Metro Clear Creek Canyon Natural Area Upper Bench Restoration Plan. Prepared for Metro By Institute for Applied Ecology

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1 Metro Clear Creek Canyon Natural Area Upper Bench Restoration Plan Prepared for Metro By Institute for Applied Ecology September 2014

2 This document was prepared for Metro by staff at the Institute for Applied Ecology (IAE): Ben Axt The Institute for Applied Ecology is a non-profit 501(c)(3) organization whose mission is to conserve native ecosystems through restoration, research, and education. P.O. Box 2855 Corvallis, OR (541) Please cite this plan as: Institute for Applied Ecology Metro Clear Creek Canyon Natural Area Upper Bench Restoration Plan. 19 pp. All photos by IAE unless otherwise noted. ii

3 Acknowledgements Metro Brian Vaughn Natural Resource Scientist Marsha Holt-Kingsley Plant Material Coordinator Chris Hagel Natural Resource Technician Jeff Merrill - Natural Resource Technician Katy Weil Management Analysis/Wildlife Monitoring Coordinator Ash Creek Forest Management Jason Dumont - Ecologist George Kral Forester Institute for Applied Ecology Guy Banner Natural Resource Technician Tom Kaye Botanist, Executive Director Peter Moore Restoration Ecologist Melanie Gisler Botanist, Program Director Andrew Neil Botanist Larkin Guenther Botanist iii

4 Contents 1 Introduction Project Background Habitats Management Unit Delineation Habitat Goals Habitat Connectivity and Expansion Potential Restoration Strategy Oak Woodlands and Shrub Border Oak Woodland and Shrub Border Restoration Plan Savanna Savanna Restoration Plan Other Considerations Wet Prairie Wet Prairie Restoration Plan Additional Considerations Outreach Schedule Monitoring and Adaptive Management Vegetation Monitoring Wildlife Monitoring Adaptive Management Restoration and Management Challenges Cultural Resources Burning Recreation/Trails Sensitive Species Chemical Limitations Maintenance Future Management Best Management Practices Mowing/Haying Grazing Chemical Treatment Controlling Herbicide Drift Disc/Chisel On-going Maintenance Activities References List of Tables and Figures Figure 1. Restoration units of the Upper Bench Savanna restoration area of CCCNA Table 1. Habitat types at the Upper Bench Savanna restoration area of CCCNA Table 2. Overall project schedule for years 1 and Table 3. Action thresholds for additional maintenance activities iv

5 1.1 Project Background 1 Introduction In November 2013, the Institute for Applied Ecology (IAE) was contracted by Metro to prepare a restoration plan for the Upper Bench Savanna of the Clear Creek Canyon Natural Area (CCCNA). A Site Conservation Plan (SCP)(Metro 2013) provides background for conservation targets and includes specific restoration goals and objectives for habitats within CCCNA. The CCCNA s SCP addresses 551 acres of diverse habitats owned by Metro that have been purchased since While the SCP broadly categorizes the 133 acres of the Upper Bench desired future conditions as savanna, it is recognized that this area, in actuality, will be comprised of a mosaic of habitat types. These include savanna, Oregon white oak (Quercus garryana) woodland, wet prairie, shrub, and conifer forest. This restoration plan augments the SCP by developing the next stage of planning, a restoration and implementation strategy specifically for the Upper Bench Savanna area. The plan is intended to guide the expansion and enhancement of savanna habitat with the goal of increasing the diversity and abundance of native grass and forb species and decreasing the cover of nonnative and invasive species. Restoration will be implemented over many years at CCCNA and management will be ongoing. The SCP proposes to transition the Upper Bench Savanna out of agriculture and restore it to high quality savanna habitat, a process that began in 2010 and is expected to be complete To ensure the site objectives established in the SCP are being addressed, this restoration plan integrates restoration activities with measurable and time bound objectives, long term management considerations, and action thresholds. Techniques, timing, and goals should be re-evaluated and adapted to new conditions as the restoration progresses. Allowing for this flexibility and engaging all restoration partners will allow for informed modifications to the plan and will result in a higher quality product. 1.2 Habitats Management Unit Delineation All habitat types present in the Upper Bench Savanna restoration area are currently undergoing restoration. Restoration units have been defined for this restoration plan using a combination of original condition, desired future condition, and current state of restoration (Table 1, Fig. 1). These units have been labeled with a number followed by a letter (e.g. 1A). The number applies to areas with similar objectives and timing while the letter identifies spatially discrete units. This unit categorization allows restoration planning to occur both at the coarse scale and at finer resolution. 1

