Appendix A3 Santa Clara Watershed EA _Invasive_Plant_Treatment_Project_EA.pdf

United States Department of Agriculture

Forest Service

June 2013

Environmental Assessment

Invasive Plant Treatment Project

Santa Clara/Mojave Rivers Ranger District, Angeles National Forest Los Angeles County, California

Portions of T3N, R14, 15W; T4N, R11, 12, 13, 14W; T5N, R13, 14, 15, 16, 17W; T6N, R13, 14, 15, 16, 17W; T7N, R14, 15, 16, 17, 18W, SBM in Los Angeles County, California

For Information, Contact Tasha Hernandez

33708 Crown Valley Road

Acton, CA 93510 http://www.fs.fed.us/r5/angeles/projects/

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Civil Rights, 1400 Independence Avenue, S.W., Washington, D.C. 20250-9410, or call (800) 795-3272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider and employer.

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project iii

Table of Contents Chapter 1 - Introduction

Chapter 2 - Alternatives, including the Proposed Action

Design Features………………………………………………………………………………..27

Chapter 3 - Affected Environment and Environmental Consequences

Human Health and Safety……………………………………………………………………..43

Invasive Plants and Native Vegetation

Special Status Plants

Wildlife

Soils and Water

Wilderness

Recreation and Scenic Resources

Consequences Relative to Significance

Chapter 4 – List of agencies and persons consulted

References

Appendix A Summary of Public Comments

Appendix B Additional Invasive Plant information

Appendix C Potential Treatment Prescription Options

List of Figures Figure 1. Project area map west

Figure 2. Project area map east....................................................... Error! Bookmark not defined.

Figure 3. Subwatersheds west

Figure 4. Subwatersheds east

List of Tables

Table 1. List of high and moderate priority invasive plants

Table 2. Summary of treatment methods proposed

Table 3. Summary of range of and typical application rates for each herbicide proposed

Table 4. Herbicides considered for use, including examples of trade names, and how they affect plants

Table 5. Miles and acres by by subwatershed

Table 6. Summary comparison of alternatives

Table 7. Summary of hazard indicators and toxicity categories for pesticides

Table 8. Signal Word used for each acute toxicity category…

Table 9. Rating of risk to human health and safety for each herbicide and adjuvants (in general) considered in alternative 1

Table 10. Approximate acres by vegetation type within project area

Table 11. Highlighted specific toxicities to plants by herbicide

Table 12. Herbicide Behavior in the Environment

Table 13. Summary of Public Comments………………………………………………….……101 iv

Table 14. Invasive plants known to occur in and near the project area. Cal-IPC inventory categories, CDFA ratings, and the Santa Clara/Mojave Rivers Ranger District

(SCMRRD) priority

Table 15. High and moderate priority species reproductive mechanisms that have been identified

(Warner et al. 2003)

Table 16. Dispersal vectors for high and moderate priority invasive plants

Table 17. Vegetation type high and moderate priority invasive plant species are known to occur in

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project

CHAPTER 1 - INTRODUCTION

Background _____________________________________

Since the earliest days of human development and settlement, plant species have been spread into areas where they do not naturally grow. Beginning in the 1970’s several Executive Orders were issued and laws passed to prevent further harm from these invasive non-native species and institute programs to correct damages already inflicted. The 2005 ANF Land Management Plan (LMP) further acknowledged that many of these species can damage and reduce the function of native ecosystems.

The Angeles National Forest Land Management Plan (Forest Plan) states, “….some of the greatest threats to riparian and aquatic habitats is from the invasion of non-native plant species, particularly tamarisk, arundo, and cape ivy within the stream channels….” (Forest Plan, part 1, p. 41; USFS

2005). The desired conditions for the project area are to have structure, function, and composition of plant communities and wildlife habitat unimpaired by the presence of invasive non-native plants

(Forest Plan, part 1, p. 32; USFS 2005); to have the watercourses functioning properly with riparian vegetation consisting primarily of native species, with minimal or no presence of invasive non-native plants (Forest Plan, part 1, p. 41; USFS 2005); and to reduce and control exotic species over time to restore healthy riparian systems (Forest Plan, part 2, pp. 42, 66; USFS 2005).

Appendix M, Part 3 of the Forest Plan provides detailed strategy and direction on working with partners to achieve invasive species goals across the entire watershed. The proposed project is consistent with the various goals, objectives, and strategies outlined in the LMP. (Forest Plan, part 3,

pp. 121-130; USFS 2005).The Forest Plan (USFS 2005) has goals to reverse the trend of increasing loss of natural resource values due to invasive species (Goal 2.1), retain a natural evolving character within wilderness (Goal 3.2), improve watershed conditions through cooperative management (Goal

5.1), improve riparian conditions (Goal 5.2), and provide ecological conditions to sustain viable populations of native and desired non-native species (Goal 6.2). The Forest Plan Weed Management

Strategy (appendix M in the Forest Plan, part 3) includes coordinating with the Los Angeles Weed

Management Area (WMA) to continue controlling and/or removing German and English Ivy, Vinca, and Spanish broom in Bouquet Canyon; yellow star-thistle on the Santa Clara/Mojave Rivers Ranger

District; distaff thistle in San Francisquito, Bouquet and Soledad Canyon. Appendix M also directs the Forest to coordinate with the State of California for tamarisk removal in upper Castaic Creek.

