Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-1

Affected Environment and Environmental 

Consequences

3-11 Vegetation and Silviculture

3-11.1 Introduction

The following section provides the scope of analysis, methodology, and indicators as well as the current 

affected environment to assess the environmental consequences of the alternatives for vegetation. The 

direct, indirect and cumulative effects to the vegetation are summarized from the Vegetation and Silviculture 

specialist report (Rojas 2011) for the KREW Project. 

3-11.2 Scope of Analysis, Methodology, and Indicators

Computer models were used to describe the vegetation current condition, then to grow and display direct 

effects (post treatment), indirect (future) effects, and cumulative effects (landscape and future) for each 

alternative. The Bull Unit contains 9 stands identified by Plan ID, and the Providence Unit contains 21. Each 

management unit was also partitioned into areas that were delineated as either in or out of the experimental 

watershed (Figure 2-2 and Figure 2-3, respectively).

Scope of the Analysis

The overall methodology for evaluating effects on vegetation is based upon assessing changes to vegetation 

growth, vegetation structure, ecological restoration, fire severity, and the need for herbicide use. 

Changes in vegetation and fire severity are compared against current vegetation structure, post treatment 

vegetation structure, and vegetation changes resulting from growth and mortality. Changes in vegetation 

growth and mortality, and measures of ecological restoration (proportion of large trees) are assessed post 

treatment and over a 30 year time frame. 

Conifer regeneration, survival and control of competing vegetation are compared against The LRMP 

objectives for minimum stocking and regeneration standards (Forest Plan 4-18) through site preparation prior 

to planting. The HSRD has followed the recommendation in the literature to control competing brush before 

reaching densities of 10,000 cubic feet per acre or 20 percent canopy cover (. The 10,000 cubic feet/acre can 

be visualized as brush one foot high covering approximately one fourth of the area in a stand. Competing 

vegetation is compared against this standard, past experience and effectiveness of treatments. 

Cumulative effects on vegetation are analyzed at the local scale of neighboring or adjacent projects (4900 

acres), and at a large landscape scale (72,000) acres (Rojas 2011). Vegetative cumulative effects are additive. 

That is they are the total of changes or proposed changes to vegetative structure. Analysis of neighboring 

projects allows for comparison and changes to vegetation that occur and could contribute to cumulative 

changes in vegetation at a small scale. The landscape scale analysis allows for comparison of changes that are 

occurring as a result of the past, present, and reasonable foreseeable projects across several large 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-2

watersheds within the conifer zone. Changes in the coniferous forest have the greatest potential for 

cumulative effects on fire severity, vegetation structure and ecological restoration.

Methodology and Modeling Used in the Analysis

Baseline forest inventory data were collected on Forest Inventory Analysis plots and Common Stand Exam 

plots taken throughout the project areas. Geographic information systems were used to assign plot data to 

vegetation polygons in each stand to create simulation units. The Forest Vegetation Simulator (FVS) was used 

to grow trees (Crookston 1997). 

Alternative 2 (2004 Framework -uneven-aged) simulation units were assigned old forest, general forest 

thinning strategies, or no thinning. Alternative 3 (The 2001 Framework) simulation units were assigned 

either defense, old forest, general forest thinning strategies, or no thinning. Model treatments were 

assigned canopy cover and tree size removal limits consistent with the alternative descriptions.

For the Alternative 4(GTR-220), restoration model runs divided the project area into three aspect topographic 

zones: canyon/fisher, neutral, and southwest. A tree removal prescription based upon a landscape strategy 

presented in An Ecosystem Strategy for Sierran Mixed Conifer Forests by North et al. (2009), aspect, site 

productivity and topographic zones, and using residual basal areas for each thinning strategy were modeled 

to reflect the treatment activities. 

Simulation units for each action alternative were overlaid with treatment areas determined from field 

review. Edges of the project area between modeled and proposed treatment areas were edge matched. This 

overlay allowed modeled results to accurately reflect the treatment areas described for each alternative. The 

No Action Alternative vegetation growth and fire behavior reflects an alternative with no treatments. 

While computer models attempt to display the complex reality of vegetation; modeling results fall short of a 

precise (perfect) depiction of the variability of real forest vegetation (Shifley 1998). This short coming is due 

to the variability associated with measuring vegetation, the variability in locating plots, the errors associated 

with drawing boundaries around vegetation, the ability of algorithms used in the computer models to assign 

plot data to polygons and the effective reduction of natural variability by algorithms. 

Indicators

These factors were used to assess the consequences of the No Action, Proposed Action and other treatment 

alternatives.

Change in Forest Structure

Proportion of landscape over 50 percent tree canopy cover.

Proportion of a project exceeding the stand density threshold.

Numbers of trees per acre removed and retained

Brush cover

Changes in stand attributes resulting from a potential wildfire or from proposed prescribed fire

Conifers, black oak and brush 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-3

The influence of treatments, brush and grass on tree survival and growth

The influence of treatments on brush and grass 

The need for herbicides

No. of Large Trees and Species Composition 

Proportion of pine species

Proportion of large trees

Change in number of snags

Resistance to Change -resilience

Resistance to wildfire and prescribed fire vary with both vegetation composition and structure. 

Loss of stem area (basal area) and scorch height are indicators of fire resistance

Restoration 

Restoration reflects the synergy between tree density, tree growth, fire severity, large trees, species 

composition and resilience. Landscape heterogeneity is also used as an indicator of ecological restoration 

and reflects the variability in tree density and the arrangement of forest structure across many forest stands. 

(see page 17 section 3.2.3.4 for a more detailed explanation of restoration assessment indicators)

3-11.3 Affected Environment

Regulatory Setting

Management direction contained within the National Forest Management Act (1976) Sec. 4. (d)(1), states 

that “it is the policy of Congress that all forested lands in the National Forest System shall be maintained in 

appropriate forest cover with species of trees, degree of stocking, rate of growth and conditions of stands 

designed to secure the maximum benefits of multiple use sustained yield management in accordance with 

land management plans.” Furthermore, the Act requires that “All national forest lands treated from year to 

year shall be examined after the first and third growing seasons and certified ... as to stocking rate, growth 

rate... Any lands not certified as satisfactory shall be returned to the backlog and scheduled for prompt 

treatment.”

The Pacific Southwest Region (R-5) of the Forest Service has developed specific stocking standards for 

successful reforestation (USDA 1992). These require a specified minimum and recommended number of 

seedlings per acre. These numbers vary from a minimum of 75 seedlings per acre for ponderosa pine type on 

poor sites to 200 trees per acre for a mixed conifer forest on good sites. These numbers reflect the number 

of seedlings needed to establish a growing forest. They also reflect the knowledge that not every seedling 

has the genetic potential to thrive on the micro-site they were planted in. It also requires that the seedlings 

be well-distributed and growing under conditions that will allow them to “persist into the future” (USDA, FS, 

R-5 FSH. 2409.26b, 1991).
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-4

Forest Plan management directions for plantations are to apply silvicultural and fuel reduction treatments to 

accelerate the development of old forest characteristics, increase stand heterogeneity, and reduce the risk of 

wildfire loss (SNFPA, ROD, Appendix A-2).

In addition CFR 219.27 (c) directs that management prescriptions that involve vegetative manipulation of 

tree cover for any purpose shall be best suited to the multiple-use goals established for the area with 

potential environmental, biological, cultural resource, aesthetic, engineering, and economic impacts. Section 

(c) further directs that tree removal treatments be chosen after considering potential effects on residual 

trees and adjacent stands; Avoid permanent impairment of site productivity (site quality); be practical in 

terms of transportation and harvesting requirements, and total costs of preparation, logging, and 

administration. 

In order to have common measures of productivity, the Forest Survey Site Class utilizes a seven-class system 

where each class is defined in terms of a range of cubic foot volume yield at culmination of mean annual 

diameter growth. Site index values developed from Dunning and Rieneke’s Bulletin 354 (1937) were used to 

assign measures of productivity and compared to the Forest Survey Site Classes. This comparison is found in 

the project file. Bulletin 354 values are displayed for each stand in this section.

A field examination of each stand was conducted and data collected for each stand. Field examination and 

data were used to measure effects to adjacent stands and residual trees. Field reviews also eliminated areas 

not suitable for treatments or that did not meet the multiple-use purpose and need of the KREW Project. 

NFMA requires that a certified silviculturist determine if silvicultural practices are in compliance with the 

Forest Plan (36 CFR 219.27 (c) & (d)) In addition, NFMA requires that the harvesting system to be used is not 

selected primarily because it will give the greatest dollar return or the greatest unit output of timber. 

Harvest systems and silviculture treatments are designed to meet LRMP standard and guidelines to reduce 

fire behavior, increase fire fighter safety, protect wildlife habitat and meet LRMP desired forest structures.

Regulations (219.27 (c)) (7)) require that timber harvests and other silvicultural treatments shall be used to 

prevent potentially damaging population increases of forest pest organisms. Silvicultural treatments shall not 

be applied where such treatments would make stands susceptible to pest-caused damage levels inconsistent 

with management objectives. In addition, Region 5 Regional Forester directed (July 14, 2004) that when 

designing thinnings managers will ensure that density does not exceed an upper limit (for example: 90% of 

normal basal area, or 60% of maximum stand density index); this is a prudent way to avoid the health risks 

associated with density. Design thinnings to ensure that this level will not be reached again for at least 20 

years after thinning.

3-11.3.1 Existing Condition 

Vegetation within the KREW project area is the result of past disturbances. These disturbances include large 

pine harvests (1860 to 1984) , wildfire (1947), even-aged management (1970 to 1992), insect mortality, 

wind/snow damage (1984, 2005 and 2010), and salvage harvests. Harvests within the KREW Project area 

began in 1870s with removal of sugar pine and ponderosa pine typically in small groups or single trees near 

Glen Meadow Creek (Sudworth 1900a, Flintham 1904, Hurt 1940). However, most harvests were limited 

until 1937. From 1937 to 1984 portions of stands 208, 235, 250, 292, 236, 301, 316, 299, 331, 316, 380, and 

449 in the Providence Unit were privately owned and logged by the Pine Logging Company (later American 

Forest Products). These properties were later transferred to the Forest Service. Harvests from 1937 to 1989 

resulted in the removal of large diameter ponderosa/Jeffrey pine and sugar pine leaving understory incense 

cedar and white fir.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-5

Forest Service even-aged harvests in the project area largely occurred after 1970. Forest Service harvests in 

1970, 1972,, and 1979 occurred in the Bull Unit in stands 962, 965, 1056, and 1057 and created even-aged 

plantations and shelterwoods. Shelterwoods harvests leave large trees remaining after harvest to provide for 

suitable conditions for seedling establishment. In the Providence Unit even-aged harvest occurred in stand 

380 and 306. Even-aged treatments resulted in the creation of 524 acres of plantations, shelterwoods and 

overstory removal. Salvage harvest and hazard tree removal have removed dead and damaged trees

The Bretz Mill fire burned at high severity within stands 295 and 1043. This resulted in large openings. 

Subsequent pine planting resulted in dense stands of ponderosa pine in stand 295. A lack of natural 

regeneration or tree planting in stand 1043 has resulted in dense white leaf manzanita dominating stand 

structure. 

Wind and snow damage in 1984, 2005 and 2010 resulted in significant tree breakage and mortality. The 1984

wind event resulted in the toppling of large trees across the Bull Unit. This wind throw was salvage logged in 

the Patty Salvage sale. The 2005 and 2010 wind events occurred in the Providence Unit and broke tree tops 

between 5,000 and 6,000 feet.

Early twentieth century tree data collection (cruise data) (USDA 1926) indicate that pre-harvest stands were 

dominated by approximately 60 percent pine species. However, current stand structures are dominated by 

white fir and incense-cedar. Similar encroachment of white fir has been documented in the Teakettle 

experimental forest (North et al. 2004). Stand species composition was shifted from pine dominated mixed 

conifer to a fir dominated mixed conifer.

Plantations are dominated by young trees (< 25 years old) and a mixture of montane brush (whitethorn, 

green leaf manzanita, Sierra Gooseberry, Sierra Currant, and bear clover). Plantations contain 350 to 800 

trees per acre.

Existing Conifer and Black oak Vegetation 

Vegetation within the KREW Project is described using the California Habitat Relationship model (CWHR). 

This model describes vegetation by vegetation type, quadratic mean diameter, and canopy density (Mayer 

and Laudenslayer 1988). Existing acres of vegetation were determined by using aerial photographs, Landsat 

maps, field review and modeling. Existing structure was determined from approximately 400 plots collected 

from 2004 to 2008. Table 3.11-1 below indicates the percentage of each stand CWHR size and density class. 

Current existing vegetation is dominated by medium to large size tree cover (size class 4 and 5) and moderate 

to dense canopy cover (canopy density M and D) in the providence unit. The Bull Unit is approximately 

evenly split between moderate to dense cover of medium to large trees and open and sparse tree cover of 

small to large trees.

The Bull Unit is composed of sierra mixed conifer and red fir vegetation types. The Providence Unit is 

composed of sierra mixed conifer, montane hardwood, and ponderosa pine vegetation types. Rock (Barren) 

areas with less than 10 percent tree cover and Meadows are found across the Bull and Providence Units. 

