Semi-Desert Grassland) ecological sites (map 3 – appendix E).
The objective would be to reduce mesquite and catclaw where it is determined to be adversely affecting the grassland plant community. In the Semi-Desert Grassland PNVT, mesquite and catclaw can outcompete herbaceous vegetation for water and nutrients, resulting in greatly reduced protective soil cover, increased surface runoff and erosion. The loss of herbaceous grasses and the closure of the open canopy conditions contribute to degradation in the quality of the habitat for pronghorn and other types of wildlife within the grasslands.
Mesquite typically doesn’t respond well to mechanical or fire control methods due to its deep, extensive root system and a budding zone in the roots which lies six inches below ground. These characteristics allow mesquite to re-sprout after cutting or burning. Catclaw acacia and mimosa are typically top-killed by fire but resprout following fire.
The goal of mesquite/catclaw treatment would not be eradication from the site, rather it would be to reduce mesquite/catclaw occurrence so that it fits within canopy values described by the TEUI potential and the desired conditions in the Forest Plan (DC-Veg-21). Treatment methods would include the use of herbicides triclopyr , clopyralid, and picloram with the surfactants and using a cut-stem application to prevent sprouting.
Herbicices are absorbed through the cambium layer of the stems and cut stumps and trans-located to the root system within the soil. There is very little risk to the general public from application of these herbicides to cut mesquite/catclaw stumps; the primary risk of human exposure is from
9 Agua Fria Grasslands Improvement Project workers handling the herbicide and conducting the application. This risk can be minimized through the establishment of proper herbicide handling and application protocols.
There are a total of 834 acres of TEUI 370 identified for the project area, however, it is expected that the number of acres treated will be less due to exclusion areas. These would include any identified Stream Management Zones (SMZs) within or adjacent to the proposed treatment area. The treatment area is estimated to be approximately 580 acres.
Alternatives Considered but Eliminated from Detailed Study
Two alternatives were considered, but dismissed from detailed consideration for reasons as summarized in the following paragraphs.
Alternative that facilitates prescribed burning: An alternative that gives broader discretion to the fuels program by changing the project mitigations was considered during the development of the proposed action. These proposed mitigations, which would have allowed for unlimited low soil burn severity treatments within sub-watersheds and doubled the allowable extent of moderate to high soil burn severity treatments, did not meet the purpose and need of the project.
Alternative that restores public access to the Marlowe Mesa area: An alternative that proposed approximately ½ mile of new road construction in order to secure improved access to FR9601R and the Marlowe Mesa area was also considered during the development of the proposed action. Currently, there is limited public access via motorized trail, however, this alternative would have facilitated management activities, improved public access, and supported Objective -30 (Identify and act on up to 10 opportunities to secure legal access to areas where historic access to the national forest has been lost) in the Forest Plan. It was dropped from further consideration by the District Ranger in response to landowner, livestock grazing permittee, and Central Arizona Grasslands concerns.
Environmental Impacts of the Proposed Action and Alternatives This section summarizes the potential impacts of the proposed action and the mesquite treatment alternative for each impacted resource. Resources that were not impacted and therefore not further analyzed include Lands, Minerals, and Special Uses.
Vegetation
This section summarizes the potential impacts of the proposed action and the mesquite treatment alternative on the potential natural vegetation types (PNVTs) found within the Agua Fria Grasslands analysis area. The full analyses can be found in the Agua Fria Grasslands Improvement Project Vegetation Specialist Report (Forest Service, 2014b) and the Agua Fria Grasslands Improvement Project Herbicide Application Analysis (Forest Service, 2014j).
10 Verde Ranger District, Prescott National Forest
Affected Environment
From largest to smallest the four upland PNVTs in the Agua Fria Grasslands Improvement project area are:
Piñon-Juniper Evergreen Shrub (47,832 acres)
Semi-Desert Grassland (27,449 acres)
Juniper Grassland (12,732 acres)
Interior Chaparral (7,903 acres)
In addition there are 1,405 acres of riparian and a token amount (484 acres, combined) of the two ponderosa pine PNVTs (see table 3). More in depth data on the existing condition of the vegetative types can be found in the Agua Fria Grasslands Vegetation Specialist Report
Table 3. Vegetation Types within the Agua Fria Project Area
Percent of Forest-wide Vegetation Type Project Acres Forest-wide acres acres in project area
Piñon-Juniper Evergreen Shrub 47,832 463,296 10.3%
Semi-Desert Grassland 27,449 125,712 21.8%
Juniper Grassland 12,732 137,274 9.3%
Interior Chaparral 7,903 315,445 2.5%
Riparian 1,405 12,439 11.3%
Ponderosa Pine2 484 118,591 0.4%
Totals 97,805 1,247,328 7.8%
Piñon-Juniper Evergreen Shrub
TEUI 430, 432, 446, 461, 462, 464, 466, 479, 485, 491
The Piñon-Juniper Evergreen Shrub PNVT, with an understory dominated by a mix of shrub species, generally occurs on elevated and lowland plains, hills, and lower mountain slopes. The soils associated with this PNVT are variable and include those derived from granite, limestone, basalt, sandstone, and alluvium.
It covers approximately 49 percent of the Aqua Fria analysis area. It arcs around the north and east sides, between the grasslands and the Verde Rim, with the densest stands found on either side of FR732 and extending across Arnold Mesa.
2 Ponderosa pine acres include those for both the Ponderosa Pine-Evergreen Oak PNVT and the Ponderosa Pine-Gambel Oak PNVT.
11 Agua Fria Grasslands Improvement Project
In the project area, it is represented by piñon and juniper trees on basalt soils between 4,400 and 6,400 feet in elevation on mostly moderate (15 to 40 percent) slopes. TEUI predicted and actual tree cover is similar, ranging from 12 percent (TEUI 432) to 27 percent (TEUI 462). Utah juniper (Juniperus osteosperma) is dominant between 4,000 and 5,000 feet in elevation, with alligator juniper (J. depeanna) the most common in higher elevations. Piñon pines include Arizona (Pinus fallax) and twin needle (P. edulis). TEUI 485 has alligator juniper and piñon pine while TEUI 491 has alligator juniper associated with Arizona white oak (Quercus arizonica).
TEUI predicts shrub cover of between 23 percent (TEUI 430) and 34 percent (TEUI 485); actual shrub cover averages 24 percent. Shrub live oak (Quercus turbinella) is the dominant shrub; other shrubs include desert ceanothus (Ceanothus greggii), catclaw mimosa (Mimosa acanthocarpa biuncifera) and mountain mahogany (Cercocarpus montanus). Predicted grass cover averages about 18 percent, with actual cover averaging about 21 percent. The most common species are sideoats grama (Bouteloua curtipendula) and curly mesquite (Hilaria belangeri), with blue (B. gracilis) and hairy gramas (B. hirsuta) also present on most units.
Within the project area, this PNVT shows actual tree and shrub cover similar to TEUI predicted, however, there is a low similarity to desired conditions for vegetation structure (Forest Plan, DC- Veg-7). The mid-scale assessment shows about 10,000 acres with greater than 30 percent canopy cover; this information was used to develop the proposed action. The within-group tree and shrub density is higher than desired, with too many young and mid-aged trees and shrubs growing closely together and a higher proportion of recently disturbed, open-canopy grass-forb-shrub state than expected. This is likely due to past fuelwood sales used to thin juniper in this PNVT and the Juniper Grassland near Grassy Mountain, Brushy Basin, Cedar Tank and Mill Point Tank. No sale areas have been offered since the early 1990s. Current fire frequency and severity show some similarity to desired conditions, with less than desired frequency of 35 to 100 years in some areas (although the Cave Creek fire in 2005 burned in some of the TEUI 430 and 432), but similar severity and intensity of fires when they do occur.
Semi – Desert Grassland
TEUI 370, 371, 372, 373
The Semi-Desert Grassland PNVT is found at elevations ranging from 3,000 to 4,500 feet. These grasslands are bounded by the Desert Communities PNVT at the lowest elevations and the Piñon- Juniper Woodlands or Interior Chaparral PNVTs at higher elevations. Species composition and dominance varies based on soils and topography. The more common grass species include black grama, blue grama, hairy grama, tobosa, and giant sacaton. Various shrubs species also inhabit these grasslands including: creosote bush, catclaw acacia, mimosa, burroweed, broom snakeweed, and mesquite.
Twenty eight percent of the Agua Fria analysis area is Semi-Desert Grassland, bounded on the west by Interstate 17 and the others sides by the Piñon-Juniper Evergreen Shrub and Juniper Grassland vegetation types. The majority (74 percent) of this PNVT is TEUI 372 (0 to 15 percent slope, deep silty clay loam); TEUI 373 (15 to 40 percent slope, shallow stony clay loam) makes
12 Verde Ranger District, Prescott National Forest up 23 percent. TEUI 370 (884 acres) is a deep, gravelly, sandy loam. This is important because the difference in soils is reflected in the diversity of the vegetative communities.
There is no tree cover in the Semi-Desert Grassland PNVT, and the average actual shrub cover is slightly lower than TEUI predicted by about one to six percent. The mid-scale assessment shows about 11,000 acres with greater than 10 percent canopy cover; this information was used to develop the proposed action. Grass cover on TEUI 372 (43 percent actual) is lower than predicted (51 percent), and higher (35 percent actual) than predicted (30 percent) on TEUI 373. Plant basal area is slightly less on TEUI 372 (15 to 20 predicted, 14 actual) and slightly more than predicted on TEUI 373 (10 predicted, 11.7 actual).
A drying trend began in 1996 and most years since 2001 have been below average for precipitation; four of the five driest years since 1984 have occurred during this period. This prolonged dry period will have slowed but not stopped establishment of new woody plants. The dominant plant on the semi-desert grasslands in tobosa grass (Plueraphis mutica). Other common grasses are vine mesquite (Panicum obtusum), sideoats grama, black grama (B. eriopeda), and curly mesquite.
Like other grasslands, the Semi-Desert Grassland is dependent on natural fire and in the absence of fire there is an increase in both shrub density and trees can encroach into the grassland. The amount and distribution of mesquite (Prosopsis velutina), catclaw mimosa, catclaw acacia (Acacia constricta), prickly pear (Opuntia spp.) and snakeweed (Gutierezzia sarothrae) is kept in check by fire. Shrubby buckwheat (Eriogonum wrightii) and yerba-de-pasmo (Baccharis pterinoides), both important wildlife forage species, increase with fire, as does grass cover (Brock, 1998). Studies found that fire to remove standing litter from previous year’s growth also increased production of tobosa grass. Fire is the natural means of reducing tobosa litter and controlling brush, and prescribed fire has been used successfully in the southwest for many years.
Prescribed fire was used in the Agua Fria analysis area regularly from 1981 through 2001 and then discontinued because of the effects of the drought on the grassland. Typical prescribed burns and most wildfires burn in a mosaic leaving a percentage of the area unburned. TEUI 372 and TEUI 373 have been treated with prescribed fire; in most areas more than once. The most recent prescribed burning was in 2001 after which the onset of drought caused the practice to be discontinued pending more suitable conditions. In 2005 the Butte Fire burned about 8,000 acres, the majority of which was TEUI 372. With the exception of a prescribed burn that caused grass mortality in the center of Yellowjacket Mesa, the effects of both prescribed and wildfire have been positive.
Across the forest, the Semi-Desert Grassland PNVT shows a low similarity to desired conditions for vegetation structure and fire disturbance. Within the project area, about 40 percent of the PNVT has greater than ten percent shrub canopy cover. Current conditions include an encroachment by woody vegetation, loss of perennial grass cover, and increases in exposed soil surfaces. Fire historically occurred every 2 to 10 years in the Semi-Desert Grassland PNVT, and the desired frequency in the forest plan is every 10 to 15 years. Current fire activity within the PNVT as a whole is considerably less often than desired, however the some of the Semi-Desert
13 Agua Fria Grasslands Improvement Project
Grassland within the project area burned in the Butte Fire in 2005, bringing it within the desired range for fire frequency.
Juniper Grassland
TEUI 427, 428, 431, 463, 490
The Juniper Grassland PNVT, with a grass and forb dominated understory and scattered overstory trees, generally occurs on flats, basins, gentle sloping foothills, and transitional valleys at generally lower elevations. The soils associated with juniper grasslands are generally deep and productive.
The Juniper Grassland PNVT comprises 13 percent of the Agua Fria analysis area. The majority (92 percent) of the PNVT is in three geographically separate TEUI map units: TEUI 427, TEUI 431 and TEUI 490. Most of TEUI 427 is north of the Dugas road and adjacent to either side of the Reimer road. TEUI 431 is found primarily south of Sycamore Creek from the forest boundary east toward 22 Mesa. TEUI 490 is located on Tule and Little Mesas with a small area on Arnold Mesa. TEUI 490 is above 5,000 feet in elevation and the dominant vegetation is alligator juniper with blue grama.
In TEUI 427, there is no difference between the TEUI predicted and measured cover for both trees and grass. Utah juniper is the dominant tree and tobosa is the dominant grass, while in years of favorable moisture, cane bluestem (Bothriochloa barbinodis) is common. Density for shrubby buckwheat (Eriogonum wrightii) and cactus, the most common shrubs, is TEUI predicted at 22 percent and measured at 16 percent.
In 2005 the Cave Creek Fire burned on the east side of FR677 from the southern forest boundary to Sycamore Creek. This affected TEUI 431; there are no measurements for actual tree canopy or shrub cover post-burn. Prior to the fire, both were below TEUI predicted by about 4 percent. The percent mortality has not been estimated; however, following a fire catclaw regenerates quickly and may have actually increased. Grass cover on TEUI 431 is about 10 percent below TEUI predicted. This unit has a diverse grass component, with sideoats and hairy gramas and curly mesquite dominant.
TEUI 490 is dominated by even aged, uniformly sized trees with residual stands of uneven aged trees, including monarch juniper and Arizona piñon pine. Herbaceous ground cover is reduced in the even aged stands but well represented in the residual stands and openings. The uniformity of the even age stands may be a result of livestock grazing removing light fuels that historically burned across the mesas. The TEUI predicted and actual tree density are similar at 28 percent, and the actual shrub cover is light, about 2 to 4 percent. TEUI predicted grass cover is about twice the 20 percent actual cover. The harvested openings have a greater shrub density from skunkbush (Rhus trilobata), mountain mahogany (Cercocarpus montanus) and some shrub live oak.
There is a history of commercial fuelwood sale blocks totaling several hundred acres in TEUI 490, and a number of small sales that harvested selected trees from the even aged stands to create more structural diversity. Both TEUI 431 and TEUI 427 have been successfully treated with
14 Verde Ranger District, Prescott National Forest prescribed fire to reduce the woody plant density. Mechanical thinning of juniper has also been implemented in the Reimer basin and at the north end of Reimer Ridge on the Cienega grazing allotment.
Existing conditions for the Juniper Grassland PNVT are moderately similar to desired ecological conditions. The desired fire frequency is every 1 to 35 years.
Interior Chaparral
TEUI 425, 436, 448, 457, 475, 476, 551
The Interior Chaparral PNVT occurs at mid-elevations (3,400 to 6,600 feet) on foothills and lower mountain slopes. It is bordered by ponderosa pine or piñon-juniper woodlands at the upper elevations, and semi-desert grasslands at the lower elevations. Interior chaparral has a uniform dense structure dominated by shrubs with thick, stiff, waxy evergreen leaves. Mixed shrub associations include: shrub live oak, manzanita, desert ceanothus, mountain mahogany, silktassles, Stansbury cliffrose, evergreen oaks, sumacs, and various cacti. Grasses are a minor component in chaparral and may include grama, threeawn, and muttongrass species.