Appendix M Part 3 also includes coordinating with the Los Angeles WMA to monitor status of halogeton along California State Highway 14 near national forest boundary, perennial pepperweed in the Santa Clara River near the National forest boundary, and apiary sites for yellow star-thistle, spotted knapweed, and other invasive plants.

Forest Service Manual direction for Invasive Species Management is contained in a new manual section, FSM 2900, effective December 5, 2011. This direction sets forth National Forest System policy, responsibilities, and direction for the prevention, detection, control, and restoration of effects from aquatic and terrestrial invasive species (including vertebrates, invertebrates, plants, and pathogens). This new chapter replaces FSM 2080 (Noxious Weed Management). Some of the policy direction found in FSM 2900 that is most related to this project is excerpted below:

• Initiate, coordinate, and sustain actions to prevent, control, and eliminate priority infestations of invasive species in aquatic and terrestrial areas of the National Forest System using an integrated pest management approach, and collaborate with stakeholders to implement cooperative invasive species management activities in accordance with law and policy.

• Ensure that all Forest Service management activities are designed to minimize or eliminate the possibility of establishment or spread of invasive species on the National Forest System, or to adjacent areas. Integrate visitor use strategies with invasive species management activities on aquatic and terrestrial areas of the National Forest System. At no time are invasive species to be promoted or used in site restoration or re-vegetation work, watershed rehabilitation projects, planted for bio-fuels production, or other management activities on national forests and grasslands.

• Use contract and permit clauses to require that the activities of contractors and permittees are conducted to prevent and control the introduction, establishment, and spread of aquatic and terrestrial invasive species. For example, where determined to be appropriate, use agreement clauses to require contractors or permittees to meet Forest Service-approved vehicle and equipment cleaning requirements/standards prior to using the vehicle or equipment in the

National Forest System.

• Monitor all management activities for potential spread or establishment of invasive species in aquatic and terrestrial areas of the National Forest System.

• Manage invasive species in aquatic and terrestrial areas of the National Forest System using an integrated pest management approach to achieve the goals and objectives identified in

Forest Land and Resource Management plans, and other Forest Service planning documents, and other plans developed in cooperation with external partners for the management of natural or cultural resources.

• Develop and utilize site-based and species-based risk assessments to prioritize the management of invasive species infestations in aquatic and terrestrial areas of the National

Forest System. Where appropriate, use a structured decision making process and adaptive management or similar strategies to help identify and prioritize invasive species management approaches and actions.

• Establish and maintain a national record keeping database system for the collection and reporting of information related to invasive species infestations and management activities, including invasive species management performance, associated with the National Forest

System. Require all information associated with the National Forest System invasive species management (including inventories, surveys, and treatments) to be collected, recorded, and reported consistent with national program protocols, rules, and standards.

• Where appropriate, integrate invasive species management activities, such as inventory, survey, treatment, prevention, monitoring, and so forth, into the National Forest System management programs. Use inventory and treatment information to help set priorities and select integrated management actions to address new or expanding invasive species infestations in aquatic and terrestrial areas of the National Forest System.

• Assist and promote cooperative efforts with internal and external partners, including private, State, tribal, and local entities, research organizations, and international groups to collaboratively address priority invasive species issues affecting the National Forest System.

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project

• As appropriate, collaborate and coordinate with adjacent landowners and other stakeholders to improve invasive species management effectiveness across the landscape. Encourage cooperative partnerships to address invasive species threats within a broad geographical area.

The Santa Clara River has been severely degraded by invasive, nonnative plants which have increased over time. In 2006, The Upper Santa Clara River Watershed Arundo/Tamarisk Removal Plan

(SCARP) and EIR were completed by the Ventura County Resource Conservation District and dozens of federal, state and local cooperators. The Forest Service was a cooperator, but needed to complete

National Environmental Policy Act (NEPA) compliance to treat invasive species on National Forest

System lands before on-the-ground projects could be completed. Subsequent to the SCARP, the

Santa Clara River Invasive Plant Removal Project (SCIPR) was started, and now the entire Santa

Clara River Watershed is, or will be, covered from the headwaters to the coast. Projects are being implemented downstream of the National Forest, but the long term success in controlling invasives in the entire watershed will be dependent on the ability of the upstream landowners, like the Forest

Service, to control invasive plants in the headwaters. The California Department of Fish and Game

(CDFG), U.S. Fish and Wildlife Service (USFWS), and the state and federal water management agencies are all partners in this Santa Clara River restoration effort, and these groups have expressed support for the Forest Service treating invasive plants in the upper watershed.