Ponderosa pine vegetation type is found in the Providence Unit.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-6

Table 3-11-1 Site quality, percentage of CWHR size and density classes by stand, and vegetation type by stand

Vegetation Type

CWHR tree size and canopy 

class

Project

PLAN_ID

Acres

Site Index

Rock (Barren)

Montane hardwood conifer

Ponderosa pine

Red Fir

Sierra Mixed conifer

Meadow

Grand Total

3P,3S,5P,4P,4S,5S,2D,2M,2P,2S

3M, 3D

5M,5D,4M,4D

Grand Total

Providence

208 35 90 36% 0% 0% 0% 64% 0% 100% 69% 0% 31% 100%

235 97 90 1% 0% 0% 0% 95% 4% 100% 38% 0% 62% 100%

236 58 80 0% 0% 0% 0% 67% 33% 100% 34% 0% 66% 100%

250 28 80 0% 0% 0% 0% 100% 0% 100% 0% 0%

100

% 100%

280 75 70 11% 0% 0% 0% 89% 0% 100% 27% 0% 73% 100%

281 71 70 28% 0% 0% 0% 72% 0% 100% 33% 0% 67% 100%

292 30 70 0% 0% 0% 0% 46% 54% 100% 70% 0% 30% 100%

295 124 60 16% 0% 16% 0% 69% 0% 100% 31% 5% 64% 100%

299 157 70 2% 9% 0% 0% 87% 2% 100% 7% 0% 93% 100%

301 65 60 9% 0% 0% 0% 91% 0% 100% 25% 0% 75% 100%

306 137 40 5% 0% 0% 0% 95% 0% 100% 45% 1% 54% 100%

316 158 50 2% 0% 0% 0% 98% 0% 100% 4% 1% 95% 100%

331 123 60 12% 0% 0% 0% 88% 0% 100% 57% 0% 43% 100%

346 48 60 7% 0% 0% 0% 93% 0% 100% 16% 0% 84% 100%

365 84 60 0% 0% 0% 0% 100% 0% 100% 17% 2% 81% 100%

380 163 80 0% 0% 0% 0% 100% 0% 100% 27% 3% 70% 100%
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-7

449 166 70 14% 0% 10% 0% 75% 0% 100% 29% 0% 71% 100%

450 84 80 4% 0% 0% 0% 93% 3% 100% 58% 0% 42% 100%

499 72 70 0% 0% 100% 0% 0% 0% 100% 0% 0%

100

% 100%

1043 88 70 0% 0% 100% 0% 0% 0% 100% 2% 0% 98% 100%

Subtotal 20 1863 7% 1% 11% 0% 80% 2% 100% 28% 1% 72% 100% Project PLAN_ID Acres Site Index Rock (Barren) Montane hardwood conifer Ponderosa pine Red Fir Sierra Mixed conifer Meadow Grand Total 3P,3S,5P,4P,4S,5S,2D,2M,2P,2S 3M, 3D 5M,5D,4M,4D Grand Total Bull

796 111 50 7% 0% 0% 44% 45% 4% 100% 45% 0% 55% 100%

811 135 70 6% 0% 0% 0% 91% 4% 100% 52% 0% 48% 100%

838 153 70 8% 0% 0% 33% 49% 10% 100% 56% 0% 44% 100%

961 98 60 25% 0% 0% 14% 59% 2% 100% 46% 0% 54% 100%

962 101 80 0% 0% 0% 7% 91% 2% 100% 43% 0% 57% 100%

964 115 60 9% 0% 0% 0% 91% 0% 100% 41% 0% 59% 100%

965 93 70 10% 0% 0% 75% 15% 0% 100% 71% 0% 29% 100%

1056 93 60 15% 0% 0% 79% 0% 5% 100% 86% 0% 14% 100%

1057 295 50 9% 0% 0% 67% 22% 1% 100% 64% 0% 36% 100%

Subtotal 9 1194 9% 0% 0% 39% 49% 3% 100% 57% 0% 43% 100%

total 29 3057 8% 0% 6% 15% 68% 3% 100% 39% 1% 60% 100%
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-8

Vegetation within the KREW Project is a mosaic strongly affect by past disturbances (timber harvests, 

prescribed fire, fuels treatments, wind/snow damage), site quality and secondary succession. Stands are 

dominated by nearly 80 percent (basal area) white/red fir and incense cedar tree species that has encroached 

in understories (Figure 3-11-1) over the last one hundred years. The red fir tree species dominates stand 965 

and 1056 in the Bull Unit. Red fir, Jeffrey pine and lodgepole pine tree species are found mixed together in 

the Bull Unit. While Sugar pine, ponderosa pine and Jeffrey pine tree species are found in the providence 

project area. Both Unit areas contain lodgepole pine trees adjacent to meadows. Black oak is found 

scattered across the providence area, however it composes less than 10 percent of basal area. Stand 

1043 contains 16 percent black oak mixed with white leaf manzanita brush. 

Table 3-11-1 displays the distribution of vegetation types in each stand. The project area is dominated 

by mixed-conifer pine vegetation grouping.

Site index measurements indicate that stands have a moderate potential for tree growth and tree cover 

across the project (Table 3-11-1). However, rocky and thin soil (rock/barren vegetation type) is found 

across several stands. The area identified as rock and thin soil ranges from 36 percent to 0 percent of 

stand area. These rocky and thin soils are incapable of supporting dense tree cover and have site index 

values below 30. The site index values in table 3-11-1 represent average stand capabilities for tree 

growth. The values represent tree height of dominant trees at 50 years base age. Site index of 70 

indicates that dominant tree height will average 70 feet tall at age 50. Site index ranges from a low of 

40 in stand 306 to a high of 90 in stand 208 and 235.

Trees 10 to 30 inches diameter at breast height dominate stand structure with 51 percent of basal area 

for all stands (Figure 3-11-2) or about 190,00 trees. Figure 3-11-2 displays the distribution of tree basal 

area (stem area) by diameter class for each stand DBH. Trees greater than 30 inches, occupy more than 

40 percent of basal area per acre across the project area or about 31,000 trees.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-9

0%

20%

40%

60%

80%

100%

120%

Percentage of Diameter Class (%)

Stand Number

Basal Area by Diameter Class

0 to 10" 10" to 20" 20" to 30" 30" to 35" >35"

Figure 3.11-2 displays the proportion of tree basal area by species for each stand

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

Percent Basal Area

Stand number

Species Composition

White/Red Fir Incense Cedar Black Oak Sugar Pine Jeffrey/Ponderosa

Figure 3-11-1 displays the proportion of tree species composition for each stand
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-10

Brush cover 

Brush cover is found both in the understory and in openings. However, understory brush is less due to dense 

tree conditions. Brush cover ranges from more than 68 percent (stand 1043) to less than 1 percent in stand 

1056 (Figure 3-11-3). Sierra chinquapin (Castanopsis sempervirens) is found on thin soils and rock outcrops. 

Brush in openings and plantations is dominated by whitethorn (Ceanothus cordulatus), green leaf manzanita 

(Arctostophylos patula) in the Bull Unit area; Bearclover (Chamaebatia foliolosa), Deer brush (Ceanothus 

intergermis) and white leaf manzanita (Arctostophylos vicida). Bearclover (Chamaebatia foliolosa) is found in 

eight stands (281,295, 301, 306, 331, 449,499, and 1043). Deer brush (Ceanothus intergermis) is found in 

three stands (281, 285 and 499). Brush cover is highest in canopy openings or on rocky thin soils (Figure 3-11-

4)

Figure 3-11-3 Percent brush cover for each stand by brush species

0

10

20

30

40

50

60

70

80

235236280281295299301306316331346365380449499796811838961962964965

104310561057

Percent cover

Average Stand Brush Cover

Greenleaf Manzanita Whiteleaf manzanita Whitethorn Deer Brush

Buck Brush Bear Clover Sierra Chinquapin Sierra Gooseberry
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-11

Figure 3-11-4 Percent brush cover found in open canopy areas for each stand

Plantations and shelterwoods

Plantations and shelterwoods occupy 538 acres in portions of sixteen stands. These plantations range in age 

from 60 to 13 years. Table 3-11-2 displays the acres by year of planting or origination for each stand.

The 1947 Bretz fire caused high severity fire in fourteen acres in the western edge of the Providence Unit. 

These fourteen acres were planted with ponderosa pine in 1950. This plantation contains 13” dbh ponderosa 

pine 250 trees per acre.

Planted Jeffrey pine, sugar pine, and red fir range in height from 4 to 20 feet tall. In addition natural white fir 

and incense cedar are also found in the plantations. Density ranges from approximately 150 to 800 trees per 

acre. Brush cover within plantations and shelterwoods varies from none to more than 70 percent. 

Shelterwood areas in stand 450 have little or no brush in planted areas No treatments are proposed in this 

stand. Remaining plantations and shelterwood areas are dominated by dense mixture of ceanothus, 

manzanita, bear clover and oaks and conifers. 

Ninety-four acres of shelterwoods were created in 1984 in the Bull Unit. These areas have an overstory of 

scattered large trees (30” to 48” DBH) and dense understories of ceanothus, green leaf manzanita, and red 

fir, white fir, and Jeffrey pine. 

Stand 1043 contains 21 acres burned in the 1947 Bretz fire that is dominated by dense white leaf manzanita 

and bear clover.

Bear clover, ceanothus, and green leaf manzanita dominate plantation created after 1985. Two plantations 

in stands 250 and 236 are the result of previous private land owner harvests. Plantation trees in stand 250 

are heavily encumbered by cherry (prunus) and whitethorn (ceanothus).

There are no plantations found in stands 208, 236, 280, 281, 301, 316, 331, 346, 449, 796, 961, or 964.

0

10

20

30

40

50

60

70

80

90

100

Percent of Brush Cover (%)

Stand Number

Percent brush cover Openings
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-12

Table 3-11-2 Acres of plantation within in each stand by year of planting

Year of Planting

Project PLAN_ID 1950 1972 1985 1984 1989 1994 1995 1997

Brush 

Field

Grand 

Total

Bull

838 0 0 0 1 0 0 0 0 0 1

962 0 0 0 69 0 0 0 0 0 69

965 0 25 0 0 0 0 0 0 0 25

1056 0 15 0 0 0 0 0 0 0 15

1057 0 0 0 24 0 0 16 0 0 40

sub total 0 39 0 94 0 0 16 0 0 149

Providence

235 0 0 0 0 14 0 0 0 0 14

250 0 0 0 0 26 0 0 0 0 26

292 0 0 9 0 0 0 0 0 0 9

295 14 0 0 0 0 0 0 0 0 14

299 0 0 2 0 0 0 0 0 0 2

306 0 0 0 0 0 79 0 0 0 79

365 0 0 0 0 0 24 0 0 0 24

380 0 0 0 0 0 94 0 0 0 94

450 0 0 0 0 0 60 0 0 0 60

499 0 0 0 0 0 0 0 44 0 44

1043 0 0 0 0 0 0 0 1 21 22

sub total 14 0 11 0 40 257 0 45 21 388

Grand 

Total 14 39 11 94 40 257 16 45 21 537
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-13

Forest Structure-Stand Density and Canopy cover

Stand Density and Canopy cover

Stand Density Index (SDI) is a relative measure of tree density that compares existing tree density to a 

reference maximum density. SDI values beyond 35 percent of the reference maximum density indicate that 

site resources are at a “limiting density” for tree growth and vigor. SDI values beyond 60 percent of the 

reference maximum site resources are at the “lower limit” at which tree mortality from insect attack or intertree competition for water, soil, light, nutrients is imminent. 

Thirty-six percent of the project area is dominated by SDI above the lower limit of self thinning (60 percent of 

maximum). Forty-eight percent of the project area is between 35 percent to 60 percent of maximum SDI or 

at moderate risk to density or insect mortality. Providence Unit stands 346, 380, 499, and 1043 and Bull Unit 

stands 796 and 962 are dominated by areas at high risk to insect or density mortality. Seen another way 

these stands have more than 50 percent of acres subject to density or insect mortality. Four stands (208, 

250, 301 and 965) have less than 10 percent of acres subject to density induced and insect mortality. These 

four stands have rock or existing plantations that do not currently support or cannot support dense conifer 

vegetation.

Insect, disease and density induced mortality is disproportionately effecting pine species. Pine species 

currently make up approximately 20 percent of existing basal area, while more than 50 percent of standing 

dead trees (snags) are pine. Observations within the project area indicate that bark beetles continue to kill 

pine. 

Fisher Tree Clumps 

The identifiers for fisher rest sites as key habitat structures. Key fisher rest site structures are based upon 

descriptions in the literature that described rest site conditions and models (Zielinski et al. 2004a, Purcell and 

Thomson conversation). Tree canopy cover is a key indicator for fisher rest sites. Fisher rest site canopy 

cover is discussed as a component of the vegetation structure. 

Plot data indicates that high quality fisher rest site characteristics (excluding proximity to water) are found 

rarely or on approximately 1 percent of the project area. 

3-11.3.2 Restoration Strategies and Desired Conditions

Restoration of forest structure and function consistent with frequent low intensity fire are needs identified 

for the KREW Project. Alternative 2, Alternative 4 and Alternative 5 are designed to respond to restoration 

desired conditions. Approaches to restoration vary for each of these alternatives.