Eight percent of the analysis area is Interior Chaparral PNVT. Most of the large drainages have chaparral on the side slopes above 4,500 feet, and dense stands are found in Brushy Basin along the north end of FR68D and the slopes above the FR68D and FR732 intersection. The largest, most diverse chaparral stands are associated with Piñon-Juniper Evergreen Shrub along the Prescott and Tonto National Forests boundary in the Silver Creek sub-watershed.
Shrub live oak is dominant in all map units; mountain mahogany and skunkbush are also present in most units. Pringle (Arctostaphylos pringeli) and pointleaf manzanita (A. pungens) can be found across TEUI 425, 448, 475 and 551. Alligator juniper occurs in TEUI 425, 457 and 551, with the latter also containing ponderosa pine (Pinus ponderosa) and Gambel oak (Quercus gambelii). Grasses vary from 4 percent (TEUI 551) to 14 percent TEUI 457) predicted and actual ranges from 4 percent (TEUI 448) to 17 percent (TEUI 551).
The vegetation composition, structure, and fire characteristics within the Interior Chaparral PNVT exhibit a high similarity to desired conditions.
Ponderosa Pine
TEUI 540, 560, 570
There are two ponderosa pine PNVTs classified for the Prescott NF: Ponderosa Pine-Evergreen Oak and Ponderosa Pine-Gambel Oak.
The Ponderosa Pine-Evergreen Oak PNVT generally occurs at elevations ranging from approximately 6,000 to 7,500 feet. These forests are dominated by ponderosa pine and can be distinguished from the Ponderosa Pine-Gambel Oak PNVT by one or more well represented evergreen oak species (e.g., Emory oak and Arizona white oak), juniper species, piñon pine species, and Arizona cypress in some locations. These forests have an understory of primarily
15 Agua Fria Grasslands Improvement Project evergreen shrubs including manzanita, turbinella oak, sumac species, and mountain mahogany species.
The Ponderosa Pine-Gambel Oak PNVT generally occurs at elevations ranging from 5,500 to 9,000 feet on hills, mountain slopes, and some elevated plains. These forests are dominated by ponderosa pine and Gambel oak and commonly include other tree species such as New Mexico locust, juniper, and piñon. Species such as aspen, Douglas-fir, and white fir may be present, especially in relatively moist areas. There is typically an understory of grasses and forbs with occasional shrubs.
In the project area, these two PNVTs are found on the north facing slope of Tank Canyon (TEUI 540) on slopes averaging 50 percent and in a small stand of TEUI 570 along the Verde Rim adjacent to the north boundary of the Pine Mountain Wilderness on 8 percent slope. Ponderosa pine is dominant in both map units; TEUI 540 also has Arizona white oak and Gambel oak, whereas Gambel oak and alligator juniper are the associated tree species in TEUI 570.
Riparian
TEUI 30, 34, 41, 42, 43, 50, 55
Riparian Gallery Forest PNVT occurs along perennial or intermittent streams ranging in elevation from 2,000 to 8,000 feet. It contains two major vegetation communities; cottonwood-willow and mixed broadleaf deciduous forests. The dominant woody vegetation varies in both composition and structure according to elevation, substrate, stream gradient, and depth to groundwater. Common species include Fremont cottonwood, narrowleaf, Gooding and Bebb willow, Arizona sycamore, velvet and green ash, Arizona alder, Arizona walnut, and box elder. On occasion it can also include various species of oak, pine, or juniper from adjacent uplands. Herbaceous plants include several forbs, sedges, rushes, and grasses.
TEUI 30 and TEUI 41 are riparian map units, whereas TEUI 34, TEUI 42 and TEUI 55 are out of the wetted zone and support upland vegetation. The Prescott Riparian Inventory and Monitoring Methodology (PRIMM) classifies TEUI 30 as a velvet ash (Fraxinus velutina)/Fremont cottonwood (Populus fremontii)/Gooding willow (Salix goodingii) community type and TEUI 41 as a velvet ash/ Arizona sycamore (Platanus wrightii)/ Fremont cottonwood type. The riparian map units were not sampled in the Ecological Inventory because they have a naturally high range of variability due to their susceptibility to flood impacts; however, the spatial and interpretive data is derived from the Regional Riparian Mapping Project (RMAP).
Environmental Consequences
Common to All Alternatives
Although both ponderosa pine PNVTs have a low similarity to desired conditions, no management actions for these PNVTs have been proposed within the project area under any of the alternatives. Due to their remote location, difficult terrain, and relative scarcity within the project area, it would be impractical to treat these TEUIs.
16 Verde Ranger District, Prescott National Forest
The Riparian TEUIs (30, 34, 41, 42, and 50) have been designated as fire avoidance areas and will not receive any direct treatment. It should be noted that fire may still move into these TEUIs from adjacent treatment areas, but the fire intensity and rate of spread, and thus the impacts, would be expected to be low.
No Action
Piñon-Juniper Evergreen Shrub
If the proposed treatments were not implemented, the closed state of the juniper canopy would be expected to increase or remain at current density, depending on the seral stage of the stands. This would inhibit herbaceous growth in the understory and maintain or increase the departure from the desired conditions for vegetation structure in this PNVT.
The piñon pine component of this vegetative type has been weakened by drought and the trees are susceptible to disease and insects; however, with increased precipitation, some recovery in the piñon population would be expected. Tree recruitment in stands previously harvested for fuelwood would eventually displace the shrubs and grasses released by the opening of the tree canopy if no additional treatments are applied to maintain an open state.
Semi-Desert Grassland
The Semi-Desert Grassland in the project area would continue to exhibit low similarity to desired conditions for vegetation structure if the proposed treatments were not implemented. The fire frequency would most likely continue to be infrequent without planned prescribed burns, and fire use would be limited to managed wildfire. This would lead to a departure from the desired fire frequency within the project area. Encroachment by woody species would continue to be a concern, as would higher than desired canopy percentages.
Juniper Grassland
Currently, conditions for the Juniper Grassland PNVT are moderately similar to desired ecological conditions; however they would trend away from similarity without the proposed actions to maintain them. The continued absence of fire contributes to an increased woody canopy and reduced re-growth and germination of fire-stimulated perennial grasses and forbs. These would not be immediate effects, rather the continuation of longer term trends.
Juniper thinning for the Pronghorn Corridor Habitat Improvement Project would continue for the foreseeable future; however, there would be no additional pronghorn habitat improvement or other mechanical treatments outside of its planned treatment areas.
Interior Chaparral
There would be few, if any, short term effects from not implementing the proposed action within the Interior Chaparral PNVT. Longer term, not implementing the proposed action would represent a lost opportunity to maintain desired conditions within this PNVT.
17 Agua Fria Grasslands Improvement Project
Proposed Action
Piñon-Juniper Evergreen Shrub
The proposed action to open the closed canopy to less than 30 percent on TEUI 432, 446, 461, 462, 464, 466, 485, and 491 would increase the shrub and herbaceous ground cover these map units and trend the PNVT towards desired conditions for vegetation structure and fire regime. The application of these treatments is supported by Objective -3 in the Forest Plan which directs the use of wildland fire to improve watershed and rangeland conditions, vegetation structure, and wildlife habitat in the Piñon-Juniper Evergreen Shrub PNVT.
These treatments would be of particular benefit to TEUI map units 446 and 462, where the herbaceous ground cover is below its potential and the ecological succession is between chaparral shrub species and piñon-juniper. Reduction of tree canopy in these units would result in a beneficial increase in shrub cover.
As noted in the description of the proposed action, 8,693 acres of fire treatment in TEUI 432, 462, 464, 485, and 491 would be designated as first priority due to multi-resource benefits; these include benefits to wildlife habitat through improved vegetation structure and increased forage, and watershed benefits such as reduced erosion potential and increased groundwater recharge through infiltration. Canopy reduction through fire would mostly benefit vegetation in TEUIs 446, 461, and 466 and thus they have been designated as second priority.
The majority of the treatments, on about 24,600 acres across all of the non-avoidance TEUIs, would maintain open-canopy conditions and trend the PNVT towards desired conditions. Two TEUIs, 430 and 479, have been designated as fire avoidance areas. Fire avoidance strives to limit fire effects on the soil and watershed by prohibiting direct ignition in these areas, however, fire is still allowed to move into these areas from adjacent burns. If kept within the project mitigation guidelines outlined in appendix A, the proposed treatments could be reasonably expected to have minimal to no short-term impact on the soil structure and watershed function. Further discussion can be found in the Soils and Watershed section.
Semi-Desert Grassland
The Semi-Desert Grassland PNVT shows low similarity to the desired conditions for vegetation structure described in the Forest Plan (DC-Veg-21). The proposed action would use prescribed fire, and managed wildfire when possible, to trend the grasslands toward desired conditions by reducing the canopy cover below ten percent and maintaining an open state through a restored fire return interval of approximately every 10 to 15 years. The desired fire return interval of 10 to 15 years could be overly long if maximum benefit is to be achieved in the map units with clay - loam soils. These treatments are supported by Objective -1 in the Forest Plan which directs the use of wildland fire to restore ecosystems conditions in the Semi-Desert Grassland PNVT.
The proposed treatments will span all four TEUIs (370, 371, 372, and 373) where needed. In TEUI 372 and 373, where shrub cover is light, the use of low intensity prescribed fire would maintain existing conditions and control seedlings and young shrubs, reducing encroachment. A
18 Verde Ranger District, Prescott National Forest moderate intensity fire would be used to induce woody species mortality where shrub cover is greater than the desired 10 percent.
In the past, the greatest woody plant mortality was achieved by timing burns when abundant annual forbs and grasses provided fuel and air temperatures were high; it is anticipated that these are the conditions under which the prescribed burns would be performed. Since 2001, there have been windows of opportunity to perform prescribed burns within the project area; however, there has not been any fire use within the project area in almost ten years. Vegetation and soil moisture conditions must be suitable for a successful fire treatment, and conditions on the ground can vary greatly based on the amount and timing of precipitation that an area receives. To facilitate the planning and implementation of fire treatments within the project area, the criteria for suitability for using fire as a management tool have been described in appendix D.
It is expected that fire intensity would be low due to the fuel types involved and that the soil burn severity would also be low and thus still within the bounds of the established project mitigations described in appendix A.
Juniper Grassland
The proposed actions for the Juniper Grassland PNVT include both mechanical treatments and the use of wildland fire for canopy reduction and open-canopy maintenance. The reintroduction of fire would move this moderately departed PNVT towards the desired conditions described in the Forest Plan (DC-Veg-6). These treatments are supported by Objective -3 in the Forest Plan which directs the use of mechanical treatments and wildland fire to improve watershed and rangeland conditions, vegetation structure, and wildlife habitat in the Juniper Grassland PNVT.
Per the proposed silvicultural prescription for this PNVT (appendix B), TEUI 490 would be reduced to less than 30 percent canopy closure using a combination of hand thinning and mechanical treatment. Fire could also be used when conditions are suitable. In the Juniper Grassland PNVT, research has found that woody plant mortality generally is greater the year following a fire than at the actual time of the burn due to damage to the cambium and phloem tissue in the tree trunk. The greatest potential to use fire in TEUI 490 is in areas of past fuelwood sales on Tule and Little Mesas and where thinning was done on Arnold Mesa. These same areas and existing natural opening could be expanded by hand thinning. Like the lower elevation juniper grasslands, TEUI 490 responds quickly to overstory reduction as the dominant grass is blue grama which can regenerate vegetatively and to a lesser extent from seed.
The Juniper Grassland PNVT has more herbaceous vegetation than the Piñon-Juniper Evergreen Shrub PNVT because of the lesser canopy cover. The herbaceous plants provide the fine fuels to kill seedlings and saplings and get the fire into the lower branches of the trees. Current canopy coverage in TEUI 431can be attributed to the effects of previous prescribe fires, the 2005 Cave Creek Fire, and a combination of hand thinning and mechanical treatments. The planned resumption of wildland fire treatments would further reduce or maintain tree canopy cover and increase herbaceous ground cover and composition; however, shrub cover may remain below predicted and near desired as a result of fire mortality on cactus. If kept within the project mitigation guidelines outlined in appendix A, the proposed wildland fire treatments could be
19 Agua Fria Grasslands Improvement Project reasonably expected to have minimal to no short-term impact on the soil structure and watershed function. Further discussion can be found in the Soils and Watershed section.
Healthy grasslands are important habitat for a variety of wildlife species and are essential to maintaining pronghorn antelope populations. In TEUI 427, a combination of hand thinning and mechanical treatments is proposed to remove vertical structure and reduce canopy cover to less than 5 percent. This would improve habitat quality for pronghorn on over 4,000 acres of Juniper Grassland adjacent to the Semi-Desert Grassland by creating a more desired open environment. This action is supported by Objective -26 in the Forest Plan, which direct the use of prescribed burning, mechanical tree removal, or other treatments to increase pronghorn antelope habitat quantity and quality in the grassland PNVTs.
Interior Chaparral
The Interior Chaparral PNVT within the analysis area is similar in plant composition, structure, and fire regime to the desired conditions described in the Forest Plan (DC-Veg-11). Treatments in interior chaparral are designed to maintain this fire-adapted system, with a fire frequency in any one location of once every 35 to 100 years.
The proposed action would maintain these vegetation conditions and fire regimes through fire treatments on 1,056 acres within TEUI 425 and 457. These map units are on slopes of 15 percent or greater, and the use of prescribed fire in them would have the effect of reducing the biomass of the treated stand and possibly killing trees growing within the stand. The spatial distribution of the chaparral would not change, but there would be a short term shift in composition favoring faster sprouting species such as catclaw, manzanita, and shrub live oak. This, in turn, would increase the forage value to wildlife with the greater palatability of new growth.
These treatments are supported by Objective -4 in the Forest Plan which directs the use of wildland fire maintain current conditions in the Interior Chaparral PNVT.
Mesquite Treatment Alternative
The Mesquite Treatment Alternative contains all of the same treatments and actions as the Proposed Action, with the addition of a proposal to use a cut-stump herbicide treatment to control mesquite encroachment on certain maps units in the Semi-Desert Grassland PNVT. Thus, the expected effects would be the same for both alternatives, with the exception of the additional effects associated with the mesquite treatment.
There are 834 acres of TEUI 370 in the unit identified for mesquite treatment, with approximately 580 acres targeted for application. The density of the mesquite in this unit varies from thickets near Ash Creek to scattered shrubs outside the floodplain. The grass cover is inverse to the shrub cover because of competition for water and from shading from the mesquite. Reducing the mesquite shrub density would increase herbaceous cover where shrub canopy is the limiting factor in grass establishment.
TEUI 370 is a complex of mostly coarse soil with a low water holding capacity that readily supports deeper rooted shrubs like mesquite. A cut-stump herbicide treatment was chosen to
20 Verde Ranger District, Prescott National Forest reduce the chance of the mesquite re-sprouting from its well-developed root system. Mechanical treatments alone can leave the below ground budding zone undisturbed, and broadcast burns have difficultly carrying across the unit when the herbaceous cover is as sparse as the current conditions. The herbicide treatment is expected to delay the reemergence of the mesquite long enough to allow the reestablishment of the desired herbaceous cover. Once reestablished, the grass cover would be sufficient to support wildland fire treatments to maintain the desired open canopy condition. The effectiveness of treatments would be monitored under an adaptive management strategy and adjusted as needed. This action is also supported by Objective -26 in the Forest Plan, which direct the use of prescribed burning, mechanical tree removal, or other treatments to increase pronghorn antelope habitat quantity and quality in the grassland PNVTs.
Cumulative Effects
Cumulative effects are “…the impact on the environment which results from the incremental impact of the action when added to other past, present and reasonable foreseeable future actions regardless of what agency (Federal or non-Federal) or person undertakes such other actions.” 40 CFR 1508.7
Past actions that contributed to existing conditions are prescribed fire and wildfire, hand thinning of juniper for habitat improvement, and fuelwood sales.