The Santa Clara/Mojave Rivers Ranger District implemented an arundo (Arundo donax) eradication project between 1995 and 2005 in Soledad Canyon and San Francisquito Canyon. Arundo is a destructive pest affecting all of the large river systems in southern California. The District has been successful in controlling population expansion at treatment sites, but other invasive plant species, such as tamarisk and tree-of-heaven, have become established. Some arundo is beginning to show up in small amounts in the treated areas once again. The original decision to treat arundo is over 15 years old. The purpose of this environmental assessment is to update and expand the original project’s purpose and need, project area, and approved treatment activities.

Purpose and Need for Action

If the invasive species are left unchecked, the ecosystem in this watershed could be dramatically changed. Invasive plants could create a host of adverse environmental effects, including:

displacement and loss of native plants; alteration of the hydrology of riparian habitat, reduction in habitat and forage for wildlife (including threatened, endangered, and sensitive species); reduction in water quantity; potential reduction in soil productivity; and potential increases in the intensity and frequency of wildland fires. After wildland fires in this area, non-native plant species typically re-establish more rapidly than native plants, suppressing the recovery of the native vegetation and allowing the invasive plants to expand their range. In addition, when wildland fires occur too frequently (tamarisk and arundo-dominated communities experience higher fire frequencies than native riparian communities), some of the native vegetation lose the ability to recover, effectively converting high diversity native plant communities into low diversity non-native communities.

Based on national, agency, and Forest direction, the needs for this project are to:

• Eradicate, control, contain, and/or suppress existing invasive plant species in the Santa

Clara River and its tributaries from the Forest boundary to the headwaters.

1 Eradicate is to totally eliminate an invasive plant species from the project area; control is to reduce the infestation over time but some level of infestation may be acceptable; contain is to prevent the spread of the invasive plants beyond the perimeter of patches or infestations presently existing; and, suppress is to prevent seed production throughout the target patch and reduce the area coverage, preventing the invasive species from dominating the vegetation in the area where low levels may be acceptable.

• Provide for aggressive treatment of new infestations of invasive plants (in terms of new areas and new species) to allow for rapid treatment and containment of small infestations before they become established.

• Focus on invasive plant species that are classified as undesirable, noxious, harmful, injurious, or poisonous, including but not limited to State listed high priority noxious weeds (such as arundo, tamarisk, and tree-of-heaven).

• Cooperate with state and county agencies and private landowners interested in managing invasive plants within the project area.

In meeting the needs for action, the following purposes (objectives) will be achieved:

• Improve riparian habitat, aquatic conditions, and the overall quality and quantity of water.

• Contain and/or eradicate highly flammable and fire-adapted invasive plant species (e.g.

arundo, tamarisk) that have the potential to increase fire severity and increase the frequency in occurrence of damaging wildfires in these drainages.

• Minimize adverse impacts from the project to populations of threatened, endangered, and/or Forest Service sensitive plant and wildlife species.

• Minimize adverse impacts to the native riparian and upland vegetation within the project area.

• Provide for health and safety during implementation of the project to nearby residents, forest visitors, and project implementers.

Decision Framework ______________________________

The Santa Clara/Mojave River District Ranger is the Responsible Official for this project. The

District Ranger will decide whether to approve the proposed action, approve a modification to the proposed action, or take no action on treating the vegetation related to this project at this time.

Public Involvement _______________________________

The project was listed in the Schedule of Proposed Actions (SOPA) on the Angeles National Forest internet webpage beginning on April 1, 2010 and every quarter since. Scoping and public notification were conducted to inform the public of the proposal and provide them an opportunity to raise any issues associated with this invasive plant treatment proposal. A scoping letter was mailed out to approximately 370 agencies, groups, and individuals on August 18, 2010, which included a summarized description of the proposed action. A legal notice informing the public of this project proposal (with a 30-day scoping period) was published August 18, 2010, in the LA Daily News. The detailed purpose and need and proposed action document, map, and scoping letter were included on the Forest websites under “Projects and Plans” starting August 18, 2010.

(http://www.fs.fed.us/r5/angeles/projects/). This internet site was referred to in both the legal notice and scoping letter.

Additional requests for input were sent to Native American tribes, groups and individuals. On

September 21, 2010, the Forest Supervisor sent letters to two potentially affected tribes. A letter was also sent to 121 individuals and groups on the Forest list for the Native American community potentially interested in vegetation management projects. Using the comments from the public and internal resource specialists concerns the interdisciplinary team recommended a list of issues to be addressed with the responsible officials’ agreement.

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project

Issues __________________________________________

The Forest Service received and reviewed comments from fourteen individuals/groups, both orally, by e-mail, and in writing, during the scoping period. The Forest also received suggestions from the

District and Forest staff. The Forest analyzed these comments to determine what the issues were related to this project proposal. Issues are points of discussion, dispute, or debate about the environmental effects of proposed actions. A list of comments and how they have been used are noted in appendix A in this document. Some comments were used to generate issues and some were used to direct the needed analysis. Many of the comments supported the proposed action with specific recommendations.