Alternative 2 promotes regeneration through reforestation in groups and promoting uneven-aged forest 

structures across stands consistent with historic reference conditions. Alternative 2 approaches restoration 

through strategies that mimic historical forest structures. Alternative 2 promotes structural restoration. Key 

forest structure components of the historical forest structure are large trees dominated, uneven-aged 

structure, relative low tree numbers and pine dominance. Structural restoration treatments are designed to 

be consistent with the SNF LRMP as amended by the SNFMP 2004 ROD.

Alternative 4 responds to the restoration needs by applying concepts outlined in An Ecosystem Strategy for 

Sierran Mixed Conifer Forest by North et al. (2009). The Ecosystem Strategy (GTR-220) focuses on treatments 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-14

that promote ecological processes while maintaining key Pacific fisher habitat and forest structures. 

Treatments seek to promote forest processes and structures consistent with frequent low intensity fire.

Ecological restoration treatments can be divided into those that:

retain key large tree structures needed by Pacific fisher,

reduce hazardous fuels, and

promote and maintain heterogeneity, 

increase proportion of large trees, 

and increase proportion of pine species

Alternative 5 incorporates structural restoration treatments within research watersheds and ecological 

restoration treatments outside research watersheds.

Structural restoration seeks to return forest structure, tree density, stem area (basal area) and species 

composition consistent with 1850 sierra forests. Historical Sierra Nevada forests developed prior to 

suppression of frequent fire across the landscape. These historical forests were dominated by large trees. 

Trees of many ages were found in groups typically less than 3 acres.

In contrast, ecological restoration (GTR-220) treatments do not seek to impose past historical structures, 

rather restoration treatments create stand and landscape conditions that are resilient in the face of both 

changing climate and dynamic forest functions (North et al. 2009). While treatments are similar to structural 

restoration, treatments are designed to achieve landscape heterogeneity in tree density. Desired conditions 

for the project area are consistent with structures developed under frequent low intensity fire of past Sierra 

Nevada forests. Alternatives are compared on the proportion of large trees, creating landscape 

heterogeneity, proportion of pine, and reducing the effects of wildfire severity.

Elements of mimicking past forest structures are found in both the ecological restoration strategy and the 

structural restoration strategy. GTR-220 recognized that “Historical forests can provide a better 

understanding of the ecological processes that have shaped mixed-conifer forest and the habitat conditions 

to which wildlife have adapted”. Thus existing data on tree density is compared to data reflective of past 

forest structures. 

Landscape and stand level desired conditions are consistent with the SNF LRMP. Desired conditions and 

treatments vary to create landscape and stand heterogeneity or create forest conditions similar to those that 

existed in the 1850s.

Ecological Restoration Strategy

There are different types of science literature that describe how Sierra Nevada forests developed under a 

frequent fire regime (Sudworth 1900, Show and Kotok 1924, Drumm 1996, North et al. 2004). Drumm 

(1996) indicates that mean fire return intervals prior to fire suppression near the KREW area were 

approximately 3 to 5 years. In the adjacent Teakettle Experimental forest fire return intervals were 12 to 17 

years.

These differences in fire severity created a forest structure and composition that varied by fire pattern that 

were controlled by slope aspect, slope steepness, topographic position and fire frequency (Stephens et al.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-15

2007, Fites-Kaufman 1997, Urban et al. 2000, Beaty and Taylor 2001, Taylor and Skinner 2004). Cumulatively 

these studies suggest forest landscapes varied depending on what structural conditions would be produced 

by topography’s influence on fire frequency and intensity (North et al. 2009). Figure 3-11-5 displays 

graphically how these influences would be reflected on a landscape. 

Alternative 4 implements treatments depicted in Table 3-11-3 that vary based on 3 aspect and topographic 

zones that are related to soil moisture, solar radiation (temperature), and vegetation condition (Underwood 

et al. in progress): South/west facing slopes, canyons/fisher, and neutral. Approximately1700 acres of the 

projects 3500 acres are proposed for ecological restoration treatments. Ecological restoration treatment 

zones are composed of approximately the following proportions: South/west facing slopes =28 percent, 

canyons/fisher= 10 percent, neutral=18 percent, no mechanical=44. Neutral aspects receive sun in early 

morning or late evening.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-16

Figure 3-11-5 Graphical representation of landscape heterogeneity resulting in ecological restoration (North 

et al. 2009)
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-17

Desired Landscape structure-Heterogeneity

Landscape heterogeneity and restoration is accomplished in Alternative 2 through providing variable residual 

tree density for each topographic and aspect zone. Table 3-11-3 below describes the range of residual tree 

basal area (stem area), tree canopy cover percent and trees per acre for each aspect and topographic zone. 

Table 3-11-3 below is further divided by vegetation type. Mixed conifer fir have less than 15 percent pine 

species, pine areas have more than 40 percent pine, and mixed conifer pine areas have between 15 percent 

and 40 percent pine species. This tree occupancy (basal area) or canopy cover post treatment described in 

table 3-11-3 for restoration in Alternative 2 is proposed to move the project forest structure to the desired 

condition. Action alternatives retain canopy cover within stands consistent with the Forest plan – either 

greater than 40 percent or 50 percent tree canopy cover. Table 3-11-3 below identifies canopy cover for 

patches of land within stands. While individual patches of land may drop below the 40 percent or 50 

percent, the stand as a whole will meet the LRMP. In order to achieve the LRMP treatments are further 

constrained by limiting removals to 1/3 of existing basal area or 20 percent of tree canopy cover in certain 

land allocations (see Chapter 2 of this report). As a result of these constraints the desired conditions may 

not be met with this project proposal.

Table 3-11-3. The range of residual basal area, tree canopy, and trees per acres by aspect and topographic 

zones for all stands. 

vegetation type desired tree structure

Pine

Mixed 

conifer Pine

Mixed conifer 

fir

desired 

Basal 

Area 

per acre 

square 

feet

desired 

Trees > 

11” Per 

Acre

desired 

percent 

canopy 

cover

Aspect/topographic zone

Southwest 120 25 38

Southwest 150 28 43

neutral 160 33 44

canyon/fisher 

rest sites neutral Southwest 180 37 47

canyon/fisher 

rest sites neutral 210 40 52

canyon/fisher 

rest sites 240 46 56

Vegetation types are grouped into three broad forest types for modeling restoration: pine, mixed conifer fir, 

and mixed-conifer pine. These broad vegetation groupings, along with aspect and topographic zones, and site 

quality are used to assign residual stem area for ecological restoration. The pine vegetation type has greater 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-18

than 40 percent pine species (Jeffrey pine, and sugar pine); mixed-conifer fir areas have less than 15 percent 

pine species; and mixed-conifer pine has more than 15 and less than 40 percent pine species.

Measures of Landscape Heterogeneity

The canopy density of patches across the landscape is used to measure heterogeneity. The coefficient of 

variation (CV) is the ratio of the standard deviation of the mean values for canopy cover. This analysis uses 

the CV of canopy cover to measure heterogeneity across the project area and through time. 

Tree growth effects canopy cover by increasing tree density over time (Harris 1984). As patches across the 

landscape grow towards greater canopy density, the patches become more alike. Treatments can create 

different patch densities. The ecological restoration objective for landscape heterogeneity is met by creating 

low intensity disturbance that create patches of various tree density. The more land with different types of 

aspect and topographic zones, the more differences (heterogeneous) will occur after treatment. Conversely 

the more alike treatments or aspect/topographic zones are the less different (heterogeneous) the patches. 

Patch size affects heterogeneity (Gosz et al. 1999). Scale is affected by the intensity of disturbance and the 

scale of the data used to measure the disturbance. Vegetation growth results in patches becoming more 

similar (Haufler et al. 1999). As patches become more similar adjacent patches combine into larger patches. 

Thus fewer and fewer patches make up the project area or landscape (Gosz et al. 1999). Both treatment and 

mortality can affect how quickly or slowly these patches coalesce.

Currently 64 percent of the KREW Project area (1959 acres) is over 50 percent tree canopy cover. Seventyfive percent of the Providence project area and 48 percent of the Bull Unit are over 50 percent canopy cover. 

At the stand scale ecological restoration maintains forest structures important for wildlife and forest 

resilience consistent with frequent fire regimes (North et al. 2009). Pacific fisher rest structures, California 

spotted owl nest trees, decadent large trees, regeneration, and brush openings create within stand 

heterogeneity. The scientific literature and data also, indicate highly variable stand characteristics (trees per 

acre, basal area, and tree distribution).

Structural Restoration Strategy

Structural restoration seeks to return forest structures consistent with pre-1850 forests or prior to fire 

suppression: Large trees, pine dominance, and fewer trees. Figure 3-11-6 displays tree numbers for historical 

forest reference conditions. Figure 3-11-6 also compares the desired trees per acre with historical tree 

numbers. These historical reference trees per acre are assumed to have developed under frequent fire 

regimes. A comparison of desired conditions proposed for the relative lowest tree density management 

(general forest or Southwest zones) and relatively the highest tree density areas (old forest emphasis or 

canyon/fisher zones) indicates that restoration treatments proposed to leave somewhat more trees than the 

highest and lowest historical data sets. The desired condition would maintain approximately 40 trees per acre 

greater than 11 inches across treated areas. This average management range is higher than most of the data 

represented by forest structures developed under frequent fire. The higher tree numbers in the 

management range reflect objectives and LRMP desired conditions that balance forest resilience and

maintaining habitat for Pacific fisher and California spotted owl.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-19

Several data sets and studies provide reference conditions of forest structures under historical frequent fire 

regimes : existing unmanaged stands at the Teakettle Experimental Forest (Near Dinkey ), historical data 

from the turn 19th century and the 1930s (Bouldin 1999, Hasel 1931, Minnich et al. 1995, Sudworth 1900a, 

Sudworth 1900b Stephens and Fiske 1998), reconstructed stands (North et al. 2006, Taylor 2004, Covington 

et al. 1997), analogous relic mixed conifer forests at the Sierra San Pedro Martir in Baja California (Stephens 

and Gill 2004, Minnich et al. 2000). Each type of data and data set has limitations and short comings 

(Swetnam et al. 1999, Stephenson 1999). This data is represented and compared in Figure 3-11-6. Data in 

Figure 3-11-6 reflect open stand conditions with few trees typical of forest with frequent fire.

Figure 3-11-6 displays reference conditions for tree numbers greater than 11” and the desired 

conditions for tree numbers. The graph compares areas proposed to have relatively high tree 

density and those areas of relative low tree density under restoration strategies. The graph shows 

that the desired condition is higher than most of the historical data sets. This graph illustrates 

that while trees per acre are proposed to be reduced, trees per acre proposed for restoration are 

higher than historical conditions.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-20

 

Stand and landscape information indicates that the restoration strategy developed by North et al. (2009) and 

in the Proposed Action and Alternative 2 are suitable for implementation in the KREW Project area. Frequent 

fire had previously occurred in the KREW Project area similar to other Sierra Nevada forests (Phillips 1998, 

North et al. 2004). Desired conditions and proposed restoration treatments are consistent with forest 

structures developed under frequent fire regimes: low tree density, higher proportion of pine and oak 

species, higher proportion of large trees, reintroduces fire as a process, and promotes a heterogeneous 

forest structure. 

Figure 3-11-7 compares existing average stand conditions and desired restoration conditions for trees large 

than eleven inches in diameter. The graph shows that existing conditions exceed the average desired 

condition for tree numbers. 

3-11.3.3 Forest Resilience – Fire, climate, Insects, Species Composition

Resistance to change, a return to pre-disturbance character, and the ability to provide societies needs appear 

often in the literature for definitions of forest health (Eslkew 1995). A general definition of a healthy forest is 

one that has the ability to rebound from disturbance and maintain important forest structures after the 

disturbance (Kolb et al. 1995). For this project resilience is the ability of a forest to undergo disturbance and 

change and return to the same structure, function, vegetation type and ecological processes as prior to the 

disturbance. 

The action alternatives are not designed to eliminate insect mortality or crown fire from restoration treated 

forests, but rather to increase resistance to these events. Recent non-peer reviewed articles suggest high0

20

40

60

80

100

120

140

208235236250280281292295299301306316331346365380449450499796811838961962964965

104310561057

KREW

Desired Conditions vs Existing Conditions

Trees per Acre > 11" Desired Canyons Desired Southwest

Figure 3-11-7 compares the desired conditions across the project area for south and west (relatively 

lowest tree density) and canyons (relatively highest tree density) to the existing tree >11” by Stand.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-21

intensity, or stand-transforming, fire creates ecologically-vital “snag forest habitat”, which is rich with large 

snags, large downed logs, dense pockets of natural conifer regeneration, patches of native shrub habitat, or 

“montane chaparral”, and large live trees (Hanson 2010). This same literature indicates that high – intensity 

(high severity fire) is lacking and rather than a threat to Sierra Nevada Forests is a benefit. However, 

published peer reviewed articles indicate that there is no evidence that high-severity burned areas are 

deficient in the entire Sierra Nevada or the southern Sierra Nevada region. In addition, recent science articles 

indicate that research used by Hanson (2010) to support the case for more high severity fire are erroneous 

and deficient and do not support the conclusions for more high severity fire (Spies et al. 2009). Furthermore, 

articles used in Hanson (2010) show a bias against active management by ignoring recent science and risk 

factors in dry forests that do not support his opinions. 