The prescribed burning program was active within the project area from 1980s through 2001. It contributed to current conditions by reducing shrub and tree cover, however the effects have diminished in the last decade. In 2005, the Butte Fire burned about 8,000 acres within the project area, the majority in the Semi-Desert Grassland PNVT. The low burn severity resulted in positive effects to the vegetation. The same year, the Cave Creek Fire Complex burned with some moderate to high burn severities in the Piñon-Juniper Evergreen Shrub and Interior Chaparral within the project area.
Thinning of juniper has been focused within an identified pronghorn travel corridor on the south end of the Prescott NF and the north portion of the Agua Fria National Monument (AFNM). The Pronghorn Corridor Habitat Improvement Project involves a total of about 5,800 acres and will continue for the foreseeable future. There is also an on-going effort to thin juniper with the Black Hills Vegetation Management Project on the Verde and Chino Valley Ranger Districts. These actions will continue for the foreseeable future with priority assigned to the Cienega Creek watershed.
Past fuelwood sales have occurred in the north end of the project area; the two most recent were in the early 1990s. The Grassy Mountain sale was an approximately 30 acre personal use sale in the Cienega Creek sub-watershed. The Tule Mesa sale was a small sale across about 100 acres in the Sycamore Creek sub-watershed. Both of these sales likely contributed to the current departed conditions for vegetation structure as there were no fire use or mechanical treatments to maintain open conditions after the sales.
The proposed action allows management of wildfires for reduction in overstory vegetation in all plant communities except riparian. This is consistent with the policy of the Bureau of Land
21 Agua Fria Grasslands Improvement Project
Management in the Agua Fria National Monument within the grassland ecosystem. Stream Management Zones and limitations on the percent of a watershed that can be burned with high- moderate burn severity are described to buffer the effects of fire on riparian ecosystems, water quality and soils. These mitigations (appendix A) also minimize the potential amount of adverse impact on vegetation if post burn precipitation is insufficient for regeneration.
Wildlife
This section summarizes the potential impacts of the proposed action and the mesquite treatment alternative on terrestrial, riparian, and aquatic wildlife and rare plants in the Agua Fria Grasslands analysis area. The full analyses can be found in the Agua Fria Grasslands Improvement Project Wildlife, Fish, and Rare Plants Specialist Report (Forest Service, 2014c).
Background
The following direction pertains to Terrestrial and Aquatic Wildlife Management.
Endangered Species Act
The ESA § 7(d) requires that Federal agencies “shall not make any irreversible or irretrievable commitment of resources with respect to the agency action which has the effect of foreclosing the formulation or implementation of any reasonable and prudent alternative measures which would not violate subsection (a)(2).” This project will not make irreversible or irretrievable commitments and the status quo will be maintained during the consultation process.
Southwestern Region Regional Forester’s Sensitive Species
The Regional Forester’s sensitive species program is the Forest Service’s dedicated initiative to conserve and recover plant and animal species according to Agency policy found at Forest Service Manual (FSM) 2670. Sensitive species are those plant and animal species identified by the regional forester for which population viability is a concern, as evidenced by: (a) significant current or predicted downward trends in population numbers or density or (b) significant current or predicted downward trends in habitat capability that would reduce the existing distribution of a species.
Management Indicator Species
The Forest Service is required to address Management Indicator Species (MIS) in compliance with the direction in the 1982 planning regulations. The 2015 Forest Plan was prepared under the 1982 planning regulations.. Effects to MIS were considered for this project and are documented in this report.
Bald & Golden Eagle Protection Act
The purpose of this assessment is to document if there is “take of eagles” with the proposed action, the No Action, or other action alternatives on bald and golden eagles protected under the
22 Verde Ranger District, Prescott National Forest
Bald and Golden Eagle Protection Act (B&GEPA). In the B&GEPA “take” is defined to include “pursue, shoot, shoot at, poison, wound, kill, capture, trap, collect, or molest or disturb.” The USDA Fish and Wildlife Service (FWS) subsequently defined “disturb” as follows: “Disturb means to agitate or bother a bald eagle or golden eagle to a degree that causes, or is likely to cause, based on the best scientific information available, (1) injury to an eagle, (2) a decrease in its productivity, by substantially interfering with normal breeding, feeding, or sheltering behavior, or (3) nest abandonment, by substantially interfering with normal breeding, feeding, or sheltering behavior.” (Federal Register Vol.72/No.107/page31132 June 5, 2007)
Migratory Bird Treaty Act (Executive Order 13186)
Under the Migratory Bird Treaty Act (MBTA), the Forest Service is required to address the effects of agency actions and plans on migratory birds and identify where unintentional take reasonably attributable to agency action is having, or is likely to have, a measurable negative effect on migratory bird populations. Effects to migratory birds were considered for this project and are documented in this report.
Affected Environment
Federally listed and Regionally Sensitive species or their habitats known in the Agua Fria Grasslands Improvement Project area or potentially affected by actions in the project area are listed below in table 4. See the Wildlife, Fish, and Rare Plants Specialist Report for the complete lists of these species for the Prescott NF.
Table 4. TE&S Species occurrences in the Agua Fria Assessment Area.
Federal Critical Common Name Scientific Name Status Habitat
Gila chub Gila intermedia Endangered Yes
Northern Mexican Thamnophis eques megalops Threatened Proposed gartersnake
Western yellow-billed Coccyzus americanus Threatened cuckoo occidentalis Proposed
Desert sucker Catastomus clarki Sensitive N/A
Lowland leopard frog Lithobates (Rana) yavapaiensis Sensitive N/A
Verde Rim springsnail Pyrgulopsis glandulosa Sensitive N/A
Pale Townsend big-eared Corynorhinus townsendii Sensitive N/A bat pallescens
23 Agua Fria Grasslands Improvement Project
Federal Critical Common Name Scientific Name Status Habitat
Western red bat Lasiurus blossevillii Sensitive N/A
Eastwood alum root Heuchera eastwoodiae Sensitive N/A
Tonto Basin agave Agave delamateri Sensitive N/A
Federally Listed
Gila chub
The Gila chub was listed as Endangered with Critical Habitat (CH) in 2005, and the development of a Recovery Plan for the species is in progress. Gila chub are known to occur in Sycamore, Little Sycamore, and Indian creeks in the Agua Fria River drainage. All three streams have been designated critical habitat for Gila chub and are characterized by perennial-interrupted flow (areas of perennial water separated by dry reaches of stream), thus provide less occupied habitat than available on the forest. In addition, designated CH for Silver Creek is present below the project boundary. The lateral extent of CH for each stream reach is 300 feet on either side of the stream channel.
Rangewide, the major threats to Gila chub include predation by and competition with non-native aquatic species and habitat alteration, destruction, and fragmentation. Because the species exists in small, isolated populations, they are highly susceptible to threats such as drought, flood events, and wildfire.
There is limited direct impact to occupied habitat of Gila chub from current management activities in the project area because of exclosures around occupied sites or rough terrain that restricts access to the stream. The species distribution and abundance are negatively impacted due to the presence of non-native aquatic species which are predatory and/or competitive with the chub. Impacts associated with the 2005 Cave Creek Complex wildfire have also reduced Gila chub habitat quantity and quality through excess sedimentation filling in pool habitats.
Northern Mexican gartersnake
The Northern Mexican gartersnake was listed as Threatened in 2014. Critical Habitat was proposed to be designated in 2013. Historically, this species is known from along Little Ash Creek on the forest. Populations in the Agua Fria River drainage which include Little Ash Creek are considered likely not viable as they are not reliably found with minimal or moderate effort and threats from harmful nonnative species are present .Proposed critical habitat within and downstream of the project area include 957 acres along 6.7 miles of Little Ash Creek from the confluence of Ash Creek upstream to its confluence with Yellow Jacket/Horner Gulch. The upper 3 miles occur on the Prescott NF in the project area. The lateral extent of proposed critical habitat is 600 feet on either side of bankfull stage.
24 Verde Ranger District, Prescott National Forest
Direct predation by non-native bullfrogs, crayfish, and fishes on Northern Mexican gartersnakes is a significant threat, as is predation on and competition with gartersnake prey species by these same groups of non-native taxa. Non-native fish, crayfish, and bullfrogs have reduced native populations of prey species throughout the range.
Rangewide, threats to the riparian and aquatic habitats of the Northern Mexican gartersnake include water diversions, groundwater pumping, dams, channelization, and erosion related effects. These factors can reduce the amount of water within occupied habitat, directly affecting its suitability for Northern Mexican gartersnakes. Other threats that alter the riparian vegetation such as development, road construction, flood control and water diversion, improper livestock grazing, high-intensity wildfire, and recreation use, can reduce the habitat’s suitability as cover for protection from predators, as a foraging area, and as an effective thermoregulatory site.
The main impacts to proposed critical habitat of Northern Mexican gartersnake in the project area are from high dispersed recreation use at two areas along Little Ash Creek and roads within and adjacent to pCH that are a source of impacts to soil, vegetation, and water quality.
Western yellow-billed cuckoo
The western distinct population segment of the yellow-billed cuckoo (YBC) was listed as Threatened in 2014. Critical Habitat was also proposed to be designated in 2014. On the Prescott NF, YBC have been documented along the Verde River, Sycamore Creek, and Little Sycamore Creek. Proposed critical habitat within the project area includes portions of Ash Creek, Little Ash Creek, Sycamore Creek, and Indian Creek The main impacts to YBC and their habitat in the project area are from high dispersed recreation use at two areas along Little Ash Creek and some recreation use and roads/trails within habitat along Sycamore Creek that are a source of disturbance and impacts to riparian vegetation.
Regionally Sensitive Species
Desert sucker
The desert sucker is listed as a Forest Service Region 3 sensitive species. Desert sucker occurrence in the project area includes Indian Creek, Sycamore Creek, Little Sycamore Creek, and Little Ash Creek. Threats to the species include the alteration of habitat from human activities and the presence of invasive aquatic species, such as non-native fish and crayfish, which are predatory or competitive with desert sucker.
Lowland leopard frog
The lowland leopard frog is listed as a Forest Service Region 3 sensitive species. The species occurrence in the project area includes Indian Creek, Sycamore Creek, Little Sycamore Creek, Little Ash Creek, and Cienega Creek. Threats to the species include habitat alteration and the presence of invasive aquatic species, such as non-native fishes, crayfish, and bullfrogs that are predatory or competitive with lowland leopard frog.
25 Agua Fria Grasslands Improvement Project
Verde Rim springsnail
The Verde Rim springsnail is listed as a Forest Service Region 3 sensitive species. The total range of this species is the Nelson Place Spring complex that forms the headwaters of Sycamore Creek. The spring occurs on private land and the area is used for livestock grazing. Threats include a highly restricted distribution with associated potential for extinction due to chance events, wildfire, improper livestock grazing, and recreational activities. A site visit in September 2010 revealed a large, healthy population at the main spring.
Pale Townsend’s big-eared bat
In Arizona, pale Townsend’s big-eared bat is widespread. Suitable habitat consists of steep, sheer cliffs and ledges to caves and mines. The population trends are thought to be declining due to loss of historic habitat of caves and mines.
This species appears to be relatively common at suitable roosting sites on the Prescott NF. Abandoned mines used by Townsend’s big-eared bats occur on all three Ranger Districts with the majority of them on the Bradshaw RD. There are several areas of steep slopes greater than 65 percent selected to represent cliffs and ledges that occur in the project area.
Western red bat
The Western red bat is associated with broad-leaf deciduous riparian forests. It is usually solitary, roosting primarily in the foliage of trees or shrubs; however, they have also been known to “roost” in leaf litter in the riparian zone. The loss of dense, mature cottonwood forest is a factor in declining abundance. In the project area, suitable habitat occurs along Cienega Creek, Little Ash Creek, Dry Creek, Little Sycamore Creek, and Sycamore Creek.
Eastwood alum root
This plant species is endemic to central Arizona within Coconino, Yavapai, Maricopa, and Gila counties. It can be found on moist shaded slopes in ponderosa pine forests and canyons at elevations from 3,480 to 7,874 feet. One population of alum root has been documented in the project area within the Sycamore Creek drainage.
Tonto Basin agave
The total range of Tonto Basin agave spans a small geographic area in Central Arizona. The greatest concentration of sites occurs near the northwest end of Roosevelt Reservoir in an area referred to as Tonto Basin, situated between the Sierra Ancha and Mazatzal Mountains. A couple of sites are known north of the project area in the Verde Valley. It is usually found atop benches (often high benches), at edges of slopes, and on open hilly slopes in desert scrub, overlooking major drainages and perennial streams, from about 2,350 to 5,100 feet elevation. It is also occasionally found in chaparral or juniper-grassland. Found in direct or indirect association with archaeological features. Plant surveys in the project area found suspected plant clones in the Indian Creek area.
26 Verde Ranger District, Prescott National Forest
Management Indicator Species
This project analysis assesses the impacts of this project to Management Indicator Species habitat quantity and quality within the project area and effects to forest-wide MIS habitat and population trends. The MIS and their habitat known to occur within the project area include the pronghorn and aquatic macro-invertebrates. Northern goshawk habitat occurs in the project area, but there are no proposed management actions in their habitat within the Ponderosa Pine PNVTs.
Aquatic macro-invertebrates
Aquatic macro-invertebrate MIS habitat can include both perennial and perennial interrupted streams. Sycamore Creek and Little Ash Creek have the greatest amount of perennial water and habitat for macro-invertebrates in the project area. There is limited perennial water in other streams within the project area, with most occurring near spring sites.
Poor water quality is a major threat to macro-invertebrates. Arizona Department of Environmental Quality ratings for Sycamore Creek and Little Ash Creek are inconclusive due to lack of sampling data, however, there were exceedances for E. coli for Little Ash Creek and no exceedances for Sycamore Creek for the last reporting period. The main land uses in the sub- watersheds that could affect water quality include livestock grazing and recreation (e.g. dispersed camping, hunting, and off-highway vehicle travel).
Pronghorn
Pronghorn MIS habitat within the project area includes both the Semi-Desert Grassland and Juniper Grassland PNVTs where tree and shrub cover is less than 10 percent. As noted in the Vegetation section of this report, The Semi-Desert Grassland has low similarity to the desired conditions for vegetation structure and fire disturbance described in the Forest Plan. The Juniper Grassland has a moderate similarity to vegetation structure and fire disturbance.
The total amount of Semi-Desert Grassland in the project area is 27,439 acres. About 11,000 acres have a greater than 10 percent canopy cover of shrubs and trees, indicating a departure from desired conditions. There are 12,733 acres of Juniper Grassland PNVT in the project area; a total of 4,149 acres is identified as suitable for pronghorn habitat based on its proximity to the Semi- Desert Grassland PNVT.
Northern goshawk
There are only 484 acres of Northern goshawk indicator habitat (Ponderosa Pine) in the project area and there are no goshawk observations for the area.
Bald and Golden Eagles
Bald eagle
Bald eagles typically nest within 1 mile of water along coasts, inland lakes, and rivers. The diet is mainly fish. In Arizona, nests are common on cliff ledges, rock pinnacles, and in cottonwood
27 Agua Fria Grasslands Improvement Project trees. In Arizona, a small resident population of approximately 40 pairs nests primarily along the Salt and Verde Rivers. There are nesting sites on the forest at Lynx Lake and along the Verde River, however, there is no suitable nesting habitat within the project area.
Golden eagle
Golden eagles can be found from the tundra, through grasslands, forested habitat and woodlands, south to arid deserts. They are aerial predators that eat reptiles, birds, and mammals, and will also scavenge carrion. Nests are built on cliffs or in the largest trees of forested stands that often afford an unobstructed view of the surrounding habitat.
Within the Prescott NF, the Arizona Game and Fish Department Heritage Database Management System (HDMS) shows several locations for the species along the Verde River and one location in the vicinity of Woodchute Mountain. One nesting site is known within the project area. Suitable habitat occurs on cliff areas (greater than 65 percent slopes). Golden eagles also occur on the adjacent Agua Fria National Monument.