The interdisciplinary team recommended and the responsible officials approved three key issues that would be addressed in the analysis based on the internal and external scoping:

1. Herbicides can be toxic and have unknown effects to humans, including carcinogenicity, reproductive and developmental toxicity, neurotoxicity, and acute toxicity.

2. Herbicides can be toxic and have unknown effects to aquatic organisms, mammals, and birds.

3. Failure to successfully treat invasives on the National Forest will have adverse effects on

National Forest resources as well as downstream and adjacent landowners and water suppliers.

In addition, this document addresses the effects from this project for the following resources: invasive plants, special status plant and animal species (i.e., species protected under the Endangered Species

Act and Forest Service sensitive), hydrology, special land designation areas (i.e., wilderness), recreation, and scenic resources.

CHAPTER 2 - ALTERNATIVES, INCLUDING THE

PROPOSED ACTION

This Chapter describes the alternatives that were considered to determine if they would achieve the purpose and need discussed in Chapter 1 of this document. Alternative 1 is the no action; alternative 2 is the proposed action; and alternative 3 was developed in response to the issues identified during scoping and noted above (i.e., unknown herbicide toxicity). In addition, design features

(protection/mitigation measures) are incorporated into the alternative descriptions and are included in this chapter. The intent of these measures is to decrease potential adverse effects to people and the environment. This chapter also acknowledges alternatives considered but eliminated from detailed analysis. A table at the end of this chapter presents the alternatives in comparative form, displaying summary differences between the three alternatives and providing a basis for choice among options by the decision makers and the public.

Alternative 1, No Action

Under the no action alternative, only very minor treatment of invasives would occur. This would be primarily at project sites where separate project specific analysis and NEPA compliance had been a part of the project. The small amount of work that is being done currently is almost entirely manual treatment in the few areas where manual treatment alone can be successful. The no action alternative would not preclude doing NEPA compliance for invasive plant treatment activities in the project area at some time in the future. This alternative represents the existing condition and expected future conditions (in the absence of this project), against which the other alternatives are compared.

Alternative 2, Proposed Action The District Ranger of the Santa Clara/Mojave Ranger District is proposing the eradication, control, containment, and/or suppression of existing and new infestations of invasive plant species that are undesirable, noxious, harmful, injurious, or poisonous, including but not limited to State-listed high priority noxious weeds (such as yellow star thistle, arundo, tamarisk, and tree-of-heaven) in the Santa

Clara Watershed. The project area includes all National Forest System lands within this watershed, Treatment areas (Figure 1 and 2) would include non-National Forest System lands if the landowners/managers would like to enter into a cost-share agreement authorized under the Wyden

Amendment or some other available authority. The project would be a long-term commitment for invasive plant management in the project area due to new species entering into the project area, re-colonization of treated species, and expansion of existing populations. The term of this project would be 15 years with the intent to review and, if needed, update the project, effects analysis, and possibly purpose and need after 15 years of implementation. No new roads or trails are proposed as a part of this project. Off-highway motorized equipment will not generally be permitted for implementing this project. On a case by case basis, the District Ranger will determine if exceptions are needed in certain locations where resource damage can be avoided and it is important in implementation. The wildlife biologist, botanist and archeologist will review the proposal for the Ranger to make sure heritage resources and threatened and endangered species and critical habitat are protected.

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project

Figure 1. Project Area Map, West Side.

Figure 2. Project Area East Side

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project

Alternative 2, Proposed Action - Adaptive Management Strategy

Invasive plant infestations constantly change and evolve, as do the treatment methods. Early detection and rapid containment of invasive plants is the most efficient method for controlling their spread. The proposed action includes an adaptive management strategy that addresses these types of changes over the life of this project to allow for a rapid response for control and/or containment. New treatment methods (including change in concentrations or application methods of approved herbicides and/or biological control agents analyzed and approved for use by the US Department of Agriculture, (Agricultural Plant Health and Insect Services) and California Dept. of Food and Agriculture, treatment of new species, and/or treatment of new areas within the project area would be part of the proposed action as long as the scope of the treatment and the effects are within those addressed in this document.

This strategy would not allow for the use of new herbicides not addressed in this document; would not allow for “broadcast” (including aerial or boom sprayer) applications of herbicides; would not allow herbicide use during pre-emergence of vegetation (preventing the invasive plant from germinating); and would not allow large and heavy equipment into the treatment areas (e.g. large bull dozers). The use of any new herbicides, broadcast applications, pre-emergent herbicide application, or use of large and heavy equipment (large dozers) would require new National Environmental Policy

Act (NEPA) analyses, public involvement, documentation and decision. Appendix D, Section 3.1.2 provides a decision key that incorporates the adaptive management strategy approach.

Annual Implementation Review Process

As part of the adaptive management strategy, the Forest will have an annual Invasive Species

Management Implementation Review Meeting/Workshop. At this time, the proposed plan of work for the upcoming year will be reviewed, and any lessons learned from previous monitoring and implementation would be incorporated into the annual program of work. Other Districts and Province

Forests as well as partners in invasive species management will be invited to share lessons learned.