6 Figure 1. Restoration units of the Upper Bench Savanna restoration area of CCCNA. 2

7 Table 1. Habitat types at the Upper Bench Savanna restoration area of CCCNA. Habitat Type Unit Acres Subtotal Habitat Type Unit Acres Subtotal Conifer Forest 41.9 Wet Prairie (cont.) 1A 20 Core Prairie 8A 1.6 1B B 1.4 1C 4.1 8C 6.7 1D Core Swale 10A 1.1 Oak Woodland A 2.1 Savanna B 3.7 Savanna 4A B 11.4 Shrub Edges A 2.6 Early Prairie 5A 0.9 3B 4.3 5B 0.8 3C 1 5C 9.9 3D 2 5D 3.3 3E 0.5 5E F 0.8 Wet Prairie G 1.5 Early Wet Prairie 6A B 2.6 Late Prairie 7A C 1 7B 3.4 6D Core Knolls 9A 1.1 continued in next column 9B 1.8 9C Total Habitat Goals The Clear Creek SCP (Section 5.2) outlines the conservation target for the Upper Bench Savanna. Goals for the Upper Bench Savanna conservation target are paraphrased below. Short-term goals Increase diversity of native grass and forb species to greater than 40 species. Expand the area of oak savanna from 100 acres to greater than 120 acres. Decrease the cover of woody tree and shrub cover to less than 20 percent. 3

8 Long-term goal The desired future condition is for key ecological attributes to reach good or very good levels and to provide suitable habitat for prairie and Oregon white oak-dependent wildlife species including native pollinators and ground nesting birds such as western meadowlark. Current Conditions as defined by the SCP (Section 5.2): Key ecological attributes outside normal range of variation Native grass and forb species presence: a limited number of native plant species are present. Canopy cover vegetation structure: trees and shrubs are encroaching into the prairie. Critical threats very high and high range Altered native herbaceous species composition: nonnative species out-compete native grass and forb species. Altered fire regime: fire suppression promotes encroachment of woody shrub and tree vegetation, leading to lack of open structure and conversion to shrub. Altered hydrology: ditches and drain tiles reduce the extent of saturated soils in the wet prairie and emergent wetlands of the savanna areas Habitat Connectivity and Expansion Potential The acres identified for restoration at Upper Bench is only a portion of the habitat designated as savanna at CCCNA. Another 16 acres in the CCCNA separated from the restoration area by pasture on private lands is also designated in the SCP as savanna. If this area were also restored it could add further value to current restoration efforts by limiting weed vectors and increasing resources and habitat connectivity for wildlife. Other potential savanna habitat in the local area that could be enhanced for connectivity is on the Middle Bench of CCCNA as well as on adjacent and nearby private property. 2 Restoration Strategy Work at the Upper Bench Savanna restoration area will continue to focus on restoring agricultural lands, degraded grassland, and forest to create woodland, savanna, and prairie. The strategy for identifying units and reaching desired future conditions combines recommendations from the SCP and expertise of IAE restoration ecologists and other restoration colleagues and partners involved with this project. Knowledge gained from the scheduled monitoring will inform adaptive management and prioritization of restoration and maintenance activities. The plan is intentionally simple and concise, to facilitate efficient and adaptive implementation. Habitat types from Table 1 have been grouped by restoration strategy below. 2.1 Oak Woodlands and Shrub Border Area: The woodland and shrub border areas can be defined in two types: Young oak stands (Unit 2: 5.8 acres) and Shrub edges (Unit 3: 10.4 acres). These two units are combined in this plan because they have similar restoration goals and management recommendations. Baseline Conditions: Young stands of shrubs and trees Dominance of exotic perennial grasses, especially creeping velvetgrass 4

