Factor 4. Habitat Alteration Expected as a result of the Project such as logging
prescriptions, road construction, fuels prescriptions, change in grazing
management or recreation use, intensity and extent of disturbance

LOW risk: Activities that maintain more than 60% canopy cover and remnant understory
vegetation

MODERATE risk: Activities that maintain 40% - 60% canopy cover and remnant understory vegetation

HIGH risk: Activities resulting in less than 40% canopy cover and remnant understory
vegetation

In general, invasive non-native plant species establish and recruit in areas of ground disturbance,
especially where forest canopy is diminished. Logging, temporary and permanent road construction, fuels
prescriptions, and the machinery used to perform these activities can create disturbed soils, reductions in
vegetative ground cover, and reductions in canopy. The conditions created are conducive to the
introduction and spread of noxious weeds.

Where complete removal of vegetation is expected (e.g. shrub/vegetation removal in fuel corridors,
landing development, and regeneration harvest), the risk of introduction and spread is considered to be
HIGH. Where partial removal of vegetation in forested habitats results in an average canopy closure of
40-60%, the risk of spread into the setting is MODERATE in the short-term until such time that the
canopy fills in the gaps and understory vegetation and where canopy cover is greater than 60%, the risk is
considered LOW.

Factor 5. Increased Vectors as a result of Project Implementation such as road
construction, facility construction, amount of project-related traffic

MODERATE risk: other areas of project

HIGH risk: increased traffic on 2850 and 2S48 including the use of machinery associated with
project implementation, and use of landings and turnouts along these roads.

Determination of Risk

Given yellow star-thistles ecology and roadside distribution within the project area, the evaluation of the 5
factors above result in a moderate to high risk of introducing and spreading yellow star-thistle within the
project area. Hence, the following project design features are designed to mitigation measures to reduce
or eliminate that risk prior to project approval.

Project Design Features to Reduce Risk

In keeping with Forest Service policy on Invasive Species Management (FSM 2900); the following
project design features are identified to reduce the risk of introduction and spread from its current risk
rating of high to a low risk. Design features will be included in contract specifications, burn plans, unit
cards and other documents associated with the details of implementation. Priority areas for treatment
along 2850 and 2848 will be flagged in the field prior to treatment. Yellow star-thistle locations are
captured in Appendix A of this document and the appendix of the Environmental Assessment and in
Geographic Information Systems shapefiles with attributes to be used for implementation maps and
contracts as needed.


Appendix A — Map of Yellow Star-thistle Locations

Jauuosied g4 pue W7¢ ‘VasN.

feowarztos3:
jsonorZ408391

roworzrosaor

8L0z ‘Z Aenuer
SUOHEIO] SPSIUJEIS MO|LOA

\\ 398fo1g aagesogejog yeesgieny epispeoy eF IS}

SS
[EEX



54CESO17JDM04 0.01 | 472,586 | 4,458,776 2848 0.51
54CESO17JDMOS 0.01 | 472,550 | 4,458,772 2848 0.48
54CESO17JDM06 0.01 | 472,666 | 4,458,954 2848 0.81
S54CESO17JDMO7 0.01 | 472,778 | 4,458,933 2848 0.88
54CESO17JDM08 0.01 | 472,777 | 4,459,022 2848 0.97

1.07 Near
54CESO17JDM09 0.03 | 472,860 | 4,459,071 2848 Landing
54CES017JDM10 0.01 | 473,122 | 4,459,207 2848 1.46
54CESO17JDM11 0.01 | 473,111 | 4,459,278 2848 1.51 At Landing
54CESO17JDM12 1.30 | 473,435 | 4,459,203 2848 1.76 to 2.00 | At Landing
54CESO17JDM13 0.05 | 473,427 | 4,459,398 2548 2.05
54CESO17JDM14 0.74 | 473,641 | 4,459,345 2848 2.13 to 2.27
54CESO12JDM01 0.02 | 473,726 | 4,459,365 2848 2.30 tO 2.34

Factor 2. Habitat vulnerability based on previous disturbance, plant cover, soil
cover, shade, soil type, aspect/moisture

LOW risk: Forested areas with high canopy cover

HIGH risk: | Oak woodlands, forested (harvested) areas with low canopy cover, early seral
communities, road edges, and burned areas

The project area possesses attributes that are conducive to yellow star-thistle introduction and spread.
These attributes include relatively open habitats including oak woodlands, areas of reduced canopy and
overall vegetative cover, areas of ground disturbance due to past logging, road construction, road
maintenance, and private land developments. There are also burned areas as a result of the Mad River
Complex of fires in 2008. Yellow star-thistle is intolerant of shade and readily invades open and disturbed
settings. A majority of the project area is forested, which is not considered to be a habitat type vulnerable
to noxious weeds that might occur in the area.