Any new information affecting planned implementation would be reviewed by an appropriate interdisciplinary team; documented; and annual treatment approved by the District Ranger and Forest

Resource Officer. The interdisciplinary team will include personnel as determined by the Resource

Officer and affected District Rangers, but will include as a minimum, an archeologist and biologist to insure protection of heritage resources and threatened and endangered species and their critical habitats. The documentation of the meeting would be included in the project record available for public review.

Alternative 2, Proposed Action – Priority Species There are a large variety of invasive species presently known to exist within the project area. This alternative divides invasive plant species into three categories: high, moderate, and low-priority species. Table 1 provides a summary of the high and moderate priority species that presently exist within the project area

Broadcast spraying is defined as spraying via ground vehicles or aircraft with hose sprayers or booms using an array of spray nozzles. This method is not selective and all species, both native and non-native are sprayed. Bare soil between plants is generally sprayed as well.

Table 1. List of high and moderate priority invasive plants.

Common name Taxon name

High Priority Invasive Plant Species

Arundo, Giant Reed Arundo donax

Saltcedar, Tamarisk Tamarix spp.

Tree of Heaven Ailanthus altissima

Spanish Broom Spartium junceum

Tree Tobacco Nicotiana glauca

Yellow Star Thistle Centaurea solstitalis

Moderate Priority Invasive Plant Species

Perennial Pepperweed Lepidium latifolium

Eupatory Ageratina adenophora

Brome Grasses Bromus spp.

Pampas Grass Cortaderia spp.

Scotch Broom Cytisus scoparius

Cape-ivy, German-ivy Delairea odorata

Fennel Foeniculum vulgare

French Broom Genista monspessulana

English Ivy, Algerian Ivy Hedera helix, H. canariensis

Italian Ryegrass Lolium multiflorum

Crimson Fountaingrass Pennisetum setaceum

Castorbean Ricinus communis

Himalayan Blackberry Rubus armeniacus (Rubus discolor)

White sweetclover Melilotus alba

Bigleaf Periwinkle Vinca major

Most treatment strategies would be intended to eradicate or control the high-priority invasive plant species. Dependent on location, invasive plant species, and potential vectors in the area, the strategy to manage the moderate and low-priority invasive plant species would consider containing and/or suppressing.

Alternative 2, Proposed Action – Invasive Species Treatment Prescriptions Prescriptions for treatment would follow integrated weed management (IWM) for each treatment site.

No single management technique or treatment method is perfect for all invasive plant treatment situations. Multiple management actions are required for effective treatment. Integrated weed management includes an approach for selecting methods for eradicating, containing, controlling, and/or suppressing invasive plants in coordination with other resource management activities to

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project achieve optimum management goals and objectives. This approach uses a combination of treatment methods, that when taken together, would eradicate, contain, control, or suppress a particular invasive plant species or infestation efficiently and effectively, with minimum adverse impacts to non-target organisms. This approach contrasts with the traditional approach of using a single treatment type, such as applying herbicides, to treat all invasive plant problems. Herbicides are one useful technique, but they are not the only method to control invasive plants and may not always be the most effective.

In addition, there are multiple herbicides that can treat a given invasive plant species. Integrated weed management is species-specific, tailored to exploit the weaknesses of a particular invasive plant species, site-specific, and designed to be practical with minimal risk to the organisms and their habitats (Colorado Natural Areas Program 2000).

Potential herbicide and manual/mechanical treatment prescription options for many known and expected invasive plants are provided in Appendix C.

Alternative 2, Proposed Action - Treatment Methods Proposed treatment methods include biological control (e.g. insects, pathogens), manual/mechanical, fire wilting, and herbicide. These treatment methods are divided up further into specific types of treatment methods and are summarized in table 2. The timing of herbicide treatments would be dependent on the invasive plant species, location of the population, temperature extremes, restrictions for species protection, as well as wind and rain restrictions (which vary by herbicide). The Regional

Forester must pre-approve any herbicide or biological control treatment in the Magic Mountain

Wilderness (Forest Service Handbook (FSH) 2109.14, 13.4; USFS 1994a; Forest Service Manual

(FSM) 2323.04c; USFS 2007b). This needed approval would occur before a decision in made on this project.

Depending on the size of the activity generated material (invasive plants), treatment of this material

(biomass) could include pile and burning adjacent to or at the treatment site (at a minimum, outside the 25-year floodplain), drag and remove off site (if vehicle access is adjacent to treatment area), or helicopter sling load material out of the treatment area for disposal off site (e.g. if the access is poor and pile and burning in place is not an option. If the biomass material is minimal, the material could be scattered above the high waterline to dry and decompose. Sites where tamarisk plants receive herbicide treatment would not be burned, and treated plants would not be cut for two growing seasons after initial treatment because disturbing the treated plants can induce some to resprout. Some material resulting from treatment may be sold or given away as special forest products (flower arrangements etc.) or used as biomass for approved purposes.