Migratory Bird Species
Sixty species of migratory birds are expected to occur or could potentially occur within the various PNVTs or habitat features associated with the Prescott NF. Of those sixty, the species listed below might be reasonably expected to occur within the project area based on the vegetation types.
Piñon-Juniper
Bird species commonly associated with piñon-juniper include the black-chinned sparrow, canyon towhee, gray flycatcher, pinyon jay, gray vireo, and black-throated gray warbler. Threats to these species include habitat changes, increased density of trees in the cover type, and reduced ground cover and shrub regeneration.
Semi-Desert Grassland
Bird species commonly associated with semi-desert grassland include the Cassin’s sparrow, grasshopper sparrow, and Swainson’s hawk. Threats to these species include unmanaged livestock grazing and the lack of fire disturbance resulting in increased density of shrubs and reduced ground cover.
Chaparral
Bird species commonly associated with chaparral include the black-chinned sparrow, black- throated gray warbler, canyon towhee, and Virginia’s warbler. Threats to these species include lack of fire disturbance in portion of vegetation type, and high percent of closed canopy.
28 Verde Ranger District, Prescott National Forest
Riparian Areas
Bird species commonly associated with riparian areas include the Lawrence’s goldfinch, MacGillivray’s warbler, red-faced warbler, Bell’s vireo, yellow warbler (Sonorana ssp.), and common black hawk. Threats to these species include habitat alteration or loss, water diversions near private lands and potential housing developments, human disturbance, and impacts to riparian vegetation near high use dispersed recreation areas.
Ponderosa Pine
Bird species commonly associated with ponderosa pine include the olive-sided flycatcher, Cordilleran flycatcher, purple martin, flammulated owl, Grace’s warbler, olive warbler, and red- faced warbler. Threats to these species include lack of fire disturbance resulting in increased density of trees and reduced ground cover, and stand-replacing wildfire.
Desert Scrub
Bird species commonly associated with desert scrub include sage thrasher, sage sparrow, Brewer’s sparrow, and purple martin. Threats to these species include habitat loss, exotic vegetation, and uncharacteristic fire.
Environmental Consequences
No Action
There would be no actions taken under this alternative, so there would be no direct effects to species or their habitat in the project area from project activities. There would also be no direct effects to primary constituent elements (PCEs) of critical habitats for Federally listed species.
It was determined that the No Action alternative would have no effect on Federally listed or Regionally sensitive species or their critical habitat and that it would not be likely to result in a trend toward Federal listing.
Sub-watershed condition impairments related to soils, upland and riparian vegetation, roads, and fire regime would remain and would continue to impair watershed function. These impairments affect the water quality, quantity, and timing of water delivery downstream, and failure to address impairments across the landscape of the project area could result in reduced water quality (PCE- 3) and effects to macro-invertebrate populations (food items for prey species) (PCE-4) in species habitat. The lack of proposed treatments to improve watershed conditions would have an indirect negative impact on wildlife and their habitats within the project area.
Proposed Action and Mesquite Alternative
The analysis of effects to species and their habitat evaluates direct, indirect, and cumulative effects for the proposed action and the mesquite treatment alternative. Both alternatives would implement best management practices (BMPs), streamside management zones (SMZs), and recommended treatment limitations that stipulate the amount of watershed area that can be treated
29 Agua Fria Grasslands Improvement Project with prescribed fire in the project period (see appendix A). The environmental consequences for both alternatives are similar in extent, duration, and magnitude and therefore are grouped together for analysis. For those species with designated critical habitat, the effects analysis approach in the Wildlife, Fish, and Rare Plants Specialist Report identified how the primary constituent elements essential to the conservation of the species are likely to be affected by the proposed actions.
Federally Listed
Gila chub
It was determined that either alternative (proposed action or mesquite treatment) may affect, but are not likely to adversely affect Gila chub or Gila chub critical habitat.
Wildland fire would occur in all Gila chub sub-watersheds and would cause short-term increases in runoff, sediment, and ash to drainages during post-fire precipitation events, however, there would be no direct effects to the species or critical habitat because there are no direct ignitions or vegetation treatments within the 300-foot lateral extent on either side of critical habitat along Sycamore, Little Sycamore, and Indian Creeks. The magnitude of effects is based on factors such as the amount of area burned, fire severity, slopes, and post fire precipitation intensity. The duration of increased sediment yields from treated areas is generally two to seven years and varies based on the rate of reestablishment for vegetative ground cover and litter.
The indirect effects of sediment yield to species habitat in Little Sycamore, Sycamore, and Indian Creeks from fire treatments in the sub-watersheds would be mitigated by a 300-foot SMZ along each of the streams, a 150-foot SMZ along USGS National Hydrography Database (NHD) mapped streams and mapped riparian areas, fire avoidance areas on steep slopes, and limits on the percent of each sub-watershed treated with fire based on soil burn severity. These mitigations are outlined in appendix A. Overall, projects in the uplands would improve or maintain soils, vegetation, and fire regimes in the sub-watersheds with beneficial effects to water quality.
Mechanical or hand thinning of juniper within the Juniper Grasslands (TEUI 427 and 490) would occur in all Gila chub sub-watersheds, as would vegetation treatments for fuels reduction near Dugas. These treatments would cause temporary soil disturbance from mechanical equipment and longer-term reduction in tree canopy cover. The indirect effects to species and habitat would be mitigated by SMZs and applying BMPs. Overall, treatments would improve soil and vegetation conditions in the sub-watershed.
Road decommissioning and use restrictions would occur in all Gila chub sub-watersheds. One road, FR9601C, within species habitat is already closed off with barriers and no further action would be taken except for administrative removal from the Prescott NF Motor Vehicle Use Map (MVUM). The decommissioning of roads would be accompanied by temporary soil disturbance from mechanical equipment. Road use restrictions would reduce user impacts to roads and from off-road travel. Indirect effects to species and habitat would be mitigated by implementation of BMPs and the Watershed, Aquatic Wildlife, and Recreation, Transportation, and Facilities standards and guidelines described in the Forest Plan. Overall, the closing or restriction of roads
30 Verde Ranger District, Prescott National Forest would improve soil and vegetation conditions along the old road beds and reduce erosion, sedimentation, and soil compaction along restricted roads.
Fuels reduction treatments and the fuelbreak near Cienega Creek, spring improvement projects at Ash and Reimer Springs, dispersed recreation actions at and near Yellow Jacket, and the proposed mesquite treatment alternative would all occur outside of Gila chub sub-watershed and would have no effects on either the species or the habitat.
Overall, projects in the uplands would improve or maintain soils, vegetation, and fire regimes in the sub-watersheds with beneficial effects to water quality and healthy macro-invertebrate populations in the streams.
Northern Mexican gartersnake
It was determined that both alternatives (proposed action or mesquite treatment) may affect, but are not likely to adversely affect northern Mexican gartersnake or its proposed critical habitat.
There are no expected direct effects to northern Mexican gartersnake or its proposed critical habitat s there are no direct ignitions or mechanical treatments in the SMZs along Little Ash Creek.
Wildland fire in the Little Ash Creek sub-watershed would cause short-term increases in runoff, erosion, and sedimentation to drainages during post-fire precipitation events. The magnitude of these effects is based on factors such as the amount of area burned, fire severity, slopes, and post fire precipitation intensity. The duration of increased sediment yields is generally two to seven years and varies based on the rate of reestablishment for vegetative ground cover and litter.
The indirect effects of sediment yield to northern Mexican gartersnake habitat from fire treatments in the sub watershed would be mitigated by a 300-foot SMZs along Little Ash Creek, a 150-foot SMZs along NHD mapped streams and mapped riparian areas, fire avoidance areas on steep slopes, and limits on the percent of the sub-watershed treated with fire based on soil burn severity. These mitigations are outlined in appendix A.
Mechanical or hand thinning of juniper within the Juniper Grasslands (TEUI 427 and 490) would occur in the sub-watershed. These treatments would cause temporary soil disturbance from mechanical equipment and longer-term reduction in tree canopy cover. The indirect effects to northern Mexican gartersnake habitat would be mitigated by SMZs and applying BMPs. Overall, treatments would improve soil and vegetation conditions in the sub-watershed.
Road decommissioning and road armoring would occur near northern Mexican gartersnake habitat. The closing of roads and road armoring would be accompanied by temporary soil disturbance from mechanical equipment. Indirect effects to species and habitat would be mitigated by implementation of BMPs and the Watershed, Aquatic Wildlife, and Recreation, Transportation, and Facilities standards and guidelines described in the Forest Plan. Overall, the closing and armoring of roads would improve soil and vegetation conditions along the old road beds and reduce erosion, sedimentation, and soil compaction along armored roads.
31 Agua Fria Grasslands Improvement Project
Fuels reduction treatments near Dugas and Cienega Creek, the fuelbreak near Cienega Creek, and the proposed mesquite treatment alternative would all occur outside of the Little Ash Creek sub- watershed and would have no effects on northern Mexican gartersnake or its proposed critical habitat.
The spring improvement projects at Ash and Reimer Springs occur outside of species habitat and would have no effects to northern Mexican gartersnake. The dispersed recreation actions at Yellow Jacket occur near suitable/ occupied habitat and within the lateral extent of proposed critical habitat. There is potential for species disturbance during the short time period of project implementation.The proposal to provide a single armored road access and to delineate site boundaries in the Yellow Jacket area on Little Ash Creek would reduce impacts to aquatic/riparian habitat and to soils and vegetation of terrestrial space for northern Mexican gartersnake proposed critical habitat.
Overall, projects in the uplands would improve or maintain soils, vegetation, and fire regimes in the sub watershed with beneficial effects to water quality and healthy macro-invertebrate population in the streams to support native amphibian and fish prey species.
Western yellow-billed cuckoo
It was determined that both alternatives (proposed action or mesquite treatment) may affect, but are not likely to adversely affect Western yellow-billed cuckoo or its proposed critical habitat.
There are no expected direct effects to Western yellow-billed cuckoo or its proposed critical habitat because there are no direct ignitions or mechanical treatments within their suitable or occupied habitat.
The dispersed recreation actions at Yellow Jacket occur near Western yellow-billed cuckoo suitable or occupied habitat, as do some of the proposed road actions (decommissioning and armoring). With the project mitigations to reduce heavy equipment noise and disturbance during the nesting season (June to August), the proposed actions would have no effects to the species.
Wildland fire in the project area during the summer could cause short-term effects from smoke during the Western yellow-billed cuckoo nesting season. These effects would be mitigated by a 300-foot SMZ along suitable and occupied habitat; and a 150-foot SMZ along NHD mapped streams and mapped riparian areas. These mitigations are outlined in appendix A.
Fuels reduction treatments near Dugas and Cienega Creek, the fuelbreak near Cienega Creek, spring improvement projects at Ash and Reimer Springs, and the proposed mesquite treatment alternative would all occur outside of suitable or occupied habitat and would have no effects on Western yellow-billed cuckoo.
32 Verde Ranger District, Prescott National Forest
Regionally Sensitive Species
Desert sucker
It was determined that both alternatives (proposed action or mesquite treatment) may impact individuals or their habitat, but are not likely to result in a trend toward Federal listing of desert sucker. The analysis area includes the Little Ash, Little Sycamore, Sycamore, and Indian Creek sub-watersheds, and the effects would be similar to those described for the Gila chub
Lowland leopard frog
It was determined that both alternatives (proposed action or mesquite treatment) may impact individuals or their habitat, but are not likely to result in a trend toward Federal listing of lowland leopard frog. The analysis area includes the Cienega, Little Ash, Little Sycamore, Sycamore, and Indian Creek sub-watersheds, and the effects would be similar to those described for the Gila chub
Verde Rim springsnail
It was determined that neither alternative (proposed action or mesquite treatment) would have an effect on the Verde Rim springsnail. There are no direct effects to the species because there are no fire or vegetation treatments in its occupied habitat.
Pale Townsend’s big-eared bat
It was determined that neither alternative (proposed action or mesquite treatment) would have an effect on the pale Townsend’s big-eared bat. There are no direct effects to the species because there are no fire or mechanical treatments proposed within its suitable or occupied habitat.
Western red bat
It was determined that neither alternative (proposed action or mesquite treatment) would have an effect on the western red bat. There are no direct effects to the species because there are no fire or vegetation treatments in its suitable or occupied habitat.
Eastwood alum root
It was determined that neither alternative (proposed action or mesquite treatment) would have an effect on the eastwood alum root. There are no direct effects to the species because there are no fire or vegetation treatments in its suitable or occupied habitat.
Tonto Basin agave
It was determined that neither alternative (proposed action or mesquite treatment) would have an effect on the Tonto Basin agave. There are no direct effects to the species because there are no fire or vegetation treatments in its occupied habitat.
33 Agua Fria Grasslands Improvement Project
Management Indicator Species
This section describes the impacts of this project on Management Indicator Species habitat quantity and quality within the project area, and the effects to forest-wide MIS habitat and population trends. The MIS and their habitat known to occur within the project area include the pronghorn and aquatic macro-invertebrates. Northern goshawk habitat occurs in the project area, but there are no proposed management actions in their habitat, as it is within the ponderosa pine vegetation types.
Aquatic macro-invertebrates
There are no expected changes in aquatic habitat quantity or quality, as there are no actions proposed within aquatic habitats in the project area. There is no expected increase in water yield or reduction in water quality from wildland fire as treatments would adhere to the project mitigations described in appendix A. Other management actions would be limited in extent and would not affect water quantity or quality in the treated areas, when BMPs are implemented and Forest Plan standards and guidelines are followed. .
Overall, management actions would improve watershed condition indicators related to roads, soils, fire regime, and rangeland vegetation that collectively would maintain or improve water quality for macro-invertebrates.
Pronghorn
Under the Proposed Action, there would be no vegetation type conversion of grassland habitats using wildland fire and/or vegetation treatments. Pronghorn habitat could be reasonably expected to increase in quantity by about 47 acres and improve in quality on an additional 2, 280 acres due to the decommissioning of nine and a half miles of road within Grassland PNVTs in the project area.
Grassland habitat quality would be maintained or improved on 27,439 of Semi-Desert Grassland and on 4,149 acres of Juniper Grassland that have been identified as pronghorn MIS indicator habitat. Overall, the proposed action or the mesquite treatment alternative would maintain or improve about 16 percent (31,588 acres) of the pronghorn habitat on the Prescott NF. This would alter current forestwide trends with improvement in habitat quality which should result in an increase in population.
Northern goshawk
There are no treatments proposed in the Ponderosa Pine PNVTs, so there would be no effect to Northern goshawk from the proposed action or the mesquite alternative.
34 Verde Ranger District, Prescott National Forest
Bald and Golden Eagles
Bald eagle
Since no bald eagle nests or suitable habitat exists within the project area, implementing the proposed action or the mesquite alternative would not result in take of bald eagles or habitat.
Golden eagle
Suitable nesting habitat exists on steep cliffs in the project area. There are no expected direct effects since fire is unlikely to burn into cliff habitats. Possible short-term effects (measured in days) from smoke dispersing into nesting habitat would not affect reproduction or nesting success. Regular fire helps to keep foraging habitat in a suitable condition for many prey species and increases hunting efficiency. Implementing the proposed action or the mesquite alternative would not result in take of golden eagles or habitat.
Migratory Bird Species
Effects to migratory birds are grouped by changes to conditions within each PNVT, impacts to habitat features, and potential for impacts from activities. Moving toward desired conditions for PNVTs that reflect reference conditions would provide habitat components for all migratory bird species on a landscape basis. Snag retention would be compliant with the forest plan direction in this project. Removal and/or destruction of vegetation used by migratory birds is NOT a taking under the MBTA.