9 Nonnative brush and forbs including nonnative blackberry, hawthorn, and thistles Dense plantings of trees and shrubs on 16.2 acres have been completed in the oak woodland and shrub border areas. Woodland habitats support a variety of bird and insect species that will not be able to utilize the prairie and savanna areas. The shrub border will also provide habitat for species that use forested edges. In addition to the potential habitat values that are provided by these created woodlands, the young stands will mature to create dense cover and prevent growth in the understory. This will create a barrier where herbaceous weed plants will not be able to establish and expand into the prairie and savanna areas. As such, the current plan will focus on maintaining these stands of trees and shrubs as they mature. The three strategies for the woodlands and shrub border are to: Maintain dense stocking to suppress weed encroachment. Control weeds, especially creeping velvetgrass and nonnative brush, while newly planted areas establish. Maintain shrub diversity. Target Habitat: The oak woodlands and shrub borders on the Upper Bench will support a diversity of native trees and shrubs with a sufficiently dense cover able to exclude weeds and provide habitat, both structure and food sources, for wildlife Oak Woodland and Shrub Border Restoration Plan Progress: 16.2 acres have been planted and have not yet formed a closed canopy. Goal 1: Maintain dense stocking and cover of Units 2 and 3. Objective 1: Increase density of shrubs and Oregon white oak to greater than 90% canopy cover. Year 1 (Fall) - Oregon white oak trees removed from wet prairie or savanna (primarily unit 4B) should be used to augment the oak woodland areas by moving with a tree spade. Area should be stocked densely enough to maintain less than 10% absolute herbaceous ground cover after canopy closes. Stems per acre will be reduced as the canopy matures. Herbaceous cover will provide an indicator for appropriate stocking and canopy cover. Census or survey number of shrub and oak trees in Year 3. Focus will be on providing enough vigorous stems to provide closed canopy at maturity. Objective 2: Thin conifers only to increase oak woodland stand vigor. Young Douglas fir trees may need to be selectively thinned if they overtop and cause dieback or self-pruning in oaks. Objective 3: Reduce competition. Control weeds in and around newly planted trees and shrubs. Annually (Spring and Fall) - Assess weed control needs in spring and fall of each year. Apply herbicide to nonnative grasses, especially creeping velvetgrass, with backpack sprayers in and around trees and shrubs to reduce competition for resources and remove weeds on the edges of the prairie as needed while woody species mature. o Avoiding damage to non-target plants must be the highest priority. Treat invasive brush. 5

10 o o Blackberry and other aggressive nonnative shrubs and trees will need to be spot treated annually in the fall while the native species are establishing. As control is established the frequency of treatments may be reduced. Treatments should continue until nonnatives cannot quickly overtop native species (approximately 3-5 years from planting). At this point treatments can continue as dictated by action thresholds (Section 6.6). Goal 2: Maintain diversity. Objective 1: Maintain shrub diversity to increase habitat value for bird and invertebrate pollinators. Annually (Spring) - Monitor shrub diversity and consider augmenting species that have poor establishment. o Replant if failure can be linked to variable conditions (i.e. unusual weather, insect outbreak) o Do not replant a species if failure was due to conditions that are unchanged (i.e. slope aspect, moisture availability). If conditions have not changed, reconsider shrub choices and plant species that are more likely to succeed. Objective 2: Maintain shrub edge to avoid expansion into the prairie. o Monitor for vegetative expansion of shrubs into savanna and wet prairie habitats. o Mow the adjacent savanna and wet prairie areas once a year or every other year as needed. Mowing may be restricted to the leading edge of encroachment unless this treatment is also beneficial to the prairie and savanna. However, the mowing window for the prairie and savanna may be more limited due to potential for disrupting nesting birds or losing the seed crop for flowering native species at certain times of the year. 2.2 Savanna Area: Because of similar management needs, the Savanna management area includes of all of the upland grassland habitats in the restoration unit totaling 55.8 acres. It comprises units 4 (savanna), 5 (early prairie), 7 (late prairie), and 9 (core knolls). Baseline Conditions: Savanna (Unit 4: 12 acres) These areas provide a spatial transition between wet prairie and oak woodland. Savanna is defined as grassland with 3 to 5 trees/acre in the SCP. However, portions of the savanna area have been planted with a much higher density to allow for losses during establishment. The plantings have been very successful and have experienced less mortality than expected. The remaining stocking rate is much higher than is needed to maintain savanna. The understory of the savanna areas is primarily creeping velvetgrass. Control attempts have been ongoing, but success has been limited by treatment options due to the heavy stocking of oaks and shrubs. Unit 4B (11.4 acres) has established oaks and shrubs. The unit has been sprayed with a broad spectrum herbicide to control creeping velvetgrass. A small portion on the western end of the unit has also been disced to prepare the unit for seeding. Unit 4A is a small area that has been cleared of nonnative woody species and its treatments will mirror that of the larger savanna. No oaks have been planted in the area. Early prairie (Unit 5: 18 acres) - The early stage upland prairie restoration fields were dominated primarily with creeping velvetgrass as well as invasive woody species and have received one year of 6