The selection of treatment method would be dependent on time of year; severity of infestation;

presence of sensitive resource areas (e.g. native plants and wildlife species, including protected species); degree of intermixing of invasive species with sensitive native habitats; access; proximity to surface water; and budget.

Table 2. Summary of treatment methods proposed.

Method Description

Biological Control Method

Biological Control Agents

Biological control agents are normally insects or pathogens that attack specific invasive plant species. Prior to allowing use, US Department of Agriculture, Agriculture Plan Health and Insect Service (APHIS) is required to complete NEPA analysis and documentation. There is only one potential biological control agend that has this required analysis completed, Eustenopus villosus.

It is the only species which will be used for this proejct.

Use of this method would comply with the APHIS NEPA document and decision. Biological control would only be used to target yellow starthistle.

Advantages and disadvantages –suppresses the spread of infestations but would not likely

Method Description eradicate the invasive plant populations. If successful, can provide permanent, widespread control with a favorable cost:benefit ratio.

Manual/Mechanical Methods

Hand Pulling

Pulling or uprooting plants can be effective against some shrubs, tree saplings, and herbaceous invasive plants. Annuals and tap-rooted plants are particularly susceptible to control by hand pulling. It is not as effective against many perennial invasive plants with deep underground stems and roots that are often left behind to resprout.

The advantages of pulling include its initial small ecological impact, minimal damage to neighboring plants, and little (or no) cost for equipment or supplies. Normally effective with small populations and/or where a large pool of volunteer labor is available. The key to effective hand pulling is to remove as much of the root as possible while minimizing soil disturbance. For many species, any root fragments left behind have the potential to re-sprout, and pulling is not effective on plants with deep and/or easily broken roots. Disadvantages are that this method is labor and time intensive. Often times there are low mortality rates, which require repeated re-treatments to be effective, which could increase the project cost and frequency of disturbance to the treatment area.

Manual/Mechanical Methods

Pulling Using Tools

Most plant-pulling tools are designed to grip the plant stem and provide the leverage necessary to pull its roots out. Tools vary in their size, weight, and the size of the invasive plant they can extract. The Root Talon is inexpensive and lightweight, but may not be durable or effective as the all-steel Weed Wrench, which is available in a variety of sizes.

Both work best on firm ground as opposed to soft, sandy, or muddy substrates and in small areas with easy access.

Advantages are initial small ecological impact and minimal damage to neighboring plants.

Normally effective with small populations and/or where a large pool of volunteer labor is available. Disadvantages include both tools can be cumbersome and difficult to carry to remote sites, this method can be labor and time intensive, often requires repeated re-treatments to be effective, which could increases the project cost and frequency of disturbance to the treatment area. Could spread invasive plants to other sites if equipment is not cleaned before leaving an infected site.

Clipping and Cutting

“Clipping and Cutting” requires cutting a portion of the invasive plant stem, generally cutting the bole of the tree/plant with cutting tools such as chainsaws, weed wacker/whip/eater.

Advantages and disadvantages are similar to the “pulling using tools” method as noted above. Another disadvantage is that many species can resprout from the base.

Girdling For trees (e.g. tamarisk), the main trunk of the trees would be stripped of the bark (consisting of secondary phloem tissue, cork cambium, and cork) around a tree’s outer circumference, causing its death. Death occurs from the inability of the leaves to transport sugars (primarily sucrose) to the roots.

Advantages to this treatment method are minimal ground disturbance and effective in killing larger sized trees. A disadvantage is that it takes time for the tree to die and during that time the tree can still produce seed. Another disadvantage is that some species can resprout from the base.

Tarping Invasive plants would be cut back within inches of the ground and opaque thick tarps or pond liners would be staked or weighed down over the treatment area. The tarp(s) would be applied in late spring/early summer and remain for up to 5 months, usually from June to November. This treatment is best used in small areas (less than 0.25 acres) where there is not an intermix of native plants.

Advantages to this treatment method are minimal ground disturbance and it has been known to be effective in small areas. Disadvantages are limited size of treatment area, could damage soil microorganisms, and high monitoring needs in high public use areas to ensure the tarp is left in place.

Fire-wilting Method

Flaming Weed Torch

The weed torch is a treatment method that utilizes a propane torch to kill individuals but not ignite them This treatment is known as flaming, wilting, or blanching and the equipment can

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project be carried by an indiviudal. The weed torch would only be used during times of low fire danger and in areas where there is low potential to carry fire. The most effective application is for the control of small diameter woody vegetation (one inch in diameter or less) such as French broom, other broom species and gorse, seedlings, and nonwoody grasses and forbs. To reduce potential for wildfire, ‘flaming’ is typically only undertaken when vegetation is very wet- either during or immediately after a rain event, or when vegetation is damp from fog and on low wind days (less than 5 mph is preferable).