Current science indicates that the total area of high severity burned forest in the Sierra Nevada is not lower 

than historic reference conditions (Safford 2010) and the size of high severity burned patches has significantly 

increased (Miller and Safford 2008, and Miller et al. 2009). Biodiversity of plants, fungi, and wildlife is not 

greatest in high-severity burned patches, but is maximized in diverse landscapes that incorporate a matrix of 

burn severities, forest seral stages (including managed forests), and most importantly, habitat diversity 

(Graber 1996, Wayman and North 2007, Meyer et al. 2008). Other research clearly indicates that high 

severity fire threatens Pacific fisher and California spotted owl habitat (Verner et al. 1992, Spencer et al.

2008). Without mechanical and prescribed fire treatments Pacific fisher habitat will become increasingly 

reduced and threaten populations (Spencer et al. 2008). Increasing the resistance to change from wildfire 

and bark beetle attack moves closer to addressing project needs and maintains important structures for 

Pacific fisher and California spotted owls following these disturbances (North et al. 2009). 

Insect mortality

Western pine beetle (WPB) is the primary cause of mortality of ponderosa pine and Jeffrey pine (Oliver, W 

1995, Oliver and Uzoh1997). In white fir and red fir, mortality is typically linked to a combination of fir 

engraver, density induced stress and disease (mistletoe and root disease) (Swetnam and Lynch 1993, Oliver, 

W 1995, Oliver and Uzoh 1997). While these insects and pathogens are native to the project, insect attack 

and mortality has increased (relative to the historical forest) due to the higher forest densities and reduced 

tree vigor resulting from many decades of fire suppression (Kilgore 1973, Savage 1994, Ferrell 1996, North et 

al. 2005). In some fire-suppressed forests, mortality from bark beetles has shifted to large-scale, episodic 

occurrences (Fettig et al. 2007). More trees in dense forests are susceptible to insect and pathogen attack 

because there is increased competition for resources, particularly during extended drought.

Increasing the resistance to bark beetle attack and increased tree vigor is a need of this project. Stand 

structure conditions that lead to attacks by western pine beetle and other insects that kill conifers are not 

completely understood. However, studies indicate that stand density is one important factor in insect 

mortality and tree vigor (Miller and Keene 1960, Oliver 1995, Smith et al. 2005). Other factors important for 

insect caused mortality and tree vigor are prolonged drought or injury and the presence of other diseases 

(Larsson et al. 1983, Ferrel 1996) and pollution (Grulke and others 2009). Tree density plays an important 

role in creating conditions suitable for insect attack (Miller and Keene 1960, Ferrel 1996). However, some 

studies indicate that well established trees in the Southern Sierra Nevada use water held in rock fissures or 

water deep in the soil (Hubbert et al. 2001). An inference that can be made from this research is that large 

trees are more resistant to drought and its effects.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-22

The range in stand density for the transition from limiting stand growth to imminent mortality has been 

identified on the basis of SDI (Sherlock 2007). SDI is a relative measure of tree density based on the SelfThinning Rule, also known as the –2/3 rule (Drew and Fleweling 1979) and first described in the Sierra 

Nevada (Rieneke 1933). “Very simply, it proposes that all environments with finite resources whether that be 

a goldfish pond or an acre of ground can support a finite amount of living biomass. Therefore, as individuals 

grow in size the number of individuals decline - an intuitive relationship (Oliver and Uzoh 1997).” Maximum 

densities have been determined for Sierra tree species based on plot data (Dixon 1994, Oliver 1995, Sherlock 

2007). The transition from endemic insect mortality occurs well before the maximum SDI is reached (Oliver, 

W 1995, Oliver and Uzoh 1997). 

SDI allows for comparisons of tree density between different species and different site quality. SDI compares 

density to a reference maximum density. While SDI has been shown to have an ecological basis for site 

occupancy by tree species, recent information for intermountain and cascade conifers indicates that it may 

underestimate the site occupancy by large trees and overestimate the occupancy by small trees in unevenaged stands (Woodall, et al. 2003). Never the less SDI has been shown empirically to have implications for 

tree competition for site resources (Rieneke 1933, Drew and Fleweling 1979, McCarter and Long 1986, Dean 

and Baldwin 1996). In addition others (Oliver 1995, Sherlock 2007) have described threshold levels for insect 

attack and tree vigor in the Sierra Nevada. 

As SDI increases beyond 35 percent of maximum (limiting density) insect mortality is possible (Oliver 1995, 

Oliver and Uzoh 1997, Sherlock 2007)). When stand density increases beyond approximately 60 percent of 

maximum (lower limit of self thinning or zone of imminent bark beetle mortality) insect or density mortality 

is imminent. These zones for the onset of tree stress do not predict when a tree or clump of trees will be 

attacked. This uncertainty of when a tree or clump will be attacked is due in part to the unpredictable nature 

of drought, site conditions, and the random dispersal of insects. SDI is used to display effects of alternatives 

on reducing the potential for insect mortality and reducing tree stress. Maximum SDI levels used for key tree 

species are:

white fir =759, 

sugar pine= 647, 

incense cedar =706, 

red fir= 800, 

Ponderosa pine =571 (without bark beetles), ponderosa pine =365 (with bark beetles Oliver 1995).

SDI 365 referred to in Oliver’s 1995 paper is effectively the maximum SDI, since bark beetles constrain the 

density of pines. As a result, it is common in the silvicultural profession to refer to 365 as the maximum SDI 

for ponderosa pine in California, rather than the “limiting density.”(Oliver 2010). 

Proposed treatments seek to increase resistance to density and insect mortality through tree removal 

(thinning). Black (2005) reviewed the literature on the effects of logging to control insects. Black’s review 

indicates that tree removal can increase tree vigor but is not effective in controlling infestations once a bark 

beetle outbreak occurs. Eighteen cited papers in Black (2005) report the effects of thinning on bark beetles, 

14 of these clearly show a positive effect of thinning on preventing bark beetle attack and mortality of the 

residual trees. The Black report cites 42 papers under “Effectiveness of Thinning” but only 18 of these papers 

report the effects of actual “thinning” on bark beetles. The other 24 cited papers report the effects of stand 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-23

density, salvage logging, tree physiology, fire, or other stand conditions but not thinning on bark beetle 

populations and dynamics. The benefits of reducing tree density and increasing resistance to insect attack is 

supported by studies that look at the stand structures that lead to insect attack in California (Oliver 1995, 

Oliver and Uzoh 1997) and studies that look at tree vigor (Miller and Keene 1960, Furniss and Carolin 1977, 

Larsson et al. 1983).

Guarin and Taylor (2005) found that in unthinned mixed conifer stands, similar to those found in the project 

area, mortality due to drought and insects ranged from approximately 39 percent to 59 percent. This study 

also found that ponderosa pine and white fir where most often killed. Guarin and Taylor (2005) also found 

that the tree density (trees ha_1) of standing dead trees, which is an index of recent tree mortality, was also 

much higher in the Sierra Nevada study site than in forests with an active fire regime (similar to restoration 

objectives for the project). On average, the Sierra Nevada forests studied have greater than 100-fold more 

dead trees (mean = 730 trees ha_1) than Baja California forests (3–23 trees ha_1) with the average plot in 

Baja California containing approximately 2 snags per acre. In contrast there are approximately 6 snags per 

acre in the KREW Project. In another study, Macomber and Woodcock 1994 found that within one drought 

and insect episode (1988-1991) in Northern Sierra Nevada white fir forest that 15 percent of standing volume 

was killed. Approximately 10 drought cycles have occurred over the last 100 years in the Southern Sierra 

Nevada. Each drought event would have the possibility of contributing towards mortality.

Another study by Grulke and others (2009) describes the progress of mortality during severe drought cycles. 

After the chronic drought in the San Bernardino Mountains (2002), bark beetles attacked, and there were 

clusters of tree mortality. However, the average stand tree mortality rate was near 0 percent. After the 

chronic and severe drought, tree mortality (primarily ponderosa pine) from both bark beetle and drought 

increased to approximately 5 percent at the stand level. In the spring following the wet winter, bark beetle 

populations reached epidemic proportions, and 42 percent of the stand had died. A similar progression of 

mortality is possible in areas above the threshold for imminent mortality. 

While past mortality episodes in forest similar to KREW Project area provide a range of mortality for thinned 

and unthinned forests (see above), a study by Mantgem and Stephens 2007 indicates that the tree mortality 

rate has increased over the past two decades in forests of the Sierra Nevada at a rate of approximately 3 

percent per year. This study indicates that tree mortality within the project area is increasing as a result of 

climate change.

The episodic nature and intensity of tree mortality described by studies for other California forests are 

indicative of the types of mortality that can or have occurred in the project area. These studies also indicate 

that tree density, insects, pollution and drought (similar to trees grown in areas above the threshold for 

imminent mortality) create a synergy that leads to the decline of tree vigor and a predisposition to fire 

severity (Grulke and others 2009). Recent studies indicate that the potential for phytotoxic ozone (O3) 

effects to sensitive pines and other species are expected within the KREW Project areas since various ozone 

exposure indices are among the highest of the studied forested mountain locations in Europe and North 

America and are similar to those found in the San Bernardino mountains (Cisneros and others 2010).
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-24

Fire Mortality

A need of the project is to alter fire behavior, to enhance the capability of fire suppression forces and reduce 

the loss of stand structure from wildfire. Alternatives are compared using model predictions using 97th

percentile weather conditions (Forest Vegetation Simulator and Fire Effects models) for loss of stem area 

(basal area) and scorch height from severe wildfire and prescribed fire. Scorch height and basal area loss 

have been used by others to predict fire severity (Omi and Martinson 2002). In addition, model predictions 

are compared to wildfires (Rock Creek fire, 1981; Big Creek fire, 1994), and results from prescribed fire on the 

HSRD are used to compare changes to stand structure. The Forest Vegetation Simulator model results are 

compared to observed fire effects. 

The indirect effects of treatments on fire mortality lessen with time. The effects of treatments lessen with 

time as a result of growth and mortality (Graham et al. 2004). The more distant in time a treatment occurs 

the less benefit results from that treatment. Simulations results are compared after harvest and fuel 

treatments. This date coincides with the completion of most of the activities in the alternatives, and thus 

reflects the effectiveness of treatments without the reduction ineffectiveness associated with time.

Several types of research describe effects of stand structure on fire behavior and fire severity: computer 

modeling results, post wildfire reviews, prescribed fire results, and anecdotal information (Pollet and Omi 

2002, Graham et al. 2004, Odion et al. 2004, Knapp et al. 2004, Knapp 2006, Knapp and Keeley 2006). This 

research indicates that reducing crown fire and subsequent fire severity can be accomplished by altering 

surface, ladder and crown fuels (Graham et al. 2004, Agee and Skinner 2005). The results of post wildfire 

measurements across the western United States indicate that fuels treatments can reduce fire severity. 

However, severity reductions are dependent on treatments, stand structure, and fire behavior and do not 

always result in reductions of fire severity (Pollet and Omi 2002, Odion et al. 2004). Fuel loading, topography, 

and weather are key in determining subsequent fire intensity and severity. Research dealing with the effect 

of a lopping and scattering of logging residue in combination with individual tree selection similar to the 

action alternatives indicated that more mortality occurs than thinning from below and lopping and scattering 

fuels similar to the 2001 framework alternative(Stephens and Moghaddas 2005). This is due to the number 

of small stems and the proximity of surface fuels and ladder fuels. Multistory stands have more ladder fuels 

and thus a greater opportunity for crown fire. However, a study by Perry et al. (2005) point to a difference in 

fire behavior and the potential for crown fire resulting from different methods used to model fire behavior. 

The method used by the forest vegetation simulator in this analysis may over estimate the potential for 

crown fire in the multi-aged stands created by the Alternative 2. Thus model results may overestimate the 

effect of small trees in the understory.

Climate Change

Climate influences the processes of growth and disturbance in which the historic forest developed (Keeley 

and Stephenson 2000). While climate cannot be influenced by landscape level manipulation, it can and has 

changed over the last 4,000 years. The climate affecting fire return intervals and plant growth for the 500 

years prior to 1900 was dominated by the little ice age (Millar and Woolfenden 1999). Fire return intervals 

and the resulting forest structure were the result of a wet and warm period prior to 1550 (medieval warm 

period) followed by a dry and cold period (little ice age) from 1550 to 1900. Changes in climate lead to shifts 

in vegetation zones and fire return intervals (Swetnam 1993, Urban and Miller 1999, Brunell and Anderson 

2002). The species composition changed while the presence of plant species remained constant (Millar and 

Woolfenden 1999). This past climate may not represent future climate changes. Current temperatures are 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-25

rising within a short-term cycle (100 years) while temperatures are declining on a longer cycle (1,000 years) 

(Millar and Woolfenden 1999). It is unclear what the future will mean for climate change. Maintaining the 

current mosaic of forest structures may not insure ecosystem stability (Millar and Woolfenden 1999, 

Schoennagel and Veblen 2004). Maintaining functioning processes and a wide range of age and class 

structures may be the most realistic approach in the face of uncertainty or changing climate.