11 management. The restoration plan will combine treatments on these areas with the savanna units to place them on the same restoration timeline. Late prairie (Unit 7: 22.5 acres) The late stage upland prairie restoration former agricultural fields were heavily infested with creeping velvetgrass and are being converted to prairie. After two years of disc and spray treatments the units are nearing the planting stage. Successes and lessons learned on these units will be applied to the remainder of the restoration area. Seed bank testing was completed in August of From each unit 5 samples were taken and homogenized. A subsample from each unit was then taken to the Oregon State University Seed Laboratory for assessment. Both samples contained only low levels Amaranthus sp. Core knolls (Unit 9: 3.3 acres) - The core grassland knolls rise up from the center of the core wet prairie slightly drier soils. This unit has had the same treatment as Unit 8 (core prairie) including spot treatments of weeds and supplemental seeding of native plants. The knolls support less diversity of native species and have a higher cover of nonnative species than other core areas. The primary species of concern on the knolls is oxeye daisy. The goals for the savanna are to: maintain appropriate stocking of woody species, control nonnative species, and plant native prairie forb and graminiod species suited for these savanna habitats. Target Habitat: The savanna areas on the Upper Bench will support a diversity of native forbs, grasses, and woody plants, all providing habitat for wildlife including native grassland birds, butterflies, reptiles, and amphibians. Matrix species of bunchgrasses and forbs will be the dominant species and provide habitat stability Savanna Restoration Plan Goal 1: Maintain appropriate oak and shrub density in Unit 4. Objective 1: Reduce density to three clumps of two trees per acre. Year 1 (Fall): Remove oaks to reduce density to 66 total trees in unit 4B. o Use a tree spade to move up to 50 trees. Removed trees will be used to augment the adjacent woodland areas. o Cut, remove stems, and treat stumps of remaining surplus oaks to reach target densities. o o Remaining trees should be selected for vigor and growth form. Remaining trees should be spatially arranged to enable broadcast treatments. Retain the ability to treat with a 30ft boom sprayer including allowing for turning radius. Year 1 (Fall): Remove shrubs and treat cut stumps to reduce the number of shrub patches by 50%. Spatial arrangements should follow those outlined in the previous bullet. Objective 2: Protect remaining trees. Soil disturbing activities, such as discing, will be avoided under the drip line of oaks. Allow recruitment of additional oak trees after savanna understory is established. o Expected to be approximately two new saplings established in unit 4B every 10 years (to allow complete stand replacement in 115 years). Accomplished by protecting selected natural seedlings or planting and protecting larger nursery stock. 7

12 o Identify trees to protect and mark them clearly. Avoid equipment use within drip line of preserved trees. Provides a variety of age classes that will result in a diverse structure and maximum habitat value. Goal 2: Enhance native prairie and savanna habitat in Units 4 and 5. Objective 1: Control aggressive invasive weeds. Year 1, Year 2 (Spring and Fall): Disc and broadcast spray creeping velvetgrass as this treatment has been successful in the past. o Avoid damage to non-target plants by using a backpack sprayer around oaks. o Mortality of less than 75% shrub cover is acceptable if needed to control creeping velvetgrass. o Timeline may be accelerated or delayed based on the progress within this objective. Objective 2: Establish native herbaceous species. Year 2 (Summer): Seed bank testing. o Accomplished by gathering at least 5 samples of top soil approximately 3 inches in diameter and 4 inches deep from each unit of interest. o The soil from each block will be sent to the OSU Seed Laboratory for testing. o The process will provide assurance of weed free zones and help to actively plan for future management actions. Year 2 (Fall): Broadcast and roll native herbaceous species to ensure proper planting depth for forb seed while providing soil contact for seeds. Seed list to be determined by March of Year 2. o Proceed if seed bank levels of weedy species will not threaten native establishment. o Broadcast seed with tractor or ATV pull behind spreader. o Follow with tractor or ATV mounted roller. o Plant plug, bulbs and bare root stock when available. Objective 3: Maintain native cover. Year 3 (Spring, Summer, Fall) Monitor success of planting qualitatively. o Gauge native seedling establishment. Should be of sufficient density of natives to shade competition at maturity. Observe individual species establishment. Note approximate relative cover of each. Compare relative cover to the intended species composition presented in planting plan. o Monitor for weed establishment. Monitor for weed establishment by recording weed species, locations, and densities. These will then be compared with established action thresholds to determine a course for treatment. Accurate weed records will help to improve efficiency treatment implementation by reducing relocation and reassessing of weed populations. Compare populations with established action thresholds. Year 3 (Fall) Use areas of poor establishment to enhance diversity. o Areas where initial seeding is unsuccessful can be used to introduce species that were not included in the original seed mix. 8