Factor 3. Non-project-dependent vectors such as existing roads and trails, traffic
use, livestock/wildlife migrations, wind patterns, drainage flow directions

HIGH risk: roads, wind patterns, livestock grazing and wildlife movement

Roads are a primary vector for the introduction and spread of weeds (Gelbard and Harrison 2003). Use of
roads associated with the project area, especially those adjacent to known occurrences of invasive species,
can lead to a high risk of spread of invasive non-native plant species. Yellow star-thistle is wind-
dispersed, and as such can disperse over long distances.

Areas where livestock concentrate such as water troughs are subject to sometimes intense ground
disturbance which creates a setting conducive for invasive plant establishment. Livestock can also serve
as vectors for transport of yellow star-thistle seed, via seeds embedded in mud attached to hoofs. The 1st
48 project lies within the Van Horn grazing allotment, and as such is subject to spread of noxious weeds
via livestock activities.


e All mechanical equipment used in the project, including equipment related to road maintenance,
shall be pressured washed prior to operating on the Forest (USDA/USFS 2014).

e All mechanical equipment used in the project shall be washed after operating if moving from an
infested to an un-infested area.

e Asa part of contract specifications, treatment of mechanical units shall follow a progression of
work schedule, whereby treatment occurs first where invasive plants are limited to non-existent
before moving to heavily infested areas (e.g. the lower infested stretch of 2848). If progression
of work is not feasible, equipment operating in infested road segments shall be cleaned before
relocating (USDA/USFS 2014). Progression of work applies to road maintenance associated with
this project as well (see Appendix B).

e Avoid yarding/skidding through yellow star-thistle infestations.

e Asa part of contract specifications, immediately before using existing landings occupied by
yellow star-thistle, mechanically remove the plants to the edge of the landing, away from where
equipment will be operating; pile and subsequently burn. Use native material to mulch landings
following their use.

e Avoid masticating sections of 2850 and 2848 occupied yellow star-thistle.

e Where yellow star-thistle infestations are present, surface blade 2848 in such a way that bladed
material in not reincorporated into the road travel way but rather is push completely off the travel
way to prevent it from re-establishment.

e Inthe Fall, following surface blading, manually pull or use tools to remove individual plants,
removing as much of the roots as possible.

e Pile treated plants and burn where treated or if plant numbers are few, incorporate plant material
into a nearby burn pile.

e Include treated areas in the prescribed burn footprint.

¢ If practicable, stock pile wood chips generated on site for application to treated yellow
star-thistle sites.

Monitoring Plan

Successful control of yellow star-thistle would necessitate periodic monitoring and evaluation of
treatment efficacy. If present after initial treatment manually pull or use tools to remove individual plants
in the late spring of the year (before fruiting/seeding) ensuring removal of the roots as much as possible.
Pile treated plants and burn where treated or if plant numbers are few, incorporate plant material into a
nearby burn pile. Monitor annually and retreat as necessary and until no plants persist.

Progression of Work

The following Units occur in the vicinity of yellow star-thistle infestations and as such should be treated
last in order to reduce the risk of introduction and spread; 308, 401, 402, 403, 404, 405, 406, 407, 408,
409, 410, 411, 418, 421.

This progression of work will be included in the contract for this project and in road engineering contracts
associated with project implementation. If this progression of work cannot be implemented, then


Invasive Non-Native Plant Risk Assessment
and Project Design Features
1st 48 Roadside Fuelbreak Collaborative Project
Mad River Ranger District, Six Rivers National Forest
January 15, 2018

NM Ne Ke p~ 1a 718

otanist


contractor shall clean equipment operating in any of the units associated with the section of road
identified above before operating elsewhere in the respective Focal Areas.

Literature Cited
DiTomaso, J. and E. Healy. 2007. Weeds of California and Other Western States. University of
California Agriculture and Natural Resources, Publication 3488. Pages 250 — 260.

Gelbard, J.L. and S. Harrison. 2003. Roadless habitats as refuges for native grasslands: interactions with
soil, aspect, and grazing. Ecological Applications 13 (2003), pp. 404-415.

USDA/USFS. 2011. Forest Service Manual. FSM 2900. Invasive Species Management.
https://www.invasivespeciesinfo.gov/toolkit/controlgeog.shtml

USDA/USES. Six Rivers. 2014. Best Management Practices: Invasive Plant & Aquatic Organisms.
Signed April 18, 2014, Tyrone Kelley, Forest Supervisor. On file Six Rivers National Forest.