Tree ring studies have established that compared to the previous two centuries weather during the 20th

Century was relatively moist without the decades-long droughts that occurred earlier (Ferrell, 1996). 

Beginning in the 1970’s temperatures began to warm noticeably. This warming resulted in a greater fraction 

of the Sierra Nevada precipitation falling as rain rather than snow, earlier snowmelt and earlier stream flow 

peaks (Dettinger, 2004). The combination of reduced stand vigor and excessive stocking combined with 

increasing temperatures and decreasing soil moisture availability is greatly increasing the threat of loss due 

to mortality from insect attack, diseases, competition, or fire.

The wetter than normal 20th Century coupled with the exclusion of fire has set the stage for stands to 

become overcrowded with competing conifers, oaks and other vegetation. Wide swings in climatic 

conditions over the past thirty years have placed stress on many of these stands. Local precipitation 

measurements indicate increasing precipitation with greater variability (Huntington precipitation station). 

Inter- tree competition, drought, rising temperatures, and insect attacks are beginning to take a toll on both 

plantation and wild stand trees. White pine blister rust has also been killing a number of sugar pine over the 

past ten to fifteen years. Dead and down fuel loadings have been on the rise. These conditions are not 

unique to the KREW Project area. More extreme examples can be found in the Lake Tahoe Basin, San 

Bernardino National Forest and in Arizona and New Mexico where entire stands of trees are dying. In 

southern California the amount of ponderosa pine mortality associated with western pine beetle, D. 

brevicomis Le Conte, infestations reached unprecedented levels after years of extended drought (Fettig, 

2007).

Substantial changes in extreme temperature episodes (fewer frosts, more heat waves) are anticipated 

(Dettinger, 2004). Over the past 17 to 29 years non-catastrophic mortality rates were found to have doubled 

over a series of 76 western forest plots. Increasing mortality rates could result in substantial changes in 

forest structure, composition, and function. This doubling of background mortality could cause a greater 

than 50 percent reduction in average tree age in a forest, and a potential reduction in average tree size (van 

Mantgem, 2009). Current projections of warming climates provide a greater opportunity for fire ignitions 

due to longer fire seasons. A higher probability of fire starts coupled with the changes in forest fuel 

conditions that occurred over the past century lead many to predict that large, generally more intense fires 

will become more likely than occurred historically (Skinner and Stephens, 2004). 

Species composition 

Ponderosa pine, Jeffrey pine, sugar pine and California black oak are found at lower frequencies than the 

historical Sierra Nevada forest subject to a frequent low intensity fire regime (Bouldin 1999, Taylor 2004, 

North et al. 2005). White fir occurs at higher frequencies. Ponderosa pine and black oak grow best in full 

sunlight; this characteristic is called shade intolerance. As stand densities have increased (more shade) 

ponderosa pine, Jeffrey pine and black oak have been reduced in abundance with increases in fir species. 

Pine species are more resistant to fire due to thicker bark, more open crowns and faster self-pruning. 

Providing for stand structures that encourage the growth of pines and oaks will increase the resilience of 

stand structures. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-26

The stem proportion of pine (basal area in square feet) is used to compare alternatives. In addition, the 

conditions for the growth of intolerant species are assessed. 

Action alternatives focused on restoration include treatments to maintain or increase the dominance of pine 

and oak species. These include favoring the removal of fir and incense-cedar, providing for greater growth of 

retained pine, and planting pine. 

The Alternative 3 (fuels reduction) focuses narrowly on reducing fire severity. While treatments will retain 

pine species over fir when possible, treatments do not seek to create growing conditions more favorable for 

pine and oaks outside of plantations and shelterwoods.

3-11.4 Environmental Consequences

Direct effects on vegetation are caused by tree removal, slash piling, mastication, prescribed fire, brush 

cutting, and chemical application. The direct effects occur at the same time and place as the proposed 

treatments. 

Indirect effects are caused by treatments and are later in time, but are still reasonably foreseeable. Indirect 

effects result from growth induced effects related to tree and brush growth rate, tree vigor, and fire 

behavior. Tree removal and subsequent growth have indirect effects on insect mortality and achieving 

restoration objectives. Prescribed fire Indirect effects result from reductions on wildfire behavior or insect 

attack that occurs after prescribed fire treatment activities. 

Cumulative impact is the impact on vegetation, which results from the incremental impact of tree removal, 

brush cutting, slash piling, mastication, prescribed fire and chemical application when added to other past, 

present, and reasonably foreseeable actions that effect vegetation structure, growth, or vigor. 

3-11.4.1 Assumptions

Treatments within the action alternatives include tree removal, fuels rearrangement, burning fuels, and

regeneration treatments. Each treatment is described in Appendix G

Tree removal occurs in trees 0 to 30 inches dbh in the Alternatives 2, Alternative 4 and Alternative 5 and 0 to 

20 inches in the fuels reduction alternative (Alternative 3). Trees greater than 10 inches dbh are removed as 

saw timber and generate funds. Trees less than 10 inches are burned, removed as biomass, rearranged for 

reduced flammability and reduced fire severity. Trees are removed consistent with thinning strategies in 

each alternative. Tables in Appendix G describe treatment acres for each alternative. Tree retention and 

removal are the result of marking guides. 

Following commercial tree removal, small trees not removed as biomass are felled. Following harvest 

removals, logging residue is rearranged through mastication, tractor piling, hand piling or lopping and 

scattering. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-27

3-11.4.2 Alternative 1—No Action

No direct change in conditions occurs as a result of this alternative. The potential for severe wildfire 

continues. Existing decisions to remove hazard trees will continue. The alternative identifies the baseline for 

action alternatives.

Direct and Indirect Effects

Direct Effects on canopy cover

Because the No Action Alternative implements no activities, there are no direct effects on canopy cover.

Indirect Effects 

Since the No Action does not implement specific activities to reduce tree canopy cover, unplanned events 

play the greatest role in controlling canopy cover. Indirect effects would occur as a result of growth, insect 

mortality, density induced mortality or unplanned fire events.

With no unplanned events, such as fire or insect attack, growth over the 30 year period would result in areas 

with greater than 50 percent canopy cover increasing from approximately 1,200 acres to 1,500 acres. Only 

the densest stands lose canopy cover as a result of mortality due to competition for water, nutrients and 

light.

Unfortunately, a large wildfire of 1,000 to 3,000 acres is a reasonably foreseeable event on a hot windy 

summer day. Approximately 1,000 acres with canopy cover of greater than 50 percent suffer severe damage 

under current conditions should a wildfire enter the project area (Table 3-11-4). The probability of a wildfire 

is assessed in the Fire and Fuels subchapter 3-2.

The year a wildfire occurs effects the amount of damage to tree canopy cover. A wildfire, occurring ten 

years in the future, results in an approximately 850 acre loss of areas with tree canopy cover over 50 percent. 

This improvement over time is due to increased tree size and the subsequent resistance to fire from larger 

trees. Untreated stands struck by a wildfire under the No Action Alternative would contribute little to 

maintaining canopy cover in fisher rest site habitat, spotted owl PACs, or goshawk PACs. These areas would 

be severely damaged. 

Direct Effects insect resilience

Because the No Action Alternative implements no activities there are no direct effects on stand density and 

insect risk.

Indirect Effects insect resilience

The No Action Alternative allows stands to increase in stand density. This increase is due to both the increase 

in size of existing trees and the growth of new trees filling in canopy gaps. New trees would be mostly those 

trees that do well in shade such as incense cedar and white fir. Portions of stands that are resilient to insect 

attack or are below the lower benchmark (35 percent of maximum SDI) are approximately 16 percent of the 

treated project acres (Figure 3-11-14). Within the Bull Unit 21 percent and in the Providence Unit 12 percent 

are resilient to insect and density induced mortality. After ten years of growth less than 10 percent of the 

project area is below the lower benchmark and resilient to insect mortality. At the end of the thirty year 

analysis period more than 80 percent of the project area is at high risk to insect mortality and density induced 

mortality and less than 5 percent is resilient. As stands begin to exceed the benchmark densities for 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-28

imminent mortality (35 percent of SDI) individual stress and disease weakened trees will begin to die. Pine 

species will see continued mortality with fir species experiencing mortality as more acres move beyond the 

high risk threshold. 

While mortality will reduce tree density, unplanned insect mortality is unlikely to achieve the project 

objectives. 

Historical weather data indicates that the Sierra Nevada experiences periodic droughts (McKelvey 1996, 

North et al. 2005). In below normal precipitation years, lack of water will weaken tree resistance and allow 

bark beetles to begin causing mortality in pockets. The mortality will likely exceed the periodic growth rate 

of stands (Oliver 1995). Dead trees will eventually contribute to the fuel load and secondary succession will 

result in the early dominance of created openings by brush species.

Epidemic mortality from bark beetles observed in the area in the late 1980’s exceeds modeled density 

induced mortality within the analysis area. Since 1930 each decade has seen significant occurrences of bark 

beetle mortality within the HSRD. No clear risk model for western pine beetle in the Sierra Nevada exists. 

However it is certain that stand and weather conditions as described in the previous paragraph that result in 

stand replacing insect mortality will persist in the analysis area under the No Action Alternative.

Direct Effects on large trees

Because the No Action Alternative implement no activities there are no direct effects on large trees.

Indirect Effects large trees

Restoration of forest structures, especially the number of large trees, requires time to develop and a period 

free of stand replacing events. The No Action Alternative maintains trees in dense stands providing limited 

growing space for diameter and crown expansion. Stand density is highest under the No Action Alternative. 

The No Action Alternative retains a smaller proportion of stem area (basal area) in large trees compared to 

the other action alternatives in each growth period. Trees larger than 35 inches increase in stem area 

without wildfire from approximately 25 percent to 35 percent of total stem area in the Providence Unit and 

from approximately 40 to 59 percent of stem area in the Bull Unit. Across all areas proposed for mechanical 

treatment the No Action sees large trees increase from 30 percent to 45 percent (see Figure 3-11-15). Low 

intensity wildfire and insect attack could benefit the accumulation of large snags and reduce understory 

vegetation. However, stand conditions lend themselves to high intensity disturbance when the reasonably 

foreseeable event of a wildfire occurs as described in the previous section. Acres expected to burn with low 

severity could experience some benefits from fire, while acres that burn with high and moderate severity 

would experience loss of large trees and in turn result in more losses of large trees than the action 

alternatives.

The No Action Alternative in the absence of severe wildfire retains less stem area in large trees than action 

Alternatives. When severe wildfire enters the project area, large trees are lost and the No Action Alternative 

has far less stem area in trees greater than 35 inches than the action alternatives. Low intensity wildfire and 

insect attack could benefit the accumulation of large snags and reduce understory vegetation. However, 

stand conditions lend themselves to high intensity disturbance.

Direct Effects species composition

Because the No Action Alternative implements no activities there are no direct effects on tree species 

composition.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-29

Indirect Effects species composition

The current dominance of mixed conifer stands by white fir and incense-cedar continues under the No Action 

Alternative. Under the No Action Alternative relative dominance in shade tolerant white fir and incensecedar increase from 75 percent to 80 percent of stem area (basal area) over the thirty year analysis period. 

This increase results from increases in white fir and incense-cedar tree numbers (in growth) and expansion of 

existing white fir and incense-cedar (growth).

Indirect Effects regeneration, brush openings, and competing vegetation

Existing openings are not reforested under the No Action Alternative. Unplanned events such as wildfire and 

bark beetles create openings in the forest canopy. No planting of these openings or existing openings 

created from unplanned events would occur. Reforestation would rely on secondary succession to reforest 

following unplanned events. These openings would likely continue to be dominated by brush similar to 

untreated stands examined in research (McDonald and Fiddler 1995). McDonald and Fiddler (1995) found 

that Sierra Nevada forest areas dominated by brush species required treatment to return conifer dominance. 

In another study, McDonald and Fiddler (1997) found that areas that lacked treatment to reduce manzanita 

or ceanothus had changes in the dominance of brush species through time, but brush continued to dominate 

and increased in dominance over 31 years. 

Many studies have shown clearly that brush competition slows the growth of conifers (Tappeiner and 

Radosevich 1982, McDonald and Fiddler 1990, McDonald and Fiddler 1995, McDonald and Fiddler 1997, 

Tappeiner et. al. 1997, McDonald and Fiddler 2001, McDonald et al. 2004, Powers et al. 2005). Conifers that 

do become established in the No Action Alternative could be up to two times shorter and thinner where bear 

clover, ceanothus, and green leaf manzanita compete with conifers (Tappeiner and Radosevich 1982, 

McDonald and Fiddler 1997, McDonald and Fiddler 2001). 

Thus conifer establishment under the No Action would result in very sparse numbers of trees. Openings 

would be dominated by bear clover, manzanita, or ceanothus. In those openings that favor conifer 

establishment high tree density will occur (McDonald and Reynolds 1999). New conifer establishment would 

continue to be dominated by shade tolerant species, incense-cedar and white fir, as these species grow 

under the shade of brush and other trees. Growth of conifers that will occur in these small openings would 

be slow (McDonald and Reynolds 1999) and dependent on site factors. It is not that conifers will not become 

established under the No Action Alternative, but rather that conditions that promote the establishment of 

shade tolerant and less fire resistant incense cedar and fir will continue. The growth of shade intolerant fir 

and incense-cedar trees will be slow due to brush and high tree density. 