13 Identify areas that have poor seedling establishment. Select appropriate species for site conditions. Broadcast at high rate to ensure establishment. o Technique can be applied to areas that have been treated with broad spectrum herbicide to control priority weeds. Monitor for weed problems focusing on early detection of weed species with a rapid response to high priority weeds. Goal 3: Restore prairie vegetation and its ecological processes to provide habitat for native wildlife in Unit 7. Objective 1: Control aggressive invasive weeds. (Completed 2014) Year 1 (Spring): Disc and broadcast spray of creeping velvetgrass. Objective 2: Establish native herbaceous species. Year 1 (Summer): Seed bank testing. (Completed 2014) o Accomplished by gathering at least 5 samples of top soil approximately 3 inches in diameter and 4 inches deep from each unit of interest. o The soil from each block will be sent to the OSU Seed Laboratory for testing. o The process will provide assurance of weed free zones and help to actively plan for future management actions. Year 1 (Summer/Fall): Treatment of aggressive weeds. (Completed 2014) Year 1 (Fall): Broadcast and roll native herbaceous species. o Proceed if seed bank levels of weedy species will not threaten native establishment. o Broadcast seed with tractor or ATV pull behind spreader. o Follow with tractor or ATV mounted roller. Objective 3: Maintain native cover. Year 2 (Spring, Summer, Fall) Monitor success of planting qualitatively. o o o o Gauge seedling establishment. Should be of sufficient density of natives to shade competition at maturity. Observe individual species establishment. Note approximate relative cover of each. Compare relative cover to the intended species composition. Monitor for weed establishment by making note of weed species, locations, and densities. These will then be compared with established action thresholds to determine a course for treatment. Accurate weed records will help to improve efficiency treatment implementation by reducing relocation and reassessing of weed populations. Year 2 (Fall) Use areas of poor establishment to enhance diversity. o Areas where initial seeding is unsuccessful can be used to introduce species that were not included in the original seed mix. Identify areas that have poor seedling establishment. Select appropriate species for site conditions from the seeding list. Broadcast at high rate to ensure establishment. o Technique can be applied to areas that have been treated with broad spectrum herbicide to control priority weeds. o Plant plug, bulb, and bare root stock when available. Monitor for weed problems focusing on early detection of weed species with a rapid response to high priority weeds. 9

14 Goal 4: Create a comprehensive plant lists for all units to inform future management. Objective 1: Determine species present at the site. IAE has added to the current plant list created by Metro by surveying the site twice in the spring/summer of Attention was primarily focused on areas that supported diverse plant communities. This effort is expected to be nearly comprehensive. However, plant lists can be updated by all managers as they engage in activities on the site. Goal 5: Design restoration strategy consistent with current plant populations in Unit 9. Ash Creek Forestry will design a strategy for reducing oxeye daisy in the unit to be included in the scheduled update of this plan. Restoration and planting schematic will evolve from strategies needed to control oxeye daisy. o Reintroduction of native populations disturbed by control efforts will be needed. o Augmentation through seeding and planting of native plant materials will encourage successful restoration following oxeye daisy control. o Will be outlined in plan revision scheduled for Year Other Considerations The conifer trees in the center of unit 7A (Savanna: Late Prairie) are a considerable barrier to the utilization of this habitat by grassland birds, such as western meadowlark. These trees are scheduled to be removed in the fall of Wet Prairie Area: The wet prairie includes areas of depression wetlands and a swale surrounding an intermittent stream (19.6 acres). The early stage wet prairie restoration areas include 8.8 acres, delineated as map unit 6. While these units are discrete on the map, the borders between units should be treated as transitional areas for the purposes of plant selection and management. The early wet prairie category contains areas that have not received site treatment and those with one year of management. The restoration of these areas closely follows savanna units 4 and 5. Baseline conditions: The core prairie (Unit 8, 9.7 acres) and swale (1.1 acres) areas contain the highest quality habitat on the Upper Bench Savanna. The core prairie is a remnant prairie that has received seeding with native species and several targeted herbicide treatments. The prairie and swale support a high diversity of native species that are continually threatened by nonnative grasses and forbs also thriving here. Restoration activities will focus on maintaining the core native plant community and enhancing diversity. Target Habitat: The wet prairie on the Upper Bench will support a diversity of native native forbs and grasses providing habitat for wildlife including native grassland birds, butterflies, reptiles, and amphibians. Matrix species of bunchgrasses and forbs will be the dominant species and provide habitat stability. 10