An advantage to this form of treatment is that it has very minimal environmental impact. A disadvantage is the limited window of opportunity for treatment.

Herbicide Methods

Hand/Selective Treatment of individual plants to avoid spraying other desirable plants. There is a low likelihood of drift or delivery of herbicides away from treatment sites. This method is used in sensitive areas, such as near water, to avoid getting any herbicide on the soil or in the water. Specific methods include:

a) Foliar Application (including basal bark) – These methods apply herbicide directly to the leaves and stems/trunk of a plant. An adjuvant or surfactant is often needed to enable the herbicide to penetrate the plant cuticle, a thick, waxy layer present on leaves and stems of most plants. These applicators range from backpack sprayer, to hand-pumped spray or squirt bottles, which can target very small plants or parts of plants.

b) Spot spraying – Spot spraying is similar to foliar spraying but would be for larger sized plants and/or population of plants. The focus still is on treating individual plants (instead of broadcast spraying) but over a larger area. Applicators would typically be backpack sprayers. Because of the potential to treat larger areas and larger sized vegetation, this method has a slightly higher potential for drift.

c) Frill or Hack and Squirt – The frill method, also called the “hack and Squirt” treatment, is often used to treat woody species with large, thick trunks. The tree is cut using a sharp knife, saw, or ax, or drilled with a power drill or other device.

Herbicide is then immediately applied to the cut with a backpack sprayer, squirt bottle, syringe, or similar equipment.

d) Cut-Stump – This method is often used on woody species that normally resprout after being cut. Cut down the tree or shrub, and immediately spray or squirt herbicide on the exposed cambium (living inner bark) of the stump. The herbicide must be applied to the entire inner bark (cambium) within minutes after the trunk is cut. The outer bark and heartwood do not need to be treated since these tissues are not alive, although they support and protect the tree’s living tissues. The cut stump treatment allows for a great deal of control over the site of herbicide application; therefore, has a low probability of affecting non-target species or contaminating the environment. It also requires only a small amount of herbicide to be effective.

e) Cut, Resprout, and Spray or Paint/Daub – Cut 1-2 months prior to spraying. Apply herbicide when resprouts are 2-4 feet tall, but most effective in early fall through winter when plant chlorophyll is transferred to roots. Herbicide should be applied on dry days and during low winds.

f) Stem Injection – Herbicides can be injected into stems using a needle, syringe, or special cutting tools, such as basal injectors or breast height injectors.

g) Basal Bark Treatment - Herbicide is applied to the base of individual woody plants or stems - individual plant treatment. The herbicide penetrates through the bark to the cambium, where it translocates to roots and stems for complete control. Used for trees less than 6 inches in diameter and trees that are too tall for foliar application.

h) Wicking application - applying a herbicide consists of a wick or rope soaked in herbicide from a reservoir attached to a handle. The wetted wick is used to wipe or brush herbicide over the weed.

Advantages include little soil disturbance, highly selective and effective with little risk of drift of herbicide onto non-target species. Disadvantages include labor intensive and weather conditions must be suitable for herbicide application (and for stem injections, equipment could be expensive). For immediate herbicide treatment after cutting, coordinating cutting and herbicide application in a timely fashion would be difficult. A disadvantage of herbicide treatment is the potential for toxicity effects from the chemicals used.

Depending on the invasive plant species, over time, the amount and concentration of herbicide needed would likely decrease and the amount of manual treatment could increase as the project enters into a monitoring and management phase with only small pockets or individual scattered plants needing treatment.

Herbicide Treatment Method The five herbicides that are considered as treatment options in the proposed action include:

aminopyralid, chlorsulfuron, glyphosate, imazapyr, and triclopyr. Table 3 provides a summary of the typical application rate and range planned for each herbicide. These five herbicides were chosen because of their effectiveness in controlling specific target plants while being some of the safest herbicides available for invasive plant treatment in natural areas.

Table 3. Summary of range of and typical application rates for each herbicide proposed.

Herbicide Range of application rate

(pounds of acid equivalent/acre [lb a.e./acre])

Typical application rate (lbs a.e./acre)

Aminopyralid 0.03 to 0.11 0.078

Chlorsulfuron 0.0059 to 0.83 0.056

Glyphosate 0.5 to 8 3

Imazapyr 0.03 to 4 0.45

Triclopyr 0.05 to 10 3

Herbicides generally need to be applied with an adjuvant. There are several types of adjuvants including surfactants, non-foaming agents, and colorants.

A surfactant, or surface-acting agent, is any compound added to an herbicide formulation or tank mix to facilitate and enhance the absorbing, emulsifying dispersing, spreading, sticking, wetting, or penetrating properties of herbicides. Surfactants are similar to detergents in their action, reducing water surface tension to allow wetting and penetration of the plant tissues. The surfactant helps to achieve optimum herbicide absorption onto the plant. Surfactants may also improve an herbicide’s efficiency so that the concentration or total amount of herbicide required to achieve a given effect is reduced. This can reduce overall implementation costs, sometimes as much as five or ten-fold (Tu et

al. 2001). In some cases, the herbicide would already have the surfactant included, but in other cases, it would be necessary to add one. This alternative designates a range of dilution rates for nonylphenol polyethoxylate (NPE) based surfactants of 0.25 to 2.5 percent and a typical dilution rate of one percent.