Existing plantations would see brush volume and cover increase over the analysis period. Planted seedlings 

and samplings would slow in height and diameter growth as brush competed with the conifers for soil 

moisture. Mortality of plantation trees would occur reducing the number of conifers. Brush dominated 

plantations would favor the growth of incense-cedar and fir capable of survival in low light (shade tolerant). 

This shady condition would increase the dominance of these shade tolerant species. Conifers would 

eventually dominate the existing plantation areas but growth would be slow and prone to high fire mortality 

(McDonald and Fiddler 1990, McDonald and Fiddler 1995, McDonald and Fiddler 1997, McDonald and Fiddler 

2001, McDonald et al. 2004, Powers et al. 2005).

Understory brush would be reduced in cover and height in the No Action Alternative. In the absence of 

disturbances such as insect attack or severe fire trees will continue to grow. As overstory tree canopy cover 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-30

increases over the analysis period brush growth will slow and brush cover will reduce. When full crown 

closure occurs brush species will be reduced to scattered individuals or small clumps of brush.

Indirect Effects from Prescribed Fire and Wildfire

Indirect effects occur as a result of the reasonably foreseeable event of a wildfire. Under the existing 

condition and the No Action Alternative, approximately 65 percent of acres are at risk of sustaining high and 

moderate fire severity tree damage. Acres in high mortality increase to over 90 percent in 30 years in the 

project area. This increase in fire severity occurs with time as tree density increases and white fir and 

incense-cedar fill up the understory. 

While model results provide one means to assess the potential loss in habitat from wildfire a comparison to 

actual fire mortality is useful. The Rock Creek Fire occurred on the HSRD one mile from the project area in 

1981 and burned approximately 1000 acres of mixed conifer vegetation types similar to those found in the 

project area. More than two thirds of these acres resulted in stand replacement. The Big Creek fire burned 

on the HSRD in 1994. The Big Creek fire resulted in half the stands classified as high mortality. The fire 

resulted in a mosaic pattern in which half the conifer stand received moderate or high mortality. 

Model results for the No Action Alternative indicate that the potential high mortality varies over a 30 year 

time frame from approximately 65 percent at the start of the analysis to as much as 90 percent at the end of 

the analysis. Model estimates are consistent with measured mortality from similar stands on the HSRD 

subjected to severe fire. In addition the structural changes observed from both modeled results and 

observed changes from local fires are consistent with published results from several untreated stands 

subjected to wildfire (Omi and Martinson 2002, Safford et al. 2009). 

The indirect effect of growth and severe wildfire is that project areas under the No Action Alternative have a 

potential for dramatic stand structure changes during the analysis period.

Direct Effects on Restoration

Because the No Action Alternative implements no activities there are no direct effects on ecological 

restoration of forest processes and structure consistent with frequent fire regime.

Indirect Effects Restoration

The No Action Alternative moves the project area further from forest conditions consistent with frequent fire 

regimes. This is true for both scenarios with severe wildfire and without. The project area mixed conifer 

stands continue to increase in stand density on all aspects. This increase in small trees and tree numbers is 

out of character with the forest structures developed under Sierra Nevada frequent fire regimes. Existing 

conditions are also out of character with historical pre-1850 conditions.

While large trees will persist in scenarios without wildfire or drought, these scenarios seem highly unlikely 

based on past weather and fire risk. The No Action Alternative accumulates and maintains large amounts of 

small trees that result in ladder fuels. The increasing stand densities above the imminent threshold for insect 

attack indicate that resistance to insect attack decreases during the analysis period. Lower resistance to 

insect attack will result in more tree mortality due to insects. This mortality will eventually find its way to the 

forest floor and result in more accumulation of fuels. Accumulations of fuels and small trees result in wildfire 

conditions that kill many large trees over hundreds of acres. Both the severe stand replacing fire and the loss 

of large trees across so many acres is out of character with the frequent fire regimes of Sierra Nevada forests 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-31

and historical pre-1850 conditions (Weatherspoon and Skinner 1995, North et al. 2009). While the Sierra 

Nevada forests structures were driven by repeated low severity fire, the No Action promotes structures that 

are driven by high severity events such as wildfire and stand replacing insect attack.

Sierra Nevada forests subject to frequent fire was dominated by shade intolerant pine species (North et al.

2004). The No Action makes conditions less favorable for the establishment of shade intolerant species. 

Conditions suitable for the establishment of species that can regenerate under shade persist and increase as 

stands across the landscape become denser. Mixed conifer vegetation types that were historically 

dominated by pine species continue to be dominated by incense-cedar and fir. 

Cumulative Effects 

Current landscape activities such as plantation maintenance, underburns, hazard tree removal, power lines 

and private land owner treatments each will tend to lower canopy cover and reduce tree density. Current 

plantation maintenance treatments will reduce brush cover and increase conifer growth and canopy cover. 

Since underburns tend to reduce the number of small trees, and maintain large trees that provide canopy 

cover canopy cover reductions should be negligible. Hazard tree abatement removes scattered trees, 

typically less than 1 tree for each half mile of road treated. The scattered nature of the hazard tree program 

will result in no additional cumulative reduction in canopy cover. Adjacent private landowners reduce 

canopy cover as a result of timber harvests. Approximately 1,800 acres will have a reduction in canopy cover. 

Removing thirty percent of stem area across all diameters would result in canopy reductions in stands from 

60 and 70 percent to above 50 percent. Power line treatments will continue to keep approximately 371 acres 

from attaining dense tree cover. 

Current landscape activities combined with steady tree growth and the continue encroachment of shade 

intolerant species produce the cumulative effect of dense stands in excess of 50 percent canopy cover. The 

canopy cover is maintained in the absence of severe wildfire. 

However, these same dense conditions that accumulates across the landscape result in less resistance to 

severe fire and insect attacks. Acres of imminent insect attack increase across the landscape. Drought 

conditions that lead to severe wildfire and insect attack will occur across the larger cumulative effects 

analysis area. Greater loss in canopy cover, less resistance to insect attack, lower proportion of large trees, 

and fewer acres that achieve restoration objectives result when drought and fire enter the larger cumulative 

effects analysis area. The acres of 50 percent canopy are reduced with the No Action Alternative across the 

landscape with severe wildfire. 

The cumulative effect of growth across project area and adjacent untreated stands is increased density. This 

is in spite of lowered tree density on private lands and plantations. The landscape will accumulate more acres 

susceptible to bark beetle attack. As the areas that exceed the level of catastrophic insect attack grow larger, 

these areas will begin to form large patches at risk to epidemic bark beetle attack. These large continuous 

acres of high susceptibility to bark beetle attack will make the effects of inevitable drought more

pronounced. This cumulative effect of high-density stands across large landscapes is to create low resilience 

and thus a landscape with poor forest health.

The continued persistence of stands dominated by understory incense-cedar and white fir provide fuels 

ladders. The underburning program will lower understory vegetation across approximately 17,300 acres 

within the larger cumulative effects boundary. Fuels ladders, increased density and increased surface fuels in 

the remaining stands increase the potential for torching and crown fire. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-32

Species composition continues to be dominated by incense-cedar and fir. Canopy gaps become dominated 

by brush and intolerant species. 

Within the analysis time frame the species composition continues to see decreases in pine species and black 

oak measured in basal area. The continued persistence and proportional increase of species more 

susceptible to fire such as fir and incense-cedar contribute to the generally poor resilience of stands. The 

cumulative effect of the No Action Alternative is large areas dominated by shade tolerant fir and incensecedar.

3-11.4.3 Alternative 2 – Uneven Age Management (Structural Restoration)

The main theme of this alternative is restoration of historic pre-1850 forest conditions using regeneration in 

groups and tree removal using individual tree uneven-aged management. Treatments are design to comply 

with the 2004 SNFPA.

Uneven-aged management and standard and guidelines from the 2004 SNFPA reduce ladder fuels and 

provide additional growing space. Restoration and tree removal propose to restore conditions consistent 

with pre-1850 forest conditions: increase pine and oak species composition, increase proportion of large 

trees, lower tree density. Treatments remove trees and apply prescribed fire. In addition this alternative 

regenerates pine in small existing openings and maintains the growth of trees in existing plantations and 

shelterwoods.

Direct and Indirect Effects

Direct Effects tree canopy cover

Reductions in canopy cover result from tree removal. Canopy cover greater than 50 percent is an important 

habitat component for California spotted owls and Pacific fisher (Verner et al. 1992, Zielinski et al. 2004). 

Maintaining canopy cover over 50 percent is used to compare effects on vegetation between alternatives. In 

addition, canopy density has been shown to have a relationship to fire behavior and severity (Jain and 

Graham 2004). Changes in canopy cover resulting from mechanical and hand treatments are addressed in 

this section. 

General forest and old forest thinning strategies reduce tree canopy cover below 50 percent. Treatments in 

Alternative 2 results in a drop from approximately 1145 acres to 580 acres over 50 percent canopy cover. 

Within modeled fisher rest sites alternative s maintains the most acres above 50 percent canopy cover. That 

is in forest structures important to fisher movement Alternative 2 maintains more acres in dense tree canopy 

cover. Proposed treatments remove only ladder fuels along the edges of these fisher structures and apply 

prescribed fire. A direct effect of this tree removal and prescribed fire is that 10 percent of these fisher rest 

site areas drop below 50 percent tree canopy cover. 

Indirect Effects tree canopy cover

Indirect effects on canopy cover are those that occur as a result of growth or mortality following proposed 

treatments. Action alternatives including Alternative 2 reduce canopy cover on several hundred acres. This 

reduction is the result of both tree removal treatments and underburning. However, trees that remain 

following tree removal reoccupy growing space and increase canopy cover with time. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-33

Acres of canopy cover over 50 percent increases over the thirty-year analysis period following thinning in all 

action alternatives. After 30 years Alternative 2 produces approximately 990 acres with a canopy cover over 

50 percent. 

Should a wildfire enter the project area after the treatments are completed (approximately 10 to 15 years 

after present time) Alternative 2 would retain approximately 910 acres, over 50 percent tree canopy cover.

Direct Effects Insect and Density Resilience

Mechanical and hand treatments have the direct effect of removing trees. In old forest emphasis areas 

suppressed and intermediate trees are removed from the understory to provide for lower fire severity and 

remove fuel ladders. In general forest thinning areas tree removal occurs to mimic pre-1850 forest 

structures- fewer trees, increase the proportion of large trees, increase the proportion of pine and oak 

species, reduce the potential for severe fire. Tree removal in the defense zone of the WUI occurs to reduce or 

eliminate the potential for crown fire. Tree removal will be accomplished using skidders, mechanical 

harvesters, masticators or hand cutting (chainsaws). Cut trees will be transported to the landing, lopped and 

scattered or burned. Tree removal effects stand density and the potential for insect and density induce 

mortality. Within research areas treatments are consistent with research design measures.

SDI is used to compare the risk of insect mortality between alternatives. Benchmarks that correspond with 

35 percent of maximum SDI (on set of increase insect mortality and inter tree competition) and 60 percent 

(imminent risk and lower limit of self thinning) of maximum SDI are identified as thresholds for insect activity 

(Oliver 1995, Oliver and Uzoh 1997, Sherlock 2007). The more acres found over the high threshold the 

greater the potential for insect and density induced mortality. The more acres found below the low 

threshold the greater the resilience to insect and density induced mortality. FVS model results were used to 

assess stand density threshold levels within simulation units. 

The direct effects of Alternative 2 would be to reduce the number of acres above the high density mortality 

threshold. The action alternatives do not eliminate the potential for insect attack or disease. Under 

Alternative 2 approximately 30 percent of treated areas have low index and mortality risk (resilience). 

Alternative 2 maintains the highest insect and density resilience in the Providence Unit and the lowest within 

the Bull Unit.

Modeled results would indicate that the creation of snags important for wildlife habitat would continue 

across the project. This is especially true in fisher rest site clumps and research control areas that are 

maintained at densities above the threshold for imminent insect attack and self thinning. 

Action alternatives reduce tree stress by increasing available water, and in so doing lowering the potential for 

insect attack. This improved tree vigor also occurs for large pine trees (Kolb et al. 1998, Kolb et al. 2007). 

Density reduction does not eliminate the potential for insect attack or self thinning. Insects will continue to 

play a role in shaping stand structure. A study that compared thinned and un-thinned stands of ponderosa 

pine demonstrated an increased resistance to insect attack from thinning over a 32-year study period (Kolb et 

al. 1995). While stand structures will be more open, dense portions of stands will exist across stands: fisher 

rest sites, dense clumps, owl nest buffers, burn only treatments, and research control areas. These individual 

trees and pockets of trees will remain prone to insect attack. Insects will cause mortality creating snags and 

habitat. This is consistent with what has been observed in mixed conifer stands with frequent fire regimes 

analogous to the project area (Maloney and Rizzo 2002). In open mixed conifer stands that have continued 

to experience low intensity fire, similar to what occurred in the project area, insect activity was very low and 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-34

tended to kill large old trees. This loss of old trees occurs because old trees are less vigorous (Kolb et al.

2007), and occurs even though they are well established and have access to water held deep in the soil or 

bedrock (North et al. 2006). 