The majority of impacts to migratory bird habitat would be from wildland fire and vegetation treatments in the project area. The main PNVTs to be treated include the Piñon-Juniper Evergreen Shrub, Semi-Desert Grassland, and Juniper Grassland. Wildland fire and vegetation treatments would occur incrementally across the project area to reduce impacts to sub-watershed conditions. Wildland fire is most likely to occur during the monsoon period (June to October) for both natural and prescribed fire. This is usually after the nesting season for most migratory birds. Fire treatments would have short-term effects to habitat for migratory bird species. In most cases, herbaceous and shrub canopy cover is back to pre-fire conditions in 5 to 7 years. In addition, wildland fire would result in a mosaic of burned and unburned areas in the treatment area. Vegetation treatments could occur throughout the year though it is less likely to occur during hot temperatures in the summer months. Long-term benefits to migratory birds would be the improvement in similarity to the desired conditions described in the Forest Plan. This would maintain or improve the composition, structure, and juxtaposition of migratory bird habitats in the project area.
The other management actions related to the transportation system, riparian/spring exclosures, fuels reductions, dispersed recreation, and mesquite treatment with herbicides would have less short-term impacts to PNVTs because of their smaller areas of impact across the project area.
There are no identified important bird areas (IBA) within the project area; however, the Aqua Fria National Monument, an identified IBA, is adjacent to the south and west boundary. The proposed
35 Agua Fria Grasslands Improvement Project activities would not affect this IBA. There are no identified over-wintering areas near the project area.
Overall, the project may have unintentional take of species associated with the PNVTs being treated, but the level of take would not have a measurable negative effect on migratory bird populations in the project area.
Cumulative Effects
This analysis takes into account past, present, and reasonably foreseeable actions. The cumulative effects area is the 6th code sub-watersheds located within and adjacent to the project area. There would be no effects to any analyzed species within the Bishop Creek 5th code watershed because of the small area affected, distance to species and their habitats, and the implementation of best management practices in the project area. The cumulative effects include the following actions that have had an effect on species or habitats within the project area.
The Cave Creek Fire Complex burned 10,500 acres within the Sycamore Creek and Indian Creek sub- watersheds. There were some moderate to high burn severities associated with the Piñon- Juniper Evergreen Shrub and Interior Chaparral PNVTS in both watersheds. The fire occurred on steep slopes adjacent to Gila chub habitat and also partially in riparian zones within species occupied habitat. The sediment and ash transport during monsoon events decreased pool size and depths. The aquatic habitat within these sub-watersheds is still impacted by in-stream sediment loading from this fire.
The Butte Fire burned about 8,000 acres within the Little Ash Creek sub-watershed. The majority of the fire occurred in the Semi-Desert Grassland PNVT and had low burn severity. This resulted in positive effects to the vegetation.
The on-going Pronghorn Corridor Habitat Improvement Project spans 5,750 acres of Semi-Desert Grassland and Juniper Grassland PNVTs within the Sycamore and Indian Creek sub-watersheds. It includes hand thinning of juniper, followed by pile burning the slash. The indirect effects to aquatic species and habitat have been mitigated by 300-foot SMZs with fire restrictions along Indian Creek and 50-foot SMZs on smaller drainages.
In the early 1990s, a 30 acre personal use fuelwood sale was used to thin juniper in the Cienega Creek sub-watershed. Around the same time, a 100 acre small sale also occurred on Tule Mesa in the Sycamore Creek sub-watershed. The purpose of this sale was to remove even-aged juniper trees and recreate historic spatial and structural diversity in the vicinity of Tule Tank. Both of these treatments resulted in reduced tree canopy cover and increases in shrub and grass cover.
Livestock grazing occurs throughout the project area. Occupied habitats in Little Sycamore and Indian Creeks have exclosures in place to restrict livestock access, and portions of Sycamore Creek are canyon-bound, which limits accessibility for livestock. Livestock grazing has short- term effects to both riparian vegetation (herbaceous and woody plant species), and to water quality from waste deposits in or near habitat. The impacts to aquatic habitat and riparian areas from project activities would be minimized through the application of BMPs and adherence to
36 Verde Ranger District, Prescott National Forest applicable standards and guidelines described in the Forest Plan and specified in Allotment Management Plans, and therefore would not add notably to other impacts.
Roads and trails that cross species suitable or occupied habitat on Little Sycamore and Sycamore Creek have localized impacts to streambanks and water quality. Current road maintenance on roads within the project area is not adequate to reduce runoff and sediments to drainages downstream to species habitat.
The effects from either the proposed action or the mesquite treatment alternative, if added to the listed cumulative effects considerations, would not change existing populations, habitat conditions, or primary constituent elements of critical habitat for the analyzed species within the project area.
Soils and Watershed
This section summarizes the potential impacts of the proposed action and the mesquite treatment alternative on soils and watershed conditions within the Agua Fria Grasslands analysis area. The full analysis can be found in the Agua Fria Grasslands Improvement Project Soils and Watershed Specialist Report (Forest Service, 2014d) and the Agua Fria Grasslands Improvement Project Herbicide Application Analysis (Forest Service, 2014j)..
Background
Soil condition is an evaluation of soil quality or the capacity of the soil to function within ecosystem boundaries to sustain biologic productivity, maintain environmental quality, and promote plant and animal health. It is important for watershed health because of the ecological services which the soil provides. To determine soil condition, a qualitative rating system was developed within the Forest Service Southwest Region to evaluate soil quality based on an interpretation of several factors that affect soil function. The primary soil functions evaluated are: the ability to resist erosion, the ability to infiltrate water, and ability to recycle nutrients. These are evaluated using indicators including rill and gully erosion, pedestalling, erosion pavement, soil deposition, surface (“A”) horizon, and vegetative community composition. Soil condition classes are defined as:
Satisfactory - Indicators signify that soil function is being sustained and soil is functioning properly and normally. The ability of soil to maintain resource values and sustain outputs is high.
Impaired - Indicators signify a reduction of soil function. The ability of soil to function properly has been reduced and/or there exists an increased vulnerability to degradation. An impaired category should signal land managers that there is a need to further investigate the ecosystem to determine causes and degrees of decline in soil functions. Changes in management practices or other preventative actions may be appropriate.
Unsatisfactory - Indicators signify that loss of soil function has occurred. Degradation of vital soil functions result in the inability of soil to maintain resource values, sustain
37 Agua Fria Grasslands Improvement Project
outputs, and recover from impacts. Soils rated in the unsatisfactory category are candidates for improved management practices or restoration designed to recover soil functions.
The US Forest Service Manual (FSM), chapter 2520 defines watershed condition as “The state of a watershed based upon physical and biological characteristics and processes affecting hydrologic and soil functions.” Watershed condition, or watershed health, on the Prescott NF varies depending on the amount of disturbance that has occurred within each watershed and the effect of the disturbance on the natural integrity of the sub-watershed (6th code) as a whole.
The USDA Strategic Plan for FY 2010-2015 (Forest Service, 2010) targets the restoration of watershed and forest health as a core management objective of the National Forests and Grasslands. A National Watershed Condition Team was formed to develop a nationally consistent, science-based approach to classify the condition of all National Forest System watersheds and to develop outcome-based performance measures for watershed restoration. The result was the six- step Watershed Condition Framework. The Watershed Condition Classification (WCC) system (Forest Service, 2011) is the first step in this process.
Human caused disturbances that can adversely affect a watershed's condition include the location of National Forest System and non-system roads, mining, recreation, livestock grazing, and timber harvest. The severity of effects is influenced in part by the local terrain, fire regime, precipitation, and potential geological hazards. Changes in watershed condition are reflective of changes in the long-term reliability of a watershed to provide the expected water quality and quantity. Most conditions leading to poor ratings are associated with high road densities, livestock grazing, and mining within the national forest. Watershed conditions are described in the Forest Service Manual (FSM 2521.1) using three classes:
Class 1 watersheds exhibit high geomorphic, hydrologic, and biotic integrity relative to their natural potential condition (Functioning or Good).
Class 2 watersheds exhibit moderate geomorphic, hydrologic, and biotic integrity relative to their natural potential condition (At Risk or Fair).
Class 3 watersheds exhibit low geomorphic, hydrologic, and biotic integrity relative to their natural potential condition (Impaired or Poor).
These assessments are general in scale and do not consider site specific analyses required for proposed project specific activities.
Affected Environment
Soil Conditions
The TEUI map units used in this analysis represent similarity at a fine scale based on soils, landform, topography, slope, geology, climate, and vegetation. The soil condition classes defined above are used to describe soil conditions within each TEUI, and can vary across TEUIs
38 Verde Ranger District, Prescott National Forest associated with the same PNVT. Below is a description of soil conditions by TEUI as grouped according to PNVT.
Piñon-Juniper Evergreen Shrub
TEUI 430, 432, 446, 461, 462, 464, 466, 479, 485, 491
Within the Piñon-Juniper Evergreen Shrub PNVT, the soils in TEUI 430, 446, 466, and 479 have been rated in satisfactory condition. These soils are generally stable, with functional hydrologic processes and nutrient cycling. There is high variability in vegetation structure and composition, due primarily to landscape form and position. Pockets of dense woody cover may have limited litter and organic matter production, reducing the capability of the soil to promote proper hydrologic function, stability, and nutrient cycling.
Soils associated with TEUI 432, 461, 462, 464, 485, and 491 within the PNVT were determined to be in impaired condition. In TEUI 432, 461, 462, and 464, the herbaceous cover is variable but generally below TEUI potential. This results in large areas with low basal cover (i.e. 462 and 464) and limited areas with low surface litter (i.e. 432 and 461). In some areas of TEUI 432 and 461, there is evidence of compaction. Compaction, when combined with reduced herbaceous cover, has resulted in soil instability due to a decrease of water infiltration and an increase in runoff. Woody cover is generally similar to TEUI potential, however, there is some variability. Areas with dense woody cover can experience a loss of herbaceous ground cover, which could contribute to diminished soil conditions. TEUI 485 and 491 are productive due to deep soils and the ability to hold high levels of water within the soil profile. Subsequently, these map units are able to support a high level of vegetation structural diversity. However, within the project area there are large areas exhibiting high levels of woody cover with minimal graminoid cover and low vegetative ground cover.
Semi-Desert Grassland
TEUI 370, 371, 372, 373
The soils associated with TEUI 371 in the Semi-Desert Grassland PNVT were rated in satisfactory condition. The basal cover is above potential for the TEUI and litter levels are generally below potential. Localized areas of soil instability have been noted and can be attributed to the low litter levels.
The remainder of the soils associated with TEUIs in this PNVT are in impaired condition. Vegetative ground cover levels are low, which can result in a reduced nutrient cycling capability, increased runoff, and increased soil loss. Some areas are experiencing soil compaction, resulting in decreased water infiltration and increased runoff.
Juniper Grassland
TEUI 427, 428, 431, 463, 490
39 Agua Fria Grasslands Improvement Project
In the project area, TEUI 431 in the Juniper Grassland PNVT has a soil condition rating of Satisfactory and vegetative ground cover levels similar to potential. These soils are stable and functional.
In TEUI 427 and 428, the soils are in impaired condition. Both map units have vegetative ground cover levels below potential resulting in a reduction in nutrient cycling. In addition, TEUI 427 has experienced soil instability and there are some areas where the woody cover is above potential. This high woody cover has had a negative impact on the establishment of herbaceous cover and has resulted in accelerated soil loss in the form of sheet erosion.
TEUI 463 and 490 are in unsatisfactory soil condition. Historical soil loss and potential disturbance to the soil surface has resulted in the loss or partial loss of the A-horizon. This has resulted in the loss and lack of internal soil and surface organic matter and exposing subsurface soils with high clay levels. This has negatively impacted soil structure, soil aeration, infiltration, and nutrient cycling. Run-off has increased but armoring from rock cover has minimized soil loss. Herbaceous cover establishment and subsequent recruitment of surface and soil organic matter has been limited due to the high levels of juniper canopy cover.
Interior Chaparral
TEUI 425, 436, 448, 457, 475, 476, 551
The majority of the map units in the Interior Chaparral PNVT are in satisfactory condition. Normally, the dense shrub cover provides a high level of litter that is well distributed across the landscape. This high litter level provides organic matter that enhances the hydrologic, stability, and nutrient cycling soil function.
The soil associated with TEUI 425 is in impaired condition due to a lack of vegetative ground cover within the shrub interspaces. Low ground cover makes the soils vulnerable to increased run off and soil loss which decreases its ability to retain moisture and nutrients for plant productivity. The shrub cover on this TES map unit is above potential and the herbaceous cover is lower than potential.
The soil associated with TEUI 457 is also in impaired condition. A high level of shrub cover in isolated areas has resulted in minimal vegetative ground cover in the interspaces. This has led to an accelerated rate of erosion in these areas. However, the litter production of the shrub species has generally resulted in stable soils with minimal soil loss.
Watershed Conditions
The analysis area is located in portions of two 5th code watersheds: Ash Creek / Sycamore Creek and Bishop Creek, and these watersheds are further divided into nine sub-watersheds. The hierarchical relationship of these hydrologic units is displayed below in tables 5 and 6, which show the acres of each watershed and sub-watershed located within the project area.
40 Verde Ranger District, Prescott National Forest
Table 5. Ash Creek / Sycamore Creek 5th and 6th Code Watershed Acres
HUC HUC Name Acres HUC 5 Acres HUC 6
1507010201 Ash Creek / Sycamore Creek 166,753
150701020101 Cienega Creek 12,905
150701020104 Dry Creek 8,774
150701020105 Little Ash Creek 28,652
150701020106 Lower Ash Creek 3,594
150701020401 Little Sycamore Creek 10,378
150701020402 Sycamore Creek 21,038
Total 85,341
Table 6. Bishop Creek 5th and 6th Code Watershed Acres
HUC HUC Name Acres HUC 5 Acres HUC 6
1507010204 Bishop Creek 151,326
150701020404 Indian Creek 9,547
150701020405 Silver Creek 2,754
150701020406 Bishop Creek 99
Total 12,400
All of the sub-watersheds in the project area were assigned a watershed condition rating (table 7) based on the twelve key indicators identified in the WCC. Six of the sub-watersheds in the project area were rated as “At Risk” condition, two were rated as “Functioning Properly”, and one was rated “Impaired Function”.
The majority of the Silver Creek and Bishop Creek sub-watersheds are located on the Tonto NF and their watershed conditions were assessed as part of the WCC scoring process on that forest. Watershed condition ratings were assessed for these sub-watersheds as a whole and may not reflect conditions in the sub-parts located within the project area.
41 Agua Fria Grasslands Improvement Project
Table 7. Agua Fria Overall Watershed Condition Assessment
Condition Class Sub-watersheds
Little Ash Creek 1 - Functioning Indian Creek
Cienega Creek
Dry Creek
Lower Ash Creek 2 - At Risk Little Sycamore Creek
Sycamore Creek
Silver Creek
3 - Impaired Bishop Creek
The twelve indicators are grouped into four watershed process categories: Aquatic Physical, Aquatic Biological, Terrestrial Physical, and Terrestrial Biological. The Aquatic Physical category contains three indicators; Water Quality, Water Quantity, and Aquatic Habitat. The parameter of water quality is composed of two attributes; Listed by the State or US EPA as an impaired water, and other water quality problems The Aquatic Biological and Terrestrial Physical categories each have two indicators; Aquatic Biota and Riparian/Wetland Vegetation for the Aquatic Biological category, Roads & Trails and Soils for Terrestrial Physical. The remaining five indicators are in the Terrestrial Biological category; Fire Regime or Wildfire, Forest Cover, Rangeland Vegetation, Terrestrial Invasive Species, and Forest Health. Each of the indicators are assessed and combined to produce a watershed score which falls into one of three classes. The sub-watersheds’ conditions, by condition class indicator, is shown below in table 8. Definitions for the condition class indicator ratings can be found in the Watershed Condition Classification Technical Guide (Forest Service, 2011) and additional discussion of the condition indicators can be found in Agua Fria Grasslands Improvement Project Soils and Watershed Specialist Report (Forest Service, 2014d).