15 2.3.0 Wet Prairie Restoration Plan Goal 1: Create a comprehensive plant list to inform future management. See Section 2.2.1, Goal 4, Objective 1. Goal 2: Restore prairie vegetation and its ecological processes to provide native habitat in Unit 6. Restoration of Unit 6 will be concurrent with efforts listed for restoration of Units 4 and 5 outlined in Section Goal 2. Goal 3: Maintain prairie vegetation and its ecological processes to provide habitat for native wildlife while contributing to the biodiversity and functionality of the watershed (Units 8 and 10). Objective 1: Reduce nonnative grasses to prevent competition with native species. o Year 2 and 3 (Spring/Fall): Spot spray of grass specific herbicide to reduce nonnative grass. o Plant native diversity behind areas receiving extensive treatments. When larger areas of grass removal occur, it opens up an opportunity to introduce greater native plant diversity in these patches. Planting lists can guide species selection for a follow up seeding or planting. o Consider broadcast treatment with grass specific herbicide. Removing all grasses from the area will allow for only native grasses to be drilled into the area in subsequent years. This can result in much less time investment in the long term. Objective 2: Reduce cover of nonnative forb species competitive enough to affect vigor of native species (e.g. oxeye daisy and tansy ragwort). Continue targeted spot spraying treatments for these species Additional Considerations If flame-weeding is implemented, consider following with a broadcast spray of a broad-spectrum herbicide such as glyphosate. Invasive species including oxeye daisy, tansy ragwort, and false dandelion are the first to re-sprout following a burn. This creates a window of opportunity to treat these invasive species without harming natives. The wet prairie of the Upper Savanna Bench has the potential to function in the future as a recovery site for threatened and endangered plant species of the Willamette Valley such as Nelson s checkermallow (Sidalcea nelsoniana) and Bradshaw s lomatium (Lomatium bradshawii). Introduction of these rare plants should be considered only after the prairie plant community is stable and predominantly native. Timing and introductions and selection of species should be guided by habitat conditions, such as hydrology, recovery goals, and plant material availability. The swale running through unit 6A appears to have been artificially deepened. This has caused altered hydrology east across the unit to the road. Feasibility of restoring this hydrology should be considered before planting plans are finalized for the affected areas. IAE could assist in investigating the feasibility and potential funding of this hydrological restoration if required. Unit 6B will have had a test spot treatment with a broad spectrum herbicide in The intent is to remove the dominant cover of nonnative grasses to release unexpressed native species. If native species have a positive response to this treatment, discing is not advisable. 6B will then need to be treated as core prairie. If native species response to herbicide treatments is minimal or absent, the area can be treated as outlined above in Section Goal 2. 11

16 3 Outreach Clear Creek Canyon Natural Area s SCP highlights the need for outreach and engaging the public. Many opportunities exist for involving the public in the restoration process. The resulting natural area will also create a diverse set of resources to engage visitors. Goal 1: Provide public recreational and educational opportunities for viewing wildflowers, grassland birds, mammals, reptiles, and amphibians. Objective 1: Coordinate restoration efforts with public trail system. Design trail system through restoration area that provides viewing opportunities, but limits ecological impact. Consider signage that illustrates the habitat restoration process and describes target habitats and species to benefit. Work to incorporate volunteers into restoration work. Tasks that are well suited to volunteers are planting, seed collection, light weeding, and monitoring (for qualified volunteers). Objective 2: Collaborate with K-12 education programs about habitat restoration. Coordinate with ecological education programs to provide field work days and field trips. Designate an area of habitat where students will receive hands-on habitat restoration experience through planting native species. Give students hands-on habitat restoration experience through growing and planting rare native prairie species, as age appropriate. Where possible, use students in monitoring tasks. 12

17 4 Schedule Table 2. Overall project schedule for years 1 and 2. Precise timing may vary with site access, weather conditions, and adaptive management. Year 1 Year 2 Activity Units S O N D J F M A M J J A S O N D Weed and planting assessments All X X X Move oaks and shrubs with tree spade Broadcast herbicide treatment with glyphosate to reduce nonnative understory Broadcast herbicide treatment with glyphosate to reduce nonnative understory 1A; 2B; 3A; 4B X 1;2;3;4;5;6A,C,D X X X X 7 X Spot treatment of nonnative weeds in high quality areas 6B; 8, 9, 10 X X X X Grass specific treatment 8, 10 X X Discing 4;5;6A,C,D X X Seeding/Planting 4;5;6A,C,D X X Seeding 7 X X Planting 7 X X Seed bank testing 4;5;6A,C,D X *6B is unaccounted for in most of schedule. See above plan for management actions. 13

18 5 Monitoring and Adaptive Management Monitoring will occur to: Locate and map invasive species and assess success of invasive species control efforts. Evaluate the establishment rates of plantings and the intensity of wildlife browse to plantings. Assess the effects of habitat restoration, management and enhancement tools (e.g., mowing, grazing) on plant community composition (Section 5.1). Track breeding bird response to restoration activities Inform adaptive management. Vegetation Monitoring Informal monitoring to assess weed control issues, chemical treatment effectiveness and seeding establishment should occur at least twice a year. Formal monitoring methods will vary between habitat types. Wildlife Monitoring Existing data from bird surveys will be used as baseline for species presence. Repeat surveys, utilizing the same methodology, are recommended every 3 to 5 years. Students may assist with various scales and levels of monitoring for insects, amphibians, and reptiles. Data from student projects would, at minimum, indicate species presence. Adaptive Management Adaptive management is a process that allows land managers and restoration practitioners to incorporate new information in their practices as it becomes available. Information learned from longterm monitoring is especially useful to modify management at a site and help reach project goals. Upland prairie restoration is a relatively novel process, and new information is constantly being acquired. Creeping velvetgrass is fairly uncommon in Willamette Valley restoration sites and information gained from management at CCCNA will inform control at other sites with this weed and prevent its spread through the region. The schedule and techniques presented in this plan may be modified through the adaptive management process. Monitoring results will be reviewed as monitoring is completed, and used to modify upcoming management processes. Examples may include, but are not limited to: If a flush of a new weed species arises following discing, additional spot spray may be required and application of additional native cover crop. If prairie species establish poorly from seed, restoration plan may be modified to add additional site preparation for future plantings, and planting plugs may be considered. If thatch builds more slowly than expected the plan schedule may be modified to delay the maintenance regime. If flooding causes poor seed establishment in the swales, planting of divisions, bulbs, and plugs may be considered in areas of limited success. If Unit 6B does not dry enough to provide equipment access and the spray tests do not show the presence of high quality native species, convert the area to shrub plantings to ease management concerns. 14