Indirect Effects insect and density resilience

Growth over time increases tree density and SDI across all stands. Increasing tree density results in higher 

SDI and less areas resilient to insect and density induced mortality (Figure 3-14). Even after growth, the area 

subject to high risk under Alternative 2 remains below current existing levels for the 30 year analysis period.

Insect and density induced mortality will continue to kill pine species at higher rates than white fir and 

incense-cedar.

Tree removal results in the creation of logging residue (slash) and can damage individual trees. Logging 

residue can result in the creation of habitat for pine engravers (Ips species) when young trees less than eight 

inches in diameter are thinned. If slash is created between January to June or when slash does not have time 

to dry, then bark beetles can breed in slash and latter emerge to damage or sometimes kill conifers (Furniss 

and Carolin 1977). Design criteria and forest policy seek to limit the availability of slash for habitat by limiting 

the time when slash is created. In addition, trees damaged during logging are removed to prevent vectoring 

disease and insects. 

Insect attack causing conifer mortality following fire is known to occur. This is true for both wildfire and 

prescribed fire. The relationship between fire and insect attack are not clearly understood. Research has 

most often been done on the interaction of wildfire damage and mortality. Less study has been completed 

on the relationship between prescribed fire damage and insect mortality (Mitchell and Martin 1980, Parker et 

al. 2006). Miller and Keen (1960) described the relationship between crown damage from fire and insect 

mortality. A greater percentage of crown damage results in a greater loss from insect mortality. This 

relationship between crown damage and attacks by western pine beetle has been described by others 

(McHugh et al. 2003, Wallin et al. 2003, Breece et al. 2007). Proposed underburns will generally result in 

crown scorch in high severity portions of burns. Since crown scorch can lead to insect attack and mortality of 

pines, the underburn program can indirectly cause some reductions in canopy cover and the loss of pine 

larger than 24 inches. Model results indicate the loss of trees greater than 24 inches to be less than 1⁄2 trees 

per acre. Observed losses are less than 1/10 of a tree per acre in sampled underburns (Ballard 1999).

Direct Effects on Large Trees, Species Composition and Tree Removals

A direct effect of the tree removal in Alternative 2 is to reduce trees in each diameter class: 0 to 10 inches

DBH, 10 to 20 inches DBH and 20 to 30 inches DBH. Hazard trees larger than 30 inches are removed to 

increase public and fire fighter safety along travel routes and structures. Table 3-11-4 displays the number of 

trees removed by diameter class and percentage remaining after harvest treatment for Alternative 2. 

Alternative 2 removes approximately 33 percent of trees 0 to 10 inches, 20 percent of trees 10 to 20 inches, 

and 8 percent of trees 20 to 30 inches from mechanically treated areas. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-35

Table 3-11-4 Tree numbers for each alternative across all project acres – treated and untreated acres

Alternative 2 -Uneven-aged

DBH Class 0" to 10" 10" to 20" 20" to 30" 30" to 35" over 35"

Existing Trees (1000s of 

trees) 1040 136 53 13 18

Mechanical Treatment 

Tree Removals (1000s of 

trees)

347 27 4 0 0

Percent removal 33% 20% 8% 0% 0%

Percent remaining 67% 80% 92% 100% 100%

Tree removal in intermediate size trees (20 to 30 inches DBH) occurs to meet restoration objectives: 

increasing or maintaining pines and oaks, increasing proportion of large trees, reducing tree density. In as 

much as the removal of small trees reduces the fuel ladders that threaten the persistence of large trees 

during a wildfire event or during underburning, the direct effect is to increase the likelihood that these large 

trees will survive. This is consistent with published research that indicates that understory thinning and 

individual tree selection treatments directly benefit the protection of large trees (Agee and Skinner 2005, 

Kolb et al. 2007). 

Indirect Effects on Large Trees, Species Composition and Tree Removals

The benefits of larger trees and increase pine species are indirect benefits achieved latter in time. 

Restoration of forest structure components require a period free of stand replacing events. These stands 

replacing events kill all trees (larger and small) over dozens to potentially hundreds of contiguous acres. 

The reduction of trees through thinning meets several needs: reduced potential for crown fire, increased 

resistance to insect attack (resilience), and increases proportion of larger trees. The action alternatives 

provide growing space allowing for tree diameter and crown expansion. Stand density and trees size are 

inversely related. Trees grown in low-density stands tend to be larger (Oliver and Larson 1996). In addition 

research by Poage and Tappanier (2002) would indicate that open stand conditions might be necessary to 

grow the large trees that dominated forest under a frequent fire regime. Larger trees are more resistant to 

the effects of fire.

The indirect effect of action alternatives is to provide fewer trees that occupy greater growing space after a 

period of growth. Structural restoration seeks to maintain sufficient 20 to 30 inches DBH size trees to meet 

immediate wildlife needs and recreate low tree density conditions found in the pre-1850 forest. Alternative 

2 retains approximately 92 percent of trees 20 to 30 inches DBH. Figure 3-11-15 displays the increase in the 

proportion of large trees over time for each management unit. Alternative 2 results in higher proportion of 

large trees over time compared to No Action Alternative or approximately the same amount of large trees 

compared to the other action alternatives. The removal of 20 to 30 inch trees does not lead to a bottle neck 

or limit meeting the desire for large trees in the future.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-36

While large trees increase over time, the proportion of trees greater than 35 inches remain below those 

shown in reconstructed stands in the Teakettle Experimental Forest representative of forest structures 

developed under the low intensity frequent fire regimes historically found in the Sierra Nevada prior to 

1850’s. 

Plantations and regeneration openings benefit from thinning by allowing for increased diameter growth and 

conditions suitable for restoration of species composition and tree size. Regeneration of historical forest 

occurred over a prolonged period, and trees grew at low density with little competition for water, nutrients 

and light that leads to competition based mortality (self-thinning); in contrast, after timber harvest or 

disturbance, young stands may develop with high density of trees with similar ages and considerable selfthinning. The results suggest that tree removal is needed in dense young stands where the management 

objective is to speed development of old forest characteristics (Tappeiner et al. 1997). 

The indirect effect of Alternative 2 is to increase the proportion of shade intolerant species by: favoring pine 

and black oak over fir and incense-cedar, and by planting pine in openings. These two treatments result in a 

small increase (2 percent) in pine stem area after 30 years compared to the No Action. White fir declines in 

dominance during the analysis period with Alternative 2. Within the analysis time frame the lack of 

conditions suitable for pine regeneration limits increased proportion of pine species measured in basal area 

for all action alternatives. 

The increases in pine species predicted for the project area, while small, are consistent with research. 

Comparing composition of seedlings less than 30 years of age in mixed conifer stands growing on highly 

productive sites in northern California; Lilieholm et al. (1990) found that ponderosa pine was not present 

under a heavy overstory in unmanaged stands. However, active management to favor shade intolerant 

species in small openings did allow ponderosa pine (intolerant) and sugar pine (intermediate) to persist in 

stands having an 8 to 12 year re-entry cutting cycle. The indirect effect is that while pine dominance 

increases, the increase in pine dominance is limited due to the few openings suitable fire pine regeneration.

Oaks continue to occupy the same dominance (less than one percent of stem area) under all alternatives. 

Direct Effects Regeneration, Brush Openings and Competing Vegetation

Openings and Regeneration

Gaps are by nature small openings in the forest canopy. Past experience indicates that some are distinct and 

can be mapped, most however are small and only found after field review. Gaps are subject to the effects of 

secondary succession; however because of the small size, gaps have more forest edge relative to the 

opening. This results in the neighboring intact forests having a strong influence on the growth of vegetation 

in the gap (York et al. 2004). Existing openings (gaps) created from insect, disease, past harvest or fire 

mortality is the emphasis for regeneration or brush retention. 

The direct effects of Alternative 2 are to locate openings (gaps) and prepare these areas as groups for the 

regeneration of conifers and oaks consistent with the regeneration treatments or treat brush to reduce the 

age class of brush. The variability of existing openings or gaps results in a variable size distribution. Past 

District experience with small opening regeneration is similar to those proposed under Alternatives 2, 4 and 5 

Regeneration openings smaller than three acres dominated past District treatments. The highest proportion 

of past groups is composed of those approximately 1.25 acres. The smallest openings measured were 0.7 

acres. Stephenson’s (1996) and Piirto and Rogers (1996) proposed that the historical distribution of gaps is 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-37

skewed to openings of 1/3 acre. Field review indicates that proposed regeneration treatments would occur 

in approximately 0.3 acre average size of forest openings.

Field review of the project area identified a range of existing openings suitable for regeneration from 0.1 to 2 

acres. Many smaller openings occur, but were not measured. Natural regeneration has occurred in these 

small gaps. Previous planting and natural regeneration in the project area has resulted in conifer 

regeneration in openings ranging from less than one tenth of an acre to two acres.

Existing openings consistent with the design criteria would be planted with approximately 300 to 450 trees 

per acre or 10 to 12 feet between planted seedlings. District records indicate that typical seedling survival 

rates in similar mixed conifer forests are above 80 percent. Rock and other obstructions reduce the total 

number of spots available for planting. Thus a planting spacing of ten feet apart yields 435 gross seedlings 

per acre inside gaps. Typically rock and obstructions limit plantable soil by twenty percent. Eighty percent 

survival and 80 percent plantable soil yields approximately 278 seedlings within a one acre opening. Planted 

existing openings can occupy up to ten percent of stands. Thus planted seedlings will contribute 

approximately 28 trees per acre across any stand. Jeffery pine, ponderosa pine and sugar pine (rust 

resistant) would be planted. Natural regeneration would be allowed and encouraged.

Competing vegetation

Alternative 2 plants conifers, releases planted conifers and thins along the edges of opening to reduce shade. 

In these less shaded conditions the reforestation of openings will favor the survival and growth of pine 

species. As previously discussed, Lilieholm et al. (1990) found that ponderosa pine was not present under a 

heavy overstory in unmanaged stands, active management is often necessary to create conditions for shade 

intolerant (sun loving) pine. The direct effect of Alternative 2 planting in openings, control of brush, and 

reducing edge trees is to create an environment suitable for establishment and growth of shade intolerant 

species. Alternative 2 retains brush in 10 percent of existing openings and retains up to 15 percent brush in 

plantation areas.

Alternative 2 treats bear clover where it competes with planted seedlings in openings. Alternative 2 treats 

competing bear clover by a directed backpack spray of glyphosate + surfactant. Two applications of 

glyphosate have been typically required to reduce bear clover cover below 20 percent. The direct effect of 

this treatment is to kill both the above ground stem and the below ground rhizomes. Bear clover is seldom 

eliminated from an area treated with glyphosate. Grasses often invade areas with reduced cover of bear 

clover and other brush species. Grasses are effective competitors for site resources. The second application 

of glyphosate will also control invading grass species.

Green leaf manzanita, deer brush, and whitethorn are sprouting species and can also germinate from seed 

stored in the soil. Direct effects on ceanothus species and green leaf manzanita are reductions of above 

ground cover through mastication, tractor piling, hand cutting (chainsaws and manual release), and 

underburning. Below ground root systems will be disrupted or killed through tractor piling (brush rake), 

underburning and chemical application. Each treatment has a differing effect on species capable of 

sprouting. Treatments that remove only the above ground stems of sprouting species are ineffective in 

control. However, the above ground removal reduces the size of plants and reduces leaf cuticle thickness. 

Both these results make subsequent chemical treatments more effective. Tractor piling serves to disrupt 

below ground roots. It reduces the mass of roots, but stimulates sprouting. 

Underburning can reduce both the above ground green leaf manzanita stems and below ground roots. 

Underburning however also stimulates sprouting (Kauffmann and Martin 1990). In a study of burning in the 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-38

Sierra Nevada mixed conifer, results indicate that spring burning had the most sprouts, while fall burning 

results in the most plant mortality. Monitoring results from two underburns on the HSRD indicates that 53 

percent and 62 percent of existing brush canopy cover was killed in these burns. However, the typical District 

spring burns are not effective in killing the root systems of sprouting species. Similar results can be expected 

in Alternative 2 and other action alternatives.

Hand cutting is planned for the control of Ceanothus cordulatus seedlings. Manual release of Ceanothus 

cordulatus is ineffective on large plants. Manual treatments are not able to effectively cut plants, and large 

roots simply re-sprout. Manual treatments on Ceanothus intergermis are ineffective and are not planned. 

Alternative 2 treats existing large plants (> 2 feet tall) through cutting or shredding (mastication). Glyphosate 

chemical spraying of ceanothus species is most effective when sprayed on small and tender plants. 

Hand cutting is planned for the control of whitethorn seedlings or where plants are less than 2 feet tall. 

Manual release of whitethorn is ineffective on large plants or large roots. Alternative 2 treats existing large 

plants through cutting or shredding (mastication). A follow up spray of glyphosate + surfactant (R-11) are 

used to kill the large root systems. 

Non-target plant species are likely to be killed by proposed treatments. This is true for both mechanical and 

chemical treatments. Both the mechanical and chemical treatments are proposed for stands that will contain 

a mosaic of both understory vegetation and logging residue. Mechanical treatments while directed at larger 

woody plants and removal of logging residue will tend to treat all brush species found in areas available for 

treatment (outside of streamside management zones, owl nest buffers, and protected brush openings). 