Table 8. Sub-watershed conditions, by indicator
Condition
1. Water Quality 2. Water Quantity 3. Aquatic Habitat 4. Aquatic Biota 5. Riparian Veg. 6. Roads & Trails 7. Soils 8. Fire Regime 9. Forest Cover 10. Rangeland Veg. 11. Invasive Species 12. Forest Health
Cienega Good Fair Good Fair Good Poor Fair Fair ---- Poor Good Good Creek Dry Creek Good Good Fair Fair Fair Poor Poor Fair ---- Poor Good Good Little Ash Good Good Good Fair Good Poor Poor Fair ---- Fair Good Good Creek
42
Verde Ranger District, Prescott National Forest
Condition
1. Water Quality 2. Water Quantity 3. Aquatic Habitat 4. Aquatic Biota 5. Riparian Veg. 6. Roads & Trails 7. Soils 8. Fire Regime 9. Forest Cover 10. Rangeland Veg. 11. Invasive Species 12. Forest Health
Lower Ash Good Fair Good Good Fair Poor Poor Fair ---- Poor Good Good Creek Little Sycamore Good Good Good Fair Good Poor Poor Fair ---- Fair Good Good Creek Sycamore Good Good Good Fair Fair Poor Fair Fair Good Fair Good Good Creek Indian Good Fair Good Good Good Poor Poor Fair ---- Fair Good Good Creek Silver Poor Fair Poor Good Poor Fair Poor Fair ---- Good Good Good Creek Bishop Poor Fair Poor Fair Poor Poor Poor Fair ---- Good Good Good Creek Indicators associated with Aquatic Habitat, Aquatic Biota, Fire Regime, Forest Cover, Rangeland Vegetation, Terrestrial Invasive Species, and Forest Health were not part of the analysis for this project. The scores for these indicators were developed by specialists in the respective resource areas from a forest level analysis, rather than at the project level. Project level elements applicable to the proposed action are assessed according to resource within this Environmental Analysis.
Cienega Creek
Table 9. Cienega Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
Piñon-Juniper 430, 432, 461, 1,463 acres 7,818 acres - Evergreen Shrub 462, 464, 485
Semi-Desert Grassland 372, 373 - 76 acres -
427, 428, 431, Juniper Grassland 759 acres 1,356 acres - 463
Interior Chaparral 436, 448, 551 897 acres - -
Total 3,119 acres 9,250 acres -
Cienega Creek sub-watershed has about 12,900 acres within the project area and its overall watershed condition has been classified as “At Risk”. It was assessed as ”Good” or “Fair” for most categories, with the exception of “Road and Trails” and “Rangeland Vegetation” which were rated “Poor”. The “Soils” category was rated “Fair” for this sub-watershed. Based on the TEUIs, about three-quarters (9,399 acres) of the project acreage within the sub-watershed was rated “Impaired” for soil condition, and about 25 percent (3,119 acres) was rated “Satisfactory”. No TEUIs were rated “Unsatisfactory”.
43 Agua Fria Grasslands Improvement Project
Within the project area, the sub-watershed contains 93 acres of riparian in TEUI 41. This Map Unit is part of the Mixed Broadleaf Deciduous Riparian Forest PNVT and soil conditions are impaired. Cienega Creek does not have surface water in most of the project area except for two springs and surface flow a short distance before it enters Ash Creek. The majority of Cienega Creek itself is intermittent flows, with some perennial water near and on the private land east of Interstate 17 and also for a short segment just west of the interstate.
Water quality for Cienega Creek was rated “Good” based on no impaired listing status, low levels of mining activity, and no other known water quality problems. Water quantity was rated “Fair” based on the number and location of wells registered with the Arizona Department of Water Resources
Originally, FR732 was in the floodplain of Cienega Creek and high flows often ran down the road. In 1993 the road was moved onto the slopes above the floodplain and the crossings were stabilized with jersey barriers. The jersey barriers are stabilized by rock and sediment has collected in the rock on the road side of the structures. This sediment collects water and cottonwood and ash initiate growth in the channel both above and below some of the crossings. Whether the water storage of the sediment is adequate to sustain the trees in dry years and if there is sufficient root anchorage to sustain the trees is questionable as neither species has much drought tolerance or flood resistance.
Dry Creek
Table 10. Dry Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
Piñon-Juniper 432 - 558 acres - Evergreen Shrub
Semi-Desert Grassland 370, 372, 373 - 8,181 acres -
Juniper Grassland 427 - 5 acres -
Interior Chaparral 436, 448, 551 - - -
Total - 8,744 acres -
Dry Creek sub-watershed has about 8,800 acres within the project area and its overall watershed condition has been classified as “At Risk”. It was assessed as ”Good” or “Fair” for most categories, with the exception of “Road and Trails”, “Soils”, and “Rangeland Vegetation” which were rated “Poor”. All of the TEUIs within the sub-watershed project area (8,776 acres) were rated “Impaired” for soil condition; none were rated “Satisfactory” or “Unsatisfactory”.
Within the project area, the sub-watershed contains 32 acres of riparian in TEUI 41. This Map Unit is part of the Mixed Broadleaf Deciduous Riparian Forest PNVT and soil conditions are impaired. The majority of Dry Creek itself is intermittent with about a quarter-mile reach of perennial water in the project area below the Dugas Road and also near the confluence with Little Ash Creek on BLM land. Ash Spring is a small spring site within the Dry Creek drainage. The
44 Verde Ranger District, Prescott National Forest extent of surface water is less than 100 feet. The site is open to livestock grazing use and has noticeable impacts from this use.
Two pastures on the V-Bar allotment east of I-17 were grazed every summer prior to 1983, causing the channel of Dry Creek to become downcut and compacted with limited vegetation and a narrow flow of water downstream of the Dugas Road bridge. At the time, no perennial water was found upstream of the bridge; however, cottonwoods and some willow grew above the channel but regeneration was usually grazed before it could grow above the reach of cattle. In 1984, a Time Control grazing system was implemented, leading to increased surface flows, the development of a sedge community, and the establishment of cottonwood and ash saplings within the riparian area.
A riparian site inspection of Dry Creek on the Todd allotment was done in 2006 and found the creek impaired with the trend not apparent. There was no diverse age class distribution for recruitment and recovery, however there was diverse composition. The creek was not vertically stable. Dry Creek in much of this section is shallow to bedrock and has intermittent surface water and sub-surface flow. Ash and cottonwood saplings will initiate growth but because of the shallow soil they cannot establish a root system capable of withstanding even moderate flooding. Perennial grass cover is high and provides bank protection.
Water quality for Dry Creek was rated “Good” based on no impaired listing status, low levels of mining activity, and no other known water quality problems. Water quantity was rated “Good” based on the number and location of wells registered with the Arizona Department of Water Resources
Little Ash Creek
Table 11. Little Ash Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
430, 432, 461, Piñon-Juniper 462, 464, 466, 2,002 acres 8,121 acres 131 acres Evergreen Shrub 479, 485, 491
Semi-Desert Grassland 372, 373 - 11,086 acres -
427, 428, 431, Juniper Grassland 728 acres 1,828 acres 655 acres 463, 490
425, 436, 457, Interior Chaparral 1,599 acres 226 acres - 475, 551
Total 4,329 acres 21,261 acres 786 acres
Little Ash Creek sub-watershed has about 28,600 acres within the project area and its overall watershed condition has been classified as “Functioning”, the best of the three condition classes and only one of two sub-watersheds in the project area to be classified as such. It was assessed as ”Good” or “Fair” for most categories, with the exception of “Road and Trails” and “Soils”, which were rated “Poor”. Based on the TEUIs, about 80 percent (23,141 acres) of the project acreage
45 Agua Fria Grasslands Improvement Project within the sub-watershed was rated “Impaired” for soil condition, and about 15 percent (4,329 acres) was rated “Satisfactory”. Approximately four percent of the acreage (1,019 acres) was rated “Unsatisfactory”.
Within the project area, the sub-watershed contains 621 acres of riparian in TEUI 34 (87 acres), and TEUI 41 (196 acres). TEUI 34 is part of the Cottonwood, Willow Riparian Forest PNVT and has an impaired soil condition rating. TEUI 41 is part of the Mixed Broadleaf Deciduous Riparian Forest PNVT and soil conditions are impaired. A riparian inspection was conducted in 2006 and Little Ash Creek was determined to be functioning properly with upward trend. It is perennial throughout its length, and the first three miles of stream are entirely on the Prescott NF. The vegetation age-class diversity and distribution was high and overstory trees are present; however, the herbaceous ground cover of sedges and rushes is lacking near the Yellowjacket bridge due to heavy recreational use. Past management actions have taken place to control human use in the dispersed recreation sites including road closures, vehicle barriers, and signing. These activities have stabilized the recreation impacts. Similar inspections were done in 1998 and 1999 with similar findings excepting that recreational impacts were greater.
Cattle on the Dugas, Todd and V Bar allotments obtain water in Little Ash Creek. Riparian site inspections on all three allotments document some impacts to the riparian area, but not enough to affect stream function or vegetation.
Water quality for Little Ash Creek was rated “Good” based on no impaired listing status, low levels of mining activity, and no other known water quality problems. Water quantity was also rated “Good” based on the number and location of wells registered with the Arizona Department of Water Resources.
Lower Ash Creek
Table 12. Lower Ash Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
Piñon-Juniper 432 - 63 acres - Evergreen Shrub
370, 371, 372, Semi-Desert Grassland 67 acres 3,277 acres - 373
Juniper Grassland 427 - 41 acres -
Interior Chaparral - - - -
Total 151 acres 3,434 acres -
Lower Ash Creek sub-watershed has about 3,600 acres within the project area and its overall watershed condition has been classified as “At Risk”. It was assessed as ”Good” or “Fair” for most categories, with the exception of “Road and Trails”, “Soils”, and “Rangeland Vegetation” which were rated “Poor”. Most of the TEUIs within the sub-watershed project area (3,434 acres)
46 Verde Ranger District, Prescott National Forest were rated “Impaired” for soil condition; only about four percent of the acreage (151 acres) was rated “Satisfactory”. No TEUIs were rated “Unsatisfactory”.
Within the project area, the sub-watershed contains 137 acres of riparian in TEUI 30 (84 acres) and TEUI 34 (53 acres). Both of these map units are within the Cottonwood, Willow Riparian Forest PNVT. TEUI 30 has satisfactory soil conditions and TEUI 34 is in impaired condition.
Water quality for Lower Ash Creek was rated “Good” based on no impaired listing status, low levels of mining activity, and no other known water quality problems. Water quantity was rated “Fair” based on the number and location of wells registered with the Arizona Department of Water Resources.
Little Sycamore Creek
Table 13. Little Sycamore Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
Piñon-Juniper 430, 432, 462, 733 acres 2,630 acres - Evergreen Shrub 464, 485
Semi-Desert Grassland 372, 373 - 2,804 acres -
427, 428, 431, Juniper Grassland 466 acres 519 acres 183 acres 490
Interior Chaparral 436 522 acres - -
Total 1,721 acres 5,953 acres 183 acres
Little Sycamore Creek sub-watershed has about 10,400 acres within the project area and its overall watershed condition has been classified as “At Risk”. It was assessed as ”Good” or “Fair” for most categories, with the exception of “Road and Trails” and “Soils” which were rated “Poor”. About 80 percent (8,322 acres) of the TEUI project acreage within the sub-watershed was rated “Impaired” for soil condition; about 17 percent (1,721 acres) was rated “Satisfactory”, and about two percent (183 acres) “Unsatisfactory”.
Within the project area, the sub-watershed contains 260 acres of riparian in TEUI 41 (106 acres). This Map Unit is part of the Mixed Broadleaf Deciduous Riparian Forest PNVT and soil conditions are impaired. Little Sycamore Creek is perennial interrupted with a couple of dry reaches along its length.
Water quality for Little Sycamore Creek was rated “Good” based on no impaired listing status, low levels of mining activity, and no other known water quality problems. Water quantity was also rated “Good” based on the number and location of wells registered with the Arizona Department of Water Resources.
47 Agua Fria Grasslands Improvement Project
Sycamore Creek
Table 14. Sycamore Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
430, 432, 446, Piñon-Juniper 461, 462, 464, 5,602 acres 4,387 acres 146 acres Evergreen Shrub 466, 479, 485, 491
Semi-Desert Grassland 372, 373 - 572 acres -
427, 428, 431, Juniper Grassland 1,138 acres 325 acres 2,402 acres 490
425, 436, 448, Interior Chaparral 2,291 acres 643 acres - 457, 475, 551
Total 9,031 acres 5,927 acres 2,548 acres
Sycamore Creek sub-watershed has about 21,000 acres within the project area and its overall watershed condition has been classified as “At Risk”. It was assessed as “Good” or “Fair” for all categories, with the exception of “Road and Trails” which was rated “Poor”. About 45 percent (9,578 acres) of the TEUI project acreage within the sub-watershed was rated “Satisfactory” for soil condition; about 40 percent (8,816 acres) was rated “Impaired”, and about twelve percent (2,548 acres) “Unsatisfactory”.
Sycamore Creek flows approximately 23 miles before leaving the Prescott NF; approximately one mile of this distance on is private land. The majority of the stream is perennial interrupted flows with long dry stretches near Dry Creek and the last two miles. Nelson Place Spring, on private land, is the source of the flow in the upper creek, and the South Prong of Sycamore Creek joins the mainstem about four miles down from Nelson Place. A short distance below the confluence the water flow becomes sub-surface and riparian vegetation is patchy. Surface flow resumes about one mile upstream of the FR677 crossing and is continuous until leaving the forest on private land in Dugas.
Within the project area, the sub-watershed contains 710 acres of riparian in TEUI 41 (462 acres), and TEUI 50 (64 acres). Both of these map units are within the Mixed Broadleaf Deciduous Riparian Forest PNVT. TEUI 50 has satisfactory soil conditions and TEUI 41 is in impaired condition.
Riparian site inspections in 2008 on the upper section of Sycamore Creek report conditions as good for channel stability and for riparian vegetative diversity and community structure. Sediment from the Cave Creek Fire was deposited in pools below the confluence with South Prong reducing the pools’ capacity.
Although the watershed condition indicator for Water Quality was rated “Good” for this sub- watershed, water quality testing in Sycamore Creek by the Arizona Department of Environmental Quality within the last three years has shown two occurrences of e. coli levels above state
48 Verde Ranger District, Prescott National Forest standards for partial body contact. These exceedances occurred in samples collected in September of 2011, and June of 2012, and were not noted to be associated with stormflow events. It is expected that this could lead to an impaired listing for Sycamore Creek under section 303(d) of the Clean Water Act. Water quantity was rated “Good” based on the number and location of wells registered with the Arizona Department of Water Resources.
Indian Creek
Table 15. Indian Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
Piñon-Juniper 430, 432, 464, 1,485 acres 4,778 acres - Evergreen Shrub 479
Semi-Desert Grassland 372, 373 - 1,393 acres -
Juniper Grassland 427, 428, 431 1,072 acres 571 acres -
Interior Chaparral - - - -
Total 2,557 acres 6,742 acres -
Indian Creek sub-watershed has about 9,500 acres within the project area and its overall watershed condition has been classified as “Functioning”, the best of the three condition classes and only one of two sub-watersheds in the project area to be classified as such. It was assessed as ”Good” or “Fair” for most categories, with the exception of “Road and Trails” and “Soils”, which were rated “Poor”. About 25 percent (2,557 acres) of the TEUI project acreage within the sub- watershed was rated “Satisfactory” for soil condition; about 70 percent (6,776 acres) was rated “Impaired”, and the balance (222 acres) was not rated for soil condition. No TEUIs were rated “Unsatisfactory”.