Defoamers are used to reduce the foaming that might occur during agitation of the spray mixture.

Colorants can be added to herbicide solutions to enable spray crews to see where they have sprayed after initial evaporation of the solution. This alternative would utilize Hi-Light Blue dye or similar biodegradable colorant to facilitate visual control of application. This colorant is a water soluble dye and contains no listed hazardous chemicals. It is considered virtually non-toxic to humans (Bakke

2007).

Herbicide treatment would comply with local, state and federal pesticide laws and regulations including Forest Service policies, and would be applied strictly in accordance with the label directions

(BMP 5-8). At a minimum, only certified personnel or those under the supervision of a certified applicator would be allowed to use restricted-use pesticides (FSM 2154.2; USFS 1994b). Table 4 summarizes the active ingredients, examples of brand names, properties, and general uses of the herbicides that are included as part of the proposed action. All herbicides considered under the

Preliminary Environmental Assessment Santa Clara Watershed Invasive Plant Treatment Project proposed action have human health and ecological risk assessments that are posted on the Forest

Service website (http://www.fs.fed.us/foresthealth/pesticide/risk.shtml).

Table 4. Herbicides considered for use, including examples of trade names, and how they affect plants.

Active Ingredient, examples of brand names, action Properties

General uses/known to be effective on:

Aminopyralid (e.g. Milestone

, Milestone VM

Mimics natural plant hormones.

Selective systemic herbicide. Use for annual, biennial, and perennial broadleaf species.

Chlorsulfuron (e.g. Telar

DF, Glean

Corsair ™

Inhibits amino acid synthesis.

Absorbed by the leaves and translocated throughout the plant.

Use for broadleaf species and grasses.

Glyphosate (e.g. Accord

, Roundup

Aquamaster , Rodeo

Inhibits 3 amino acids and protein synthesis.

A broad spectrum, non-selective, translocated herbicide.

Translocates to roots and rhizomes of perennials. While considering non-selective, sensitivities do vary depending on species.

Adheres to soil, which lessens or retards leaching or uptake by non-targets.

Most effective on perennial plants when applied in later summer and fall, when plants are entering dormancy (e.g. arundo).

Some products have been approved for aquatic environments and can be used when surface water is present(e.g. Aquamaster®, Rodeo®).

Imazapyr (e.g. Aresenal

, Chopper

Stalker , Habitat

Amino acid synthesis inhibitor.

Broad-spectrum, non-selective, pre- and post-emergent herbicide.*

Most effective as a post-emergent.

Low potential for leaching into ground water. Has low toxicity to invertebrates and is non-toxic to fish, mammals, and birds. It can damage non-target plants, by transfer between root networks.

Used for annual and perennial grasses, vines, brambles, and broadleaf species (e.g. tamarisk).

Habitat® been approved for aquatic environments and can be used when surface water is present.

Triclopyr (e.g. Garlon

, Access

, Renovate

Mimics the plant hormone auxin, causing uncontrolled plant growth.

Selective systemic herbicide. Use to control woody and herbaceous broadleaf plants (e.g.

tree-of-heaven). Has little or no impact on grasses.

Product(s) has been approved for aquatic environments and can be used when surface water is present.

* Though imazapyr in general, can be used as a pre-emergent herbicides, this treatment method would not be used for Alternative 2. As noted earlier, no herbicide would be used as a pre-emergent.

Biological Control Treatment Method Biological control (biocontrol) involves the reduction of pest populations through the use of natural enemies such as parasitoids, predators, pathogens, antagonists, or competitors to suppress pest populations. Biological control is a practical option for suppressing pest populations because it is target specific, it can be implemented as part of an Integrated Pest Management (IPM) program and once established, populations are self-sustaining. The goals of the using biological control agents are to prevent the establishment, slow the spread, and manage invasive species of significant environmental importance.

The following are steps are followed by Animal and Plant Health Inspection Service (APHIS) and

California Department of Food and Agriculture (CDFA) prior to biocontrol release: 1) Accurate identification of the pest species and confirmation of the pest as a target for biological control, 2)

Surveys for natural enemies (generally insects, mites, nematodes and diseases) are conducted in the area of origin of the pest (usually overseas), 3) Determine host-specificity of potential control organisms to assess impact on targets and nontargets and environmental safety, 4) Following approval from federal and state regulatory officials, biological control agents are shipped to a domestic quarantine facility where they are examined to confirm species identity and to determine whether they are free of parasites and diseases, 5) These agents are tested in field plots to determine that the agents do reduce densities of the target pest and do not have adverse effects on nontargets.

Once this small scale testing is completed, appropriate natural enemies can be mass-reared to high numbers and released at field sites established by county…