1st 48 Roadside Fuelbreak Collaborative Project

Invasive Non-Native Plant Risk Assessment

Introduction

Key to keeping invasive non-native plants at bay on Six Rivers National Forest is management of existing
infestations and of the vectors that introduce and spread these plants on Forest with particular emphasis
on the management of satellite or leading edge occurrences. In regards to the latter we have a rare
opportunity to manage and possibly even eradicate occurrences before population numbers explode to a
point of no return. The main emphasis of the Invasive Non-Native Plant section of this document is an
evaluation of the risk of introduction and spread of invasive non-native plants from actions proposed
under the action alternative, Alternative 2. The risk evaluation leads to project design features that are
designed to mitigate project effects by reducing the risk of introduction and spread of invasive non-
native plants from the existing condition of high to the desired condition of low.

Policy

In accordance with the policy within Forest Service Manual 2900 Invasive species management
(USDA/USFS 2011), the Forest shall abide by the following as a component of project decision
document:

e Determine the risk of introducing, establishing, or spreading invasive species associated with any
proposed action, as an integral component of project planning and analysis, and where necessary
provide for alternatives or mitigation measures to reduce or eliminate that risk prior to project
approval.

e 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.

e Make every effort to prevent the accidental spread of invasive species carried by contaminated
vehicles, equipment, personnel, or materials (including plants, wood, plant/wood products, water,
soil, rock, sand, gravel, mulch, seeds, grain, hay, straw, or other materials).

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

Direct and Indirect Effects

Tf left unmanaged (no action alternative) invasive non-native plant species directly threaten ecosystems
by displacing native species. Indirectly, over time they can reduce species diversity, and degrade
wildlife and fisheries habitat. Yellow star-thistle has been shown to be toxic to horses, leading to injury
or death, and as such can indirectly degrade rangelands and lower private property values (DiTomaso, et.


al. 2007). In addition to degrading rangelands and lowering property values, widespread infestation of
yellow star-thistle can indirectly lead to soil erosion and siltation in streams.

An evaluation of the risk of introduction and spread from actions proposed under the action alternative,
Alternative 2, follows. The risk evaluation leads to project design features that are designed to
mitigated effects noted above by reducing the risk of introduction and spread from the existing
condition of high to the desired condition of low.

Cumulative Effects

The spatial extent of the cumulative effects analysis is the project area within which the greatest
concern exists for the introduction and spread of invasive non-native plants by actions occurring during
the implementation of the roadside fuelbreak. The temporal time span would be the implementation
time span of the project. Management of the direct and indirect effects via the project design features
that are designed to mitigated effects noted above by reducing the risk of introduction and spread
would remove the source of infestation and, hence, there would be no cumulative effects.

Methodology - Evaluation of Risk

Risk is evaluated in an assessment for this project based on five indicators: 1) presence of known
invasive plant species in the project area, 2) habitat vulnerability, 3) non-project-dependent vectors such
as existing roads or trails, adjacent private property, 4) habitat alteration expected as a result of project
implementation, and 5) increased vectors as a result of project implementation.

Roads are vulnerable settings for the introduction and spread of invasive non-native plant species.
Invasive plants are highly adapted to settings that are chronically disturbed and with little to no shade.
Seeds of these plants can be inadvertently introduced to new areas on vehicles or equipment (the latter
used in road maintenance), attached to domestic animals, or imported on rock/gravel/straw or other
material used on roads or for erosion control. Once introduced, seed banks produced by yellow star-
thistle can last a decade or more and germinate when subjected to scarification (alteration of the seed
coat) by mechanical or thermal means.

Factor 1. Presence of known non-native invasive plant species identified as a
Forest concern

HIGH risk: As a result of surveys conducted by Six Rivers National Forest botanists, yellow star-
thistle infestations were found to exist on edges of forest roads 02S50 and 02848. The
following table provides the location of these sites. Sites will be flagged in the field and
identified by the INFESTATION ID. Note that UTMs are centroids of infestations. Mile
posts were derived in ArcMap and are approximate.

Road .
INFESTATION ID | AREA_AC | NAD83X_| NAD83Y Number Mile Post Notes
5ACESO17TECO1 0.22| 471,943 | 4,459,472 2550 0.19
54CESO17JDM02 0.02 | 472,339 | 4,458,783 2548 0.33 to 0.36
54CESO17JDM03 0.01 | 472,377| 4,458,803 2848 0.37 At Landing