Within the project area, the sub-watershed contains 256 acres of riparian in TEUI 41 (34 acres). This Map Unit is part of the Mixed Broadleaf Deciduous Riparian Forest PNVT and soil conditions are impaired. Indian Creek has two reaches with perennial water on the forest, but there is limited water within the project area as it is mainly ephemeral from the headwaters downstream to the Prescott NF boundary. One perennial reach is on the east side of FR677, and the other is upstream of private land near the west forest boundary north of FR9601D. The water at both sites is fenced and water is piped to troughs outside the exclosures.
Water quality for Indian Creek was rated “Good” based on no impaired listing status, low levels of mining activity, and no other known water quality problems. Water quantity was rated “Fair” based on the number and location of wells registered with the Arizona Department of Water Resources.
49 Agua Fria Grasslands Improvement Project
Silver Creek
Table 16. Silver Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
Piñon-Juniper 430, 432, 479, 693 acres 73 acres - Evergreen Shrub 485, 491
Semi-Desert Grassland - - - -
Juniper Grassland 431 13 acres - -
425, 436, 448, Interior Chaparral 1,457 acres 194 acres - 475, 476
Total 2,163 acres 267 acres -
Silver Creek sub-watershed has about 2,570 acres within the project area and its overall watershed condition has been classified as “At Risk”, however, the condition indicators were not assessed on the Prescott NF due to limited extent on the forest; the ratings reflect conditions on the portion of the sub-watershed on the adjacent Tonto NF. About 80 percent (2,163 acres) of the TEUI project acreage within the sub-watershed was rated “Satisfactory” for soil condition; about 20 percent (592 acres) was rated “Impaired”, and no TEUIs were rated “Unsatisfactory”.
Within the project area, the sub-watershed contains 44 acres of riparian in TEUI 41. This Map Unit is part of the Mixed Broadleaf Deciduous Riparian Forest PNVT and soil conditions are impaired.
Water quality for Silver Creek was rated “Poor”, and water quantity was rated “Fair” based on ratings prepared by the Tonto NF.
Bishop Creek
Table 17. Bishop Creek soil condition ratings
Soil Condition PNVT TEUI Satisfactory Impaired Unsatisfactory
Piñon-Juniper 485, 491 - 5 acres - Evergreen Shrub
Semi-Desert Grassland - - - -
Juniper Grassland - - - -
Interior Chaparral 436 83 acres - -
Total 83 acres 5 acres -
Bishop Creek sub-watershed has only 99 acres within the project area, and its overall watershed condition has been classified as “Impaired” based on the assessment performed by the Tonto NF. There are only three TEUI map unit types within the project area, 436, 485, and 491. TEUI 436 covers about 85 percent (83 acres) of the project acreage within the sub-watershed and was rated
50 Verde Ranger District, Prescott National Forest
“Satisfactory” for soil condition; TUEI 485 and 491 combined cover the remaining 16 acres and were rated “Impaired”.
The sub-watershed does not contain any riparian acreage within the project area.
Water quality for Bishop Creek was rated “Poor”, and water quantity was rated “Fair” based on ratings prepared by the Tonto NF.
Environmental Consequences
No Action
No action would mean that the existing soil and watershed conditions and trends would remain largely unchanged into the foreseeable future. TEUIs with Impaired or Unsatisfactory soils would be unlikely to improve without management actions such as vegetation treatments or road closures. The lack of project level mitigations would increase the chance of watershed degradation due to the concentration of impacts from moderate to high soil burn severity events.
The e. coli water quality exceedances are largely thought to be a non-point source issue. As such, the no action alternative would likely maintain or potentially further degrade water quality for e. coli, due to current soil and grass vegetation conditions.
Proposed Action
During implementation it will be important to follow the project mitigations regarding the extent and timing of wildland fire treatments to protect the structure, function, and productivity of soils within the project area. The watershed specialists associated with developing this proposed action have advised that not all ecosystems are capable of supporting burn intensities high enough to produce adverse soil burn severity effects. The Grassland PNVTs (Semi-Desert Grassland and Juniper Grassland) typically do not have the fuel loading to support heat residence times and intensities to significantly alter soil properties. The Piñon-Juniper Evergreen Shrub PNVT does have adequate fuel loading and arrangement to support heat residence times and intensities to significantly alter soil properties. If the burn intensities are high enough, they could produce adverse soil burn severity effects, as defined in appendix A.
Soil burn severity identifies how much the soil surface has changed due to fire; in essence, how much fire has influenced the soils ability to provide stability, infiltrate and store water, and allow nutrient cycling and vegetation growth. The low end of this scale has minimal impact to these services but will still influence them because the mere definition of “low” soil burn severity suggests the fire has altered the soil in some fashion. With a high soil burn severity, the alteration to the soils ability to provide stability, infiltration, and allow nutrient cycling and plant production can be significantly altered. Analysis and prior fire history have shown that the cumulative impact of moderate to high soil burn severity fires within the same sub-watershed would be counter- productive to the intended benefits of the proposed treatments.
To mitigate potential negative soil and watershed impacts, the Prescott NF’s Soil Scientist, Hydrologist, and Ecologist have recommended a maximum of 20 percent of any watershed be
51 Agua Fria Grasslands Improvement Project intentionally subjected to moderate to high soil burn severity during a given year, and no more than 40 percent within five years. Twenty percent is recommended rather than 15 percent because other prescription elements are integrated, such as the establishment of SMZs, fire avoidance on very steep slopes, and the general mosaic nature associated with prescribed fires. Allowing moderate to high soil burn severity on up to 40 percent of the sub-watershed in five years is intended to allow some recovery period. If the 40 percent threshold is exceeded, there can be an observed and undesirable response to sedimentation and peak flow.
Across all of the sub-watersheds, the soil units subjected to prescribe fire would show a short- term increase in soil loss due to the loss of ground cover. The exposure to the heat of the burn may also influence soil structure and soil hydrologic dynamics. However, prescribe burns can also result in a longer-term positive response by improving soil fertility through expedited nutrient cycling, promoting vegetation vigor, improving herbaceous response, and improving soil stability due to increased ground cover. Soil resources would also benefit from altering the vegetative successional structure to provide more opportunity for early-stage vegetation.
A combination of hand thinning and mechanical treatment of juniper species in the Juniper Grassland PNVT may occur. The mechanical treatments would benefit soil and watershed resources by thinning dense woody cover and providing additional vegetative ground cover for the soil resources. Retention of slash would protect the soil surface and promote favorable graminoid response by protecting the soil surface from rain impact, regulating soil temperatures, and retaining soil moisture levels.
Mechanical thinning could result in soil compaction and displacement, however, this would be mitigated through timing restrictions to limit activity to periods when soils are dry and not susceptible to load bearing stresses. Slash scattered on site would provide immediate cover from rain splash erosion, attenuate soil temperatures, assist in retaining soil moisture, and provide organic nutrients favorable for herbaceous establishment and soil function.
Prescribed burning would be expected to maintain conditions for soils rated as “Satisfactory” and to improve functional resiliency for all soil condition classes. It would also help control woody species, allowing for increased graminoid species establishment and coverage. Vegetation vigor would be improved through the use of fire to remove decadent biomass, expediting nutrient cycling and increasing the nutrients available for plant uptake and germination. This is of particular importance where shrub species are the dominant species. Increased ground coverage and plant vigor are favorable to the development of soil structure, contributing to the soils ability to increase infiltration, decrease run-off, and stabilize the soil surface from overland flow and rain splash erosion. Soils in less than satisfactory condition are expected to benefit from these treatments, and some soil conditions may trend towards a satisfactory rating, depending of the specific map unit.
All of the Riparian TEUIs (30, 34, 41, 42, and 50) have been designated as fire avoidance areas and will not receive any direct treatment. It should be noted that fire may still move into these TEUIs from adjacent treatment areas, but the fire intensity and rate of spread, and thus the impacts, would be expected to be low. Indirect impacts due to potential higher flows and sediment from upland treatments would be minimized by limiting the amount of burning activity
52 Verde Ranger District, Prescott National Forest within each watershed and providing a “buffer/filter” strip of 150ft to 300ft along drainages. Potential higher flows and sediment yield would be short lived and eventually would improve as upland conditions improve over time as vegetation and soils recover. Prescribe fire would release nutrients that would be transported to riparian ecosystems that would promote riparian vegetation vigor and further recruitment of riparian vegetation that could improve its density.
Cienega Creek
It could be reasonably concluded that the proposed action would benefit the soil and watershed conditions in this “Functioning At Risk” sub-watershed.
The roughly 7,800 acres of proposed treatment in the Piñon-Juniper Evergreen Shrub PNVT would provide the most improvement to watershed conditions in the Cienega Creek sub- watershed of any single action. Fuel loading in this PNVT is highly variable, but the primary carrier is chaparral shrub species. These species are associated with high burn intensity fires, which will consume the chaparral canopy cover and lead to hydrophobic soil conditions. Negative impacts to the soil resources would be minimized with the implementation of project mitigation described in appendix A and consideration of the prescribed burn suitability criteria in appendix D. Performing prescribe burns during favorable burn periods with higher fuel moisture contents, lower wind speeds, higher humidity, and lower ambient temperatures, would create a mosaic burn pattern, leaving desired unburned patches of shrub canopy and litter.
The reduction in woody species cover within the Piñon-Juniper Evergreen Shrub PNVT would allow for increased recruitment and retention of herbaceous surface and sub-surface biomass. This would benefit soil structure and function by increasing available organic matter and providing stability. In areas where landscape position and soil properties are favorable, soil function would be improved through increased shrub species vigor leading to higher levels of litter. This would also improve soil condition by reducing erosion and gradually rebuilding the soil structure and the organic component of the A horizon.
These treatments would be expected to improve impaired soil conditions in TEUI 432, 461, 462, and 464 – about 26 percent of the total acres within Cienega Creek. However, it is unlikely that the soil condition rating would change to Satisfactory in these TEUIs due to pre-existing low herbaceous cover, vegetative ground cover, and compaction in areas. The Satisfactory soil condition rating for TEUI 430 would be retained because these units have been identified as “fire avoidance” areas due to their very steep slopes.
The seven percent of the sub-watershed treatment acres in the Interior Chaparral PNVT (TEUI 436, 448, and 551) would maintain a Satisfactory soil condition rating and would see an improvement in soil resiliency. Impacts would be similar to those described for the Piñon-Juniper Evergreen Shrub PNVT because the dominance of shrub species.
About 1,200 acres of treatment are proposed in TEUI 427 in the Juniper Grassland PNVT. This represents approximately 9 percent of the treatment acres within the sub-watershed. Mechanical treatments, hand thinning, and fire would be used to treat dense juniper stands and control woody species regeneration. Juniper thinning combined with wildfire treatments would decrease the high
53 Agua Fria Grasslands Improvement Project juniper cover levels and promote an increase in herbaceous cover. This would improve total vegetative ground cover levels, promote infiltration, and decrease the elevated soil loss rate. Mechanical thinning could result in soil compaction and displacement, however, this would be mitigated through timing restrictions to limit activity to periods when soils are dry and not susceptible to load bearing stresses.
The fire severity in the Semi-Desert Grassland (TEUI 372 and 373) and Juniper Grassland (TEUI 427) PNVTs from the planned prescribe burns is expected to be low due to light fuel loading. This would result in minimal soil heating with the occasional exception for pockets of heavy fuel associated with juniper and shrub species. This could lead to some hydrophobicity (water repellency) in these pockets. Long-term benefit could include improved nutrient cycling, vegetation vigor, and vegetative ground coverage. Vegetative ground cover and soil function improvements are expected to result in a change in the soil condition rating from Impaired to Satisfactory for this TEUI. In addition, impaired soil conditions in TEUI 372 and 373 are expected to improve, but not achieve a Satisfactory rating due to pre-existing low herbaceous cover, vegetative ground cover, compaction in areas, and historical accelerated overland flow.
Roads concentrate precipitation run-off and can be a major source of sediment, impacting watershed condition by impacting water quality and quantity. The Poor rating for the Roads and Trails watershed condition indicator (table 8), means that there is a higher probability that the hydrologic conditions have been substantially altered by the roads and trails. These hydrologic conditions include the stream channels and flows, sediment amounts, water quality, and riparian conditions. The proposed action would address this issue by decommissioning all or part of six roads within the sub-watershed – FR9602A, FR9602G, FR9602H, FR9602K, FR9712G, and FR9712H – totaling 5.75 miles. The decommissioning of one and a half miles of FR9602A is of particular note as it has been identified as crossing soils that have a high potential for erosion and compaction. The rest of FR9602A would be subject to seasonal travel restrictions to minimize use when the roadbed is wet and subject to compaction. The decommissioning and removal of these roads from the transportation system would help mitigate impacts on water quality and sediment loads within the sub-watershed.
Another six roads – FR505A, FR9602E, FR9602H, FR9606E, FR9606H, and FR9710G – totaling 14.55 miles within the sub-watershed would be closed to public use. These roads cannot be decommissioned as they are needed for administrative purposes – often to access stock tanks or other range improvements. However, limiting their use would help reduce run-off, erosion, and sedimentation from these roads, improving watershed conditions.
The watershed condition indicator for Rangeland Vegetation has been rated Poor for the Cienega Creek sub-watershed (table 8). In sub-watersheds that have been rated as “Poor”, the composition of the vegetation has been greatly reduced or unacceptably altered compared to the natural potential of the area. In the Juniper Grassland PNVT, tobosa grass is the most abundant forage for livestock. It is resistant to fire mortality and can sprout and regrow quickly after top-kill by fire and thus could respond well to the proposed wildland fire treatments. Given a sufficient recovery period, the Rangeland Vegetation condition indicator would be expected benefit from the
54 Verde Ranger District, Prescott National Forest vegetation treatments on 2,500 acres of this PNVT to reduce shrub and tree cover and allow for an increase in the herbaceous species and annual forb cover.
Dry Creek
It could be reasonably concluded that the proposed action would benefit the soil and watershed conditions in this “Functioning At Risk” sub-watershed.
Most of the Dry Creek sub-watershed (86 percent) is Semi-Desert Grassland PNVT in three TEUIs - 370, 372, and 373.). The Grassland PNVT fuel types are primarily fine herbaceous fuels that usually burn quickly and generally do not fully consume vegetative ground cover. The result is little heat flux to the soil, which seldom alters the soil surface. Because of this, little to no change in soil loss rates is expected from the fire treatments and they would result in a short term improvement to nutrient cycling, plant vigor, and vegetative ground cover. Impaired soil conditions would improve but not change condition class due to pre-existing low herbaceous cover, vegetative ground cover, compaction in areas, and historical accelerated overland flow.
In the Piñon-Juniper Evergreen Shrub TEUI 432, the soil condition would improve, but would be expected to remain in an impaired condition due to its compaction and pre-existing soil loss. Fuel loading in this PNVT is highly variable, but the primary carrier is chaparral shrub species. These species are associated with high burn intensity fires, which will consume the chaparral canopy cover and lead to hydrophobic soil conditions. Negative impacts to the soil resources would be minimized with the implementation of project mitigation described in appendix A and consideration of the prescribed burn suitability criteria in appendix D. Performing prescribe burns during favorable burn periods with higher fuel moisture contents, lower wind speeds, higher humidity, and lower ambient temperatures, would create a mosaic burn pattern, leaving desired unburned patches of shrub canopy and litter. The reduction in woody species cover, would allow for increased recruitment and retention of herbaceous surface and sub-surface biomass. This would benefit soil structure and function by increasing available organic matter and providing stability. In areas where landscape position and soil properties are favorable, soil function would be improved through increased shrub species vigor leading to higher levels of litter. This would also improve soil condition by reducing erosion and gradually rebuilding the soil structure and the organic component of the A horizon.