19 6 Restoration and Management Challenges A variety of challenges will be provided by the location and nature of Clear Creek Canyon Natural Area restoration project. They are outlined here to provide the context for restoration activities. Cultural Resources As the majority of the property has been under cultivation for many years, it has already experienced significant ground disturbance. Any archaeological sites that are identified will be avoided during restoration. Burning While an extremely effective habitat restoration tool, prescribed burning may be challenging at CCCNA due to site conditions and its proximity to Portland area. A flame-weeder should be considered to mimic fire when needed. Flame-weeding will reduce concern about safety and simplify burn plans. Prescribed grazing is also an acceptable alternative to burning. A grazing plan will allow for appropriate grazing to achieve desired goals. Recreation/Trails Metro plans to develop trails that will promote passive recreation at CCCNA. This will provide opportunities for interpretive signs or other educational materials with information about habitat restoration. Trail locations may be able to complement restoration by providing a border that can serve as a fire break and weed barrier. Foot traffic that is confined to trails should not threaten sensitive plant or wildlife species. There may be times when public access may need to be diverted, such as during herbicide treatment. Restrictions on dog access should also be considered to protect wildlife species, particularly during the nesting season for grassland birds. Sensitive Species As areas of the Upper Bench area become more stable and diverse, rare species introductions may be considered. Acquisition of rare plant materials (seeds or transplants) can be challenging but is possible with advanced planning and coordination with the US Department of Agriculture s Natural Resources Conservation Service (NRCS) Plant Materials Center (PMC) or qualified native seed producers such as Heritage Seedlings and permitting agencies. Institute for Applied Ecology is producing plant materials that may also contribute to this effort. Plant material selection should follow guidelines of provenance and seed source in the USFWS Recovery Plan for Prairie Species of Western Oregon and Southwest Washington (USFWS 2010b). Chemical Limitations All herbicides used in restoration activities will be used within the guidelines of their labeling, particularly relative to required setbacks from water courses. Suggested Integrated Pest Management (IPM) guidelines specific to the species at CCCNA are included in the Metro IPM and relevant USFWS- NOAA Biological Opinions for fish species (National Marine Fisheries Service 2009). Maintenance Maintenance is a priority on the Upper Bench during and after restoration is complete. Maintenance activities will include invasive weed control and regular mowing and supplemental plantings as needed (Table 2). 15

20 Table 3. Action thresholds for additional maintenance activities. Action Thresholds All targets are relative cover per management unit unless otherwise noted. All targets are intended to guide maintenance actions. Weed control measures during establishment are addressed above. Targets listed in order of priority of treatment. Target Symptom Areas of Highest Concern > 80% native cover Poor seedling All. Highest likelihood establishment of failures will be small areas differing from their surroundings. > 40 native herbaceous species present on site Encroachment of aggressive exotic species Selected diversity species did not survive over time. 0% cover of new noxious weeds Seed or plant materials vectored to the site. < 15% cover of oxeye daisy Throughout Units 4, 5, 7, and 9 < 10% cover of nonnative blackberry < 5% cover of creeping velvetgrass All All All All. Highest likely hood of colonization edges and under trees and shrubs. Throughout Units 4, 5, 7, and 9; May also be a minor concern in units 6, 8, and 10. Solution Reseed areas after examining planting techniques and seed list. Consider grow out for species that did not establish. See below for individual species. Examine plant selection. Either replant the species in different areas or interplant with different species that are expected to success and fill the same ecological niche. Rapid response to eliminate small unestablished populations. Treat according to IPM. Reseed appropriate seed into large disturbance areas. Treat according to IPM. Reseed appropriate seed into large disturbance areas. Treat according to IPM. Reseed appropriate seed into large disturbance areas. < 10% cover of false dandelion Drier areas. Treat according to IPM. Reseed appropriate seed into large disturbance areas. < 10% cover of tansy ragwort All Reseed appropriate seed into large disturbance areas. Do not use chemical control if cinnabar moth (biological control) is present. 16