Roads concentrate precipitation run-off and can be a major source of sediment, impacting watershed condition by impacting water quality and quantity. The Poor rating for the Roads and Trails watershed condition indicator (table 8), means that there is a higher probability that the hydrologic conditions have been substantially altered by the roads and trails. These hydrologic conditions include the stream channels and flows, sediment amounts, water quality, and riparian conditions. The proposed action would decommission two roads within the sub-watershed, FR68C and FR9601Y. The decommissioning and removal of these roads from the transportation system would help mitigate impacts on water quality and sediment loads within the sub- watershed.
All or parts of three roads within the sub-watershed – FR9601X, FR9602S, and FR9625K, totaling about two miles – would be closed to public use. Access would be restricted for
55 Agua Fria Grasslands Improvement Project approximately one mile on FR9601X from April 1st to June 30th to protect pronghorn fawning habitat. The rest of FR9601X would be subject to seasonal travel restricts to minimize use when the roadbed is wet. The other two roads cannot be decommissioned as they are used to access range improvement. However, limiting their use would help to reduce run-off, erosion, and sedimentation from these roads, improving watershed conditions.
Dry Creek sub-watershed was rated Poor on the watershed condition indicator for Soils. “Poor” soils display significant alteration to reference soil condition, including erosion, productivity, and chemical characteristics, and the overall soil disturbance is characterized as extensive. As the soil condition improves from the proposed vegetation treatments and transportation system actions, this condition indicator would also show improvement.
Like Cienega Creek, the watershed condition indicator for Rangeland Vegetation has been rated Poor for the Dry Creek sub-watershed (table 8). In sub-watersheds that have been rated as “Poor”, the composition of the vegetation has been greatly reduced or unacceptably altered compared to the natural potential of the area. In the Semi-Desert Grassland PNVT, tobosa grass is the most abundant forage for livestock. It is resistant to fire mortality and can sprout and regrow quickly after top-kill by fire and thus could respond well to the proposed wildland fire treatments. Given a sufficient recovery period, the Rangeland Vegetation condition indicator would be expected to benefit from the vegetation treatments on 8,200 acres of this PNVT to reduce shrub and tree cover and allow for an increase in the herbaceous species and annual forb cover.
Little Ash Creek
It could be reasonably concluded that the proposed action would benefit the soil and watershed conditions in this “Functioning Properly” sub-watershed.
Little Ash Creek sub-watershed has about equal percentages of Semi-Desert Grassland (39 percent) and Piñon-Juniper Evergreen Shrub (37 percent) within the TEUIs proposed for treatments.
In the Piñon-Juniper Evergreen Shrub PNVT, TEUI 432, 461, 462, 464, 466, and 491 would be expected to show improvement, but soil conditions would remain in impaired condition due to a pre-existing reduction in soil function. The proposed treatments would alter the overall vegetation structural composition, resulting in an increase of herbaceous cover and an improvement of shrub vigor. In the long-term, this would increase the total vegetative ground cover and improve soil function.
The TEUIs associated with the Semi-Desert Grassland PNVT (TEUI 372 and 373) and the Juniper Grassland PNVT (TEUI 428 and 431) are expected to benefit from the proposed fire treatments. Little to no change in soil loss rates is expected, and treatment would result in a short term improvement to nutrient cycling, plant vigor, and vegetative ground cover. Impaired soil conditions would improve but not change condition class due to a pre-existing reduction of soil function.
Soil conditions for TEUI 479 in the Piñon-Juniper Evergreen Shrub PNVT and TEUI 436, 457, and 551 in the Interior Chaparral PNVT would remain in satisfactory condition because the fire
56 Verde Ranger District, Prescott National Forest treatments are expected to improve vegetation vigor, promote further surface and soil organic matter recruitment, and over the long-term improve soil function resiliency. The Satisfactory soil condition rating for TEUI 430 and 475 would be retained because these units have been identified as “fire avoidance” areas due to their very steep slopes.
Impaired soil conditions for TEUI 485 in the Piñon-Juniper Evergreen Shrub PNVT and TEUI 425 in the Interior Chaparral PNVT would be expected to improve and become satisfactory. Woody cover is currently above TES potential, and decreasing it result in an increase of herbaceous cover and an improvement of shrub vigor. In the long-term, this would increase the total vegetative ground cover and improve soil function.
Impaired and unsatisfactory soil conditions for TEUI 427 and 490 in the Juniper Grassland PNVT would be expected to improve to satisfactory condition. Juniper thinning combined with wildfire treatments would decrease the high juniper cover levels and promote an increase in herbaceous cover. This would improve total vegetative ground cover levels, promote infiltration, and decrease the elevated soil loss rate. Mechanical thinning could result in soil compaction and displacement, however, this would be mitigated through timing restrictions to limit activity to periods when soils are dry and not susceptible to load bearing stresses.
Roads concentrate precipitation run-off and can be a major source of sediment, impacting watershed condition by impacting water quality and quantity. The Poor rating for the Roads and Trails watershed condition indicator (table 8), means that there is a higher probability that the hydrologic conditions have been substantially altered by the roads and trails. These hydrologic conditions include the stream channels and flows, sediment amounts, water quality, and riparian conditions.
The proposed action would decommission two roads within the sub-watershed, FR9601F and FR9601Y. Forest roads FR732, FR9601X, FR9602A, and FR9650R would be subject to seasonal travel restrictions to minimize use when the roadbed is wet and subject to compaction. The decommissioning and removal of these roads from the transportation system would help mitigate impacts on water quality and sediment loads within the sub-watershed.
All or parts of four roads within the sub-watershed – FR9601Z, FR9602C, FR9606E, and FR9650H, totaling about three and a half miles – would be closed to public use. These roads cannot be decommissioned as they are used to access range improvement. However, limiting their use would help to reduce run-off, erosion, and sedimentation from these roads and improve watershed conditions.
Two short roads within the project area that receive a lot of recreation use – FR9602R and FR9650N – would be hardened with an aggregate surface. This is commonly known as “armoring” and is referred to as such in the proposed action. Armoring of these two segments would minimize that erosion and sedimentation that is the result of the heavy recreation use and improve water quality in Little Ash Creek.
Little Ash Creek sub-watershed was rated Poor on the watershed condition indicator for Soils. “Poor” soils display significant alteration to reference soil condition, including erosion,
57 Agua Fria Grasslands Improvement Project productivity, and chemical characteristics, and the overall soil disturbance is characterized as extensive. As the soil condition improves from the proposed vegetation treatments and transportation system actions, this condition indicator would also show improvement.
Lower Ash Creek
It could be reasonably concluded that the proposed action would benefit the soil and watershed conditions in this “Functioning At Risk” sub-watershed.
Most of the Lower Ash Creek sub-watershed (93 percent) is in the Semi-Desert Grassland PNVT. Three of the TEUIs (370, 372, and 373) associated with this PNVT are expected to benefit from the proposed fire treatments. Little to no change in soil loss rates is expected, and treatment would result in a short term improvement to nutrient cycling, plant vigor, and vegetative ground cover. Impaired soil conditions would improve but not change condition class due to a pre- existing reduction of soil function. TEUI 371 is expected to remain in satisfactory condition.
Impaired soil conditions for TEUI 427 in the Juniper Grassland PNVT would be expected to improve to satisfactory condition. Juniper thinning combined with wildfire treatments would decrease the high juniper cover levels and promote an increase in herbaceous cover. This would improve total vegetative ground cover levels, promote infiltration, and decrease the elevated soil loss rate. Mechanical thinning could result in soil compaction and displacement, however, this would be mitigated through timing restrictions to limit activity to periods when soils are dry and not susceptible to load bearing stresses.
Roads concentrate precipitation run-off and can be a major source of sediment impacting watershed condition by impacting water quality and quantity. The Poor rating for the Roads and Trails watershed condition indicator (table 8), means that there is a higher probability that the hydrologic conditions have been substantially altered by the roads and trails. These hydrologic conditions include the stream channels and flows, sediment amounts, water quality, and riparian conditions. The proposed action would decommission two roads within the sub-watershed, FR68C and FR9709C. The decommissioning and removal of these roads from the transportation system would help mitigate impacts on water quality and sediment loads within the sub- watershed.
Lower Ash Creek sub-watershed was rated Poor on the watershed condition indicator for Soils. “Poor” soils display significant alteration to reference soil condition, including erosion, productivity, and chemical characteristics, and the overall soil disturbance is characterized as extensive. As the soil condition improves from the proposed vegetation treatments and transportation system actions, this condition indicator would also show improvement.
The watershed condition indicator for Rangeland Vegetation has been rated Poor for the Lower Ash Creek sub-watershed (table 8). In sub-watersheds that have been rated as “Poor”, the composition of the vegetation has been greatly reduced or unacceptably altered compared to the natural potential of the area. In the Semi-Desert Grassland PNVT, tobosa grass is the most abundant forage for livestock. It is resistant to fire mortality and can sprout and regrow quickly after top-kill by fire and thus could respond well to the proposed wildland fire treatments. Given a
58 Verde Ranger District, Prescott National Forest sufficient recovery period, the Rangeland Vegetation condition indicator would be expected to benefit from the vegetation treatments to reduce shrub and tree cover and allow for an increase in the herbaceous species and annual forb cover.
Little Sycamore Creek
It could be reasonably concluded that the proposed action would benefit the soil and watershed conditions in this “Functioning At Risk” sub-watershed.
Almost 60 percent of the acreage proposed for treatment within the Little Sycamore Creek sub- watershed is associated with TEUIs rated as “Impaired” for soil condition. These are mostly in the in Semi-Desert Grassland (TEUIs 372 and 373; 27 percent), Piñon-Juniper Evergreen Shrub (TEUIs 432, 462, and 464; 25 percent), and Juniper Grasslands (TEUIs 427 and 428; 5 percent) PNVTs. In addition, TEUI 490 in the Juniper Grassland was rated as “Unsatisfactory” for soil conditions.
The TEUIs associated with the Semi-Desert Grassland PNVT (TEUI 372 and 373) and the Juniper Grassland PNVT (TEUI 428 and 431) are expected to benefit from the proposed fire treatments. Little to no change in soil loss rates is expected, and treatment would result in a short term improvement to nutrient cycling, plant vigor, and vegetative ground cover. Impaired soil conditions would improve but not change condition class due to a pre-existing reduction of soil function.
Impaired and unsatisfactory soil conditions for TEUI 427 and 490 in the Juniper Grassland PNVT would be expected to improve to satisfactory condition. Juniper thinning combined with wildfire treatments would decrease the high juniper cover levels and promote an increase in herbaceous cover. This would improve total vegetative ground cover levels, promote infiltration, and decrease the elevated soil loss rate. Mechanical thinning could result in soil compaction and displacement, however, this would be mitigated through timing restrictions to limit activity to periods when soils are dry and not susceptible to load bearing stresses.
Impaired soil conditions for TEUI 485 in the Piñon-Juniper Evergreen Shrub PNVT would be expected to improve and become satisfactory. Woody cover is currently above TES potential and the soil productivity in this TEUI is high. Decreasing the woody species cover would result in an increase of herbaceous cover and an improvement of shrub vigor. In the long-term, this would increase the total vegetative ground cover and improve soil function.
Proposed fire use treatments for TEUI 436 in the Interior Chaparral PNVT would assist in maintaining satisfactory soil conditions by improving shrub vigor in decadent stands and producing additional litter for soil protection. The Satisfactory soil condition rating for TEUI 430 would be retained because these units have been identified as “fire avoidance” areas due to their very steep slopes.
Roads concentrate precipitation run-off and can be a major source of sediment impacting watershed condition by impacting water quality and quantity. The Poor rating for the Roads and Trails watershed condition indicator (table 8), means that there is a higher probability that the hydrologic conditions have been substantially altered by the roads and trails. These hydrologic
59 Agua Fria Grasslands Improvement Project conditions include the stream channels and flows, sediment amounts, water quality, and riparian conditions.
The proposed action would decommission all or part of two roads within the sub-watershed, FR502A and FR9709N. The decommissioning of a section of FR502A has been identified as of particular benefit for soil protection within the sub-watershed. The decommissioning and removal of these roads from the transportation system would help to mitigate their impact on water quality and sediment loads within the sub-watershed.
All or parts of five roads within the sub-watershed – FR68E, FR502A, FR9601L, FR9601N, and FR9606C, totaling about three and a half miles – would be closed to public use. These roads cannot be decommissioned as they are used to access range improvement. However, limiting their use would help reduce run-off, erosion, and sedimentation from these roads and improve watershed conditions.
Little Sycamore Creek sub-watershed was also rated Poor on the watershed condition indicator for Soils. “Poor” soils display significant alteration to reference soil condition, including erosion, productivity, and chemical characteristics, and the overall soil disturbance is characterized as extensive. As the soil condition improves from the proposed vegetation treatments and transportation system actions, this condition indicator would also show improvement.
Sycamore Creek
It could be reasonably concluded that the proposed action would benefit the soil and watershed conditions in this “Functioning At Risk” sub-watershed.
About 45 percent of the acreage proposed for treatment within the Sycamore Creek sub- watershed is associated with TEUIs rated as “Satisfactory” for soil condition, and it was rated “Fair” on the watershed condition indicator for Soils. The 30 percent associated with Impaired conditions are mostly in Piñon-Juniper Evergreen Shrub (TEUIs 432, 461, 462, 464, and 491; 21 percent). The balance of Impaired is in the Semi-Desert Grassland (TEUIs 372 and 373; 3 percent), Interior Chaparral (TEUIs 425 and 457; 3 percent), and Juniper Grasslands (TEUIs 427 and 428; 2 percent) PNVTs. In addition, TEUI 466 in the Piñon-Juniper Evergreen Shrub and TEUI 490 in the Juniper Grassland were both rated as “Unsatisfactory” for soil conditions and combined represent about 12 percent of the treatment acres within the sub-watershed.
In the Piñon-Juniper Evergreen Shrub PNVT, TEUI 432, 461, 462, 464, 466, and 491 would be expected to show improvement, but soil conditions would remain in impaired condition due to a pre-existing reduction in soil function. The proposed treatments would alter the overall vegetation structural composition, resulting in an increase of herbaceous cover and an improvement of shrub vigor. In the long-term, this would increase the total vegetative ground cover and improve soil function.
The TEUIs associated with the Semi-Desert Grassland PNVT (TEUI 372 and 373) and the Juniper Grassland PNVT (TEUI 428 and 431) are expected to benefit from the proposed fire treatments. Little to no change in soil loss rates is expected, and treatment would result in a short term improvement to nutrient cycling, plant vigor, and vegetative ground cover. Impaired soil
60 Verde Ranger District, Prescott National Forest conditions would improve but not change condition class due to a pre-existing reduction of soil function.
Soil conditions for TEUI 479 and 446 in the Piñon-Juniper Evergreen Shrub PNVT and TEUI 436, 448, 457, and 551 in the Interior Chaparral PNVT would remain in satisfactory condition because the fire treatments are expected to improve vegetation vigor, promote further surface and soil organic matter recruitment, and over the long-term improve soil function resiliency. The Satisfactory soil condition rating for TEUI 430 and 475 would be retained because these units have been identified as “fire avoidance” areas due to their very steep slopes.
Impaired soil conditions for TEUI 485 in the Piñon-Juniper Evergreen Shrub PNVT and TEUI 425 in the Interior Chaparral PNVT would be expected to improve and become satisfactory. Woody cover is currently above TES potential, and decreasing it result in an increase of herbaceous cover and an improvement of shrub vigor. In the long-term, this would increase the total vegetative ground cover and improve soil function.
Impaired and unsatisfactory soil conditions for TEUI 427 and 490 in the Juniper Grassland PNVT would be expected to improve to satisfactory condition. Juniper thinning combined with wildfire treatments would decrease the high juniper cover levels and promote an increase in herbaceous cover. This would improve total vegetative ground cover levels, promote infiltration, and decrease the elevated soil loss rate. Mechanical thinning could result in soil compaction and displacement, however, this would be mitigated through timing restrictions to limit activity to p