21 <20% absolute thatch cover Dead vegetation is allowed to accumulate on site All Amend fire, haying, or grazing regime to be more aggressive. 7 Future Management Best Management Practices The following best management practices include those recommended by the U.S. Fish and Wildlife Service for use in areas with sensitive species of the Willamette Valley in the programmatic formal consultation on Western Oregon prairie restoration (USFWS 2008) and the USFWS programmatic restoration biological opinion for the Partners for Wildlife Program (USFWS 2010a). Following best management practices will help to avoid damaging rare resources. 7.1 Mowing/Haying Mowing and haying shall be completed to reduce competition from introduced perennial grasses and shrubs, and will occur under the following limitations: Mowing may be conducted throughout the site after grassland bird nesting season and rare plants have senesced and before they re-emerge the following spring (generally August 15 March 1). Haying may also be completed in this timeframe, but should not be used over rare plants (if introduced) unless loss of seed from the previous season is acceptable. 7.2 Grazing The area grazed in any given year at each site will be determined yearly based on individual site conditions and habitat needs. Targeted management of stock will provide thatch reduction or individual species control while maintaining native species diversity. Summer and fall grazing are generally most effective at reducing thatch and nonnative species while maintaining natives. Appropriate barriers will be used to contain stock. Stock species selection will be guided by management objective. Stocking rates will be designed to accomplish specific goals (e.g. 80% reduction of thatch in 1week). Stock must be given a weed free feed rest before being moved on site. Seeds can pass through ruminant digestive tracts and remain viable. Standing water and wet soils will not be grazed to limit soil disturbance. 7.3 Chemical Treatment Chemical treatments may be used to control aggressive exotic species for which manual control is not logistically efficient or has not proven successful. Herbicides will be applied by a licensed applicator, using appropriate equipment and best management practices. Exposure of non-targeted species to herbicides associated with drift, leaching to groundwater, and surface runoff will be avoided or minimized. Chemical treatments will follow labeled restrictions, including limitations for use near water. 7.4 Controlling Herbicide Drift The following procedures will be used to control herbicide drift: 17

22 The lowest effective nozzle pressure and minimum effective nozzle height recommended by the nozzle manufacturer will be used. Droplet size shall be at least 500 microns. Spraying will not occur where winds exceed the wind limits specified by the manufacturer and in no event shall winds exceed 11 km (7 mi) per hour. Spraying shall occur when temperatures are below 30 C (85 F). Drift retardant adjuvants may only be used for boom spray applications and must be nontoxic. Dyes may be used for applications to ensure complete and uniform application and to observe the amount of drift. 7.5 Disc/Chisel The following procedure will be used to ensure proper implementation of soil disturbing techniques: All areas treated will be included in a comprehensive plan. No areas will be treated that have sensitive habitat. Soil disturbance techniques will not be used where soil has no history of disturbance. On-going Maintenance Activities Primary maintenance activities in the restoration area, in Year 4 (expected to be 2017) and beyond, will include mowing, haying or grazing, removal of encroaching conifers, and control of invasive species. The best management practices described above (Section 7.1) should be followed. General maintenance activities will include the following: Fall mowing, haying, or prescribed grazing of the prairie and savanna will occur each year to reduce competition for native species and minimize tree and woody shrub species encroachment into the prairie. These activities should only occur on 1/3 of the entire site area in any given year. This will result in a three year disturbance interval for any given area which will allow refugia for plants and animals. Any small conifers that are not eliminated through mowing or fire should be removed annually. The edges will be the primary area of concern for conifers. Weed control will need to be ongoing. Searches for new exotic species and spot-spraying with herbicide should occur on a regular basis. Weed surveys should be completed twice yearly to inform control efforts. Any areas of bare soil created through tree removal, weed control, or other disturbance should be seeded in September or October using the species designated for the habitat in the seeding list. These tasks will be able to be more accurately targeted to individual units at the end of the restoration phase. At that point, needs for the individual areas will be more apparent and a more reliable management guide can be created. 18

23 8 References National Marine Fisheries Service Programmatic Biological and Conference Opinion and Magnuson-Stevens Fishery Conservation and Management Act Essential Fish Habitat Consultation for restoration actions funded or carried Out by the U.S. Fish and Wildlife Service in Oregon and Southwest Washington using the Partners for Fish and Wildlife, Coastal, and Recovery Programs. NMFS No. 2008/03791, National Oceanic and Atmospheric Administration, Seattle, Washington. 101 pp. Metro Clear Creek Canyon Natural Area: Site Conservation Plan. 26 pp plus maps and appendicies. 19