Chemical treatments may also kill non-target species in treated areas. This results from the intermixing of 

target and non-target species. However, past experience and research indicates that non-target species are 

not eliminated from treated stands (McDonald and Fiddler 1995).

Indirect Effects Regeneration, Brush Openings and Competing Vegetation

Thinning will tend to reduce overstory canopy cover. This will result in increased resources for remaining 

trees and increase understory shrub production. Studies on the HSRD (near the project area) of understory 

Ceanothus species volume and overstory canopy cover indicate that brush production is related to both the 

amount of overstory tree canopy cover and the amount of understory brush volume (Kie 1985). Equations 

developed by Kie (1985) indicate Ceanothus brush growth will increase by 35 percent for reductions in 

canopy cover from 60 percent to 40 percent. Ceanothus species growth will increase by 200 percent in 

openings. Increases in growth and cover of manzanita, bear clover and other brush species can be expected 

following the reduction of overstory canopy cover. Site preparation, and release treatments planned for the 

project have proven effective in the control of competing vegetation found in openings and plantations. Site 

preparation, release treatments, and burning will create condition suitable for the invasion of plants that do 

well in disturbed sites or open canopies. These plants that arrive following disturbance include grasses 

(including cheat grass) and other noxious weeds (McDonald and Fiddler, 1989; McDonald, 1986; Larson and 

Schubert, 1969, Keeley 2001). While treatments reduce the cover of site competitors, treatments also make 

conditions for the dominance of sites by conifers (McDonald and Fiddler 1995).

Conifers, Brush and the Need for Herbicides

Using site preparation, planting, release (regeneration openings) and pre-commercial thinning (existing 

plantations, and regeneration openings) treatments, approximately 92 acres of regeneration openings, and 

33 acres of regeneration in a large brush field (plan-id 1043), 418 acres of released existing plantations would 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-39

be maintained or converted to young Jeffrey pine and sugar pine seedlings. Regeneration openings and 

plantations would contain scattered larger trees. These planted seedlings and scattered trees would 

eventually grow large enough to shade out many of the competing brush and grass species in approximately 

15-25 years. Reforested montane brush openings would be single storied even-aged stands. Existing 5 to 15 

year old plantations would continue to be single storied. Older plantations with openings would receive new 

planted pine; this would create a second or third age class. Genetic variation would also be reintroduced 

from seed collections within the local seed zone and growing and planting these conifer and rust-resistant 

sugar pine seedlings within the project area. Species composition would include a mix of planted conifers 

(Jeffrey pine, lodgepole pine, and sugar pine) and natural regeneration. Natural regeneration would include 

incense-cedar, white fir and oaks. Stand development from early brush dominance to conifer dominance 

would be accelerated over natural stand succession rates.

Conifer growth would be slowed in regeneration opening as a result of both scattered large trees in the 

openings and adjacent edge trees. Research results indicate that overstory trees tend to suppress the growth 

of understory seedlings and the more trees remaining resulted in more reduction of growth (McDonald 1976, 

Birch and Johnson 1992). Edge trees reduce the growth of trees in small group openings. Studies of the 

growth seedlings in small group openings indicate that trees closer to the edge experience the most 

reduction in growth (York, Battles and Heald 2004) and smaller openings tended to reduce height growth of 

seedlings more than larger openings (McDonald and Abbott 1994). However, large trees from the existing 

stand along the edge of a group may experience increased growth (York, Battles, Heald, York 2004). This 

additional growth may contribute to total stem volume and tree size for a stand, but it is uncertain if this will 

offset losses from small trees in the regeneration openings. 

While scattered overstory trees and edge trees may reduce the growth of planted and natural seedlings, the 

reduced solar radiation from these trees may benefit the initial establishment of white fir and incense-cedar 

(Erickson et al. 2005). Other species such as shade intolerant species such as Jeffrey pine may experience 

lower survival in these shaded conditions (Erickson et al. 2005). In openings with few large trees Alternative 

2 will favor pine and oak species. In openings with scattered overstory trees the effect of Alternative 2 will be 

to favor the establishment of fir and reduce the survival of shade intolerant pine species. The result of 

implementing Alternative 2 will be to create conditions that result in the establishment of mixed species 

groups of shade intolerant pine and shade tolerant true fir and incense-cedar with adjacent and scattered 

larger trees that will slow the growth of natural and planted seedlings. 

a. Bear clover

In a dense forest, bear clover is found at low densities beneath the overstory. Bear clover can fully occupying 

openings. Ground disturbing activities (harvest, tractor piling, and mastication) and burning may crush or 

reduce above ground stems, but the rhizome type root system remains intact and can readily take advantage 

of increased sunlight and nutrients. A ground application using backpack sprayers of glyphosate + surfactant 

will reduce the cover of both the above ground and below ground rhizomes. A review of Forest Service 

experience in non-chemical vegetation control (Click et al. 1988; Click et al. 1994) and local SNF experience 

indicates that chemical applications are the only effective way to insure reforestation objectives are met. 

Research indicates that effective treatments are those that kill bear clover rhizomes, and herbicides such as 

glyphosate are effective, while hand, fire and mechanical methods are not effective control treatments 

(Tappenier and Radosevich, 1982, McDonald et al. 2004). In local environments, treatments such as the 

winged subsoiler and repeated fire at the time of flowering have been suggested for control, but have not 

proven effective. Fire, hoeing, and machines have been used on the SNF to remove the above ground portion 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-40

of bear clover; due to the rhizome type root system sprouting of plants occurred soon after treatment. 

Sprouts quickly reinvaded these treated areas. Survival of planted seedlings was well below desired stocking 

levels. Herbicides application has proven the only effective means to control bear clover on the SNF. These 

results agree with reforestation research that indicates that after three years, only 13 percent of the conifers 

planted were alive in a study area with bear clover cover of less than 40 percent (Tappenier and Radosevich, 

1982). This contrasts with 71 percent survival in areas with temporary control of bear clover. Over a 19-year 

span, only nine percent of the trees planted in an area with no vegetation control survived. Growth of the 

surviving seedlings is also impacted. In the same study, three-year-old seedlings with no bear clover 

competition were twice as tall as the seedlings with no vegetation control. A review of bear clover control 

measures by McDonald et al. (2004) also indicate that treatments that kill bear clover rhizomes such as 

herbicides are the only effective control measure, while other treatments have been failures.

b. Ceanothus and Manzanita

Whitethorn is the most abundant ceanothus species, but deer brush and buck brush are also present. 

Ceanothus species in existing openings are well established and have deep root systems. Ground disturbing 

activities (underburns, tractor piling, hand cutting and shredding) can stimulate sprouting of ceanothus 

species. They also create conditions that allow chemical or subsequent hand treatments to be more 

effective. Treatments that reduce the size of plants also increase the susceptibility of plants to chemical 

applications by decreasing plant size, disrupting root systems, and reducing the thickness of leaf cuticle 

allowing for better penetration of chemicals. Mechanical treatments designed to disrupt the root systems of 

whitethorn make subsequent chemical release treatments effective. Subsequent hand release treatments 

are then focused on brush seedlings. Experience on the Sierra National Forest has shown that large plants 

greater than two feet tall cannot be controlled using hand methods. This is due to the size of the rooting 

system. Whitethorn seedlings have been successfully controlled using hand methods. However, once 

growth of above ground whitethorn plants exceeds two feet, rooting systems are beyond the effectiveness of 

hoes or axes used to remove brush seedlings. In addition, the removal of whitethorn results in the dominance

of grasses and forbs that also compete for site resources. These same results have been observed in other 

Forest Service Ranger Units where repeated hand release treatments have resulted in limited control of 

ceanothus seedlings, impractical control of well established (>2 feet tall) Ceanothus, and ineffective control 

of those that establish from burls or roots (Click et al..1994, McDonald and Fidler 1995).

In other studies, ponderosa pine growing in the middle of Ceanothus and manzanita had a diameter and

height growth of 60 to 90 percent when compared to trees free to grow from competing brush species 

(Oliver 1979; McDonald and Oliver 1983). In another study, without release from ceanothus brush, conifers 

are at a disadvantage in capturing adequate resources and establishing dominance. In the control plot 

(without vegetation management), McDonald and Fiddler (1989) noted that the average height of Ceanothus

was 184 percent greater than that of conifer seedlings. Though seedlings may persist under a canopy of 

Ceanothus, growth would be very slow. In a study that looked at the release of white fir from Ceanothus and 

green leaf manzanita California white fir survival and height, diameter, and foliar cover growth were all 

enhanced by early chemical release followed by follow up hand release treatments (McDonald and Fiddler 

2001). In a companion study McDonald and Fiddler (1997b) found that chemical release with follow up hand 

treatments significantly increased the height and survival of fir over hand treatments or delayed treatments. 

In another study with green leaf manzanita and Ceanothus McDonald and Fiddler (1997) found that 

ponderosa pine crown cover in the chemical treatment was significantly larger than in the no treatment and 

mechanical only treatments, increasing by 104 percent over the control and 42 percent over the mechanical 

treatment alone.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-41

Early medium and heavy cover of Ceanothus and green leaf manzanita have long term effects on conifer 

growth (McDonald and Abbott 1997). McDonald and Abbott (1997) found that ponderosa pine with 

moderate brush cover (15 percent cover) five years after establishment and heavy brush cover (21 percent) 

five years after establishment did not allow planted pine two meet growth standards similar to those in the 

KREW Project area. In addition, heavy brush predisposed ponderosa pine to increased insect attack. In 

contrast, Oliver and Uzoh (2002) found little diameter and only modest height growth with reductions in 

understory brush cover under saplings size fir. Most of the height growth increases occurred in the first five 

years. Oliver and Uzoh (2002) findings are in contrast to McDonald and Fiddler (1997) results that found a 

significant difference in survival and height after 10 years between the chemical release treatments and 

control treatments. 

The experience on the SNF controlling Ceanothus species has been consistent with published information. 

On stands with in the HSRD, part of the Big Sky timber sale 1992 and Big Creek Fire Recovery 1994, hand and 

mechanical means failed to control ceanothus. In the case of the Big Creek Fire recovery conifer 

reestablishment efforts, forest stands were severely burned, salvage logged, planted and hand released. 

Hand release areas dominated by sprouting ceanothus species had more than 50 percent cover in brush and 

planted and natural seedlings smaller than adjacent areas without sprouting species. In the case of the Big 

Sky treatments large Ceanothus (> 4 feet tall) was cut with chainsaws. Observations in the following year 

showed ceanothus sprouts to be two and three feet tall.

Ceanothus and manzanita have many morphological and physiological adaptations that allow them to 

capture resources, growing rapidly after major disturbances. One adaptation is the ability for some 

Ceanothus species to fix nitrogen. While soil nitrogen is beneficial for seedling growth and varies beneath 

Sierra Nevada vegetation gaps (Erickson et al. 2005), brush cover removes soil moisture needed for seedling 

survival (Gray et al. 2005). Brush cover may benefit the establishment of shade intolerant species (white fir, 

incense-cedar and red fir), however the overall benefit for growth of these species was undetermined in the 

Erickson et al. (2005) study in the Teakettle Experimental Forest. Results from the Teakettle Experimental 

Forest suggest that reductions in shrub cover may benefit tree establishment, but increasing understory light 

and decreasing surface soil moisture through overstory canopy cover reductions may not. 

Green leaf manzanita (Arctostaphylos patula) sprouts from the roots in response to disturbance similar to 

ceanothus. Manzanita plants in openings and plantations exceed three feet in height. The size of these 

plants makes hand removal impractical. Manzanita and Ceanothus competition was responsible for a 58 

percent reduction in growth in a 20 year old Sierra Nevada Ponderosa Pine stand (Oliver, 1990). Once 

manzanita seedlings begin to grow, they can rapidly occupy a site after disturbance. Ground disturbing 

activities will affect green leaf manzanita similar to ceanothus species. 

The indirect effects of Alternative 2 on sprouting brush species are to free site resources for the growth of 

conifers.

The single strongest factor affecting planted tree growth in the detailed long-term soil productivity 

experiment was understory brush cover (Powers et al. 2004). In the Sierra Nevada, where summer drought is 

common, planted tree productivity averaged more than three times higher in the absence of understory 

vegetation (Powers et al. 2004). The long history of reforestation on the Sierra National Forest, research that 

has examined the growth of conifers with and without brush competition suggests that the indirect effect of 

Alternative 2 on Ceanothus and manzanita species will be to free site resources for the growth of conifers. 

Based on the morphological characteristics that promote sprouting, the history of ineffectiveness of hand 

control of Ceanothus and manzanita, the large body of research that indicates the manzanita and Ceanothus
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-42

are strong competitors with conifers for site resources - herbicides are essential for the control of competing 

vegetation.

The indirect effect of site preparation and release treatments is to create conditions within regeneration 

openings and existing plantations that meet the objectives of conifer establishment, survival and accelerated 

growth in Alternative 2. 

Direct Effects Prescribed Fire and Wildfire Severity

Underburning is conducted to reduce the amount of fuels on the forest floor under a managed prescription. 

The burning prescription will be conducted so that low intensity fire will move through the stand. Flame 

heights should be less than two feet. Underburning will occur alone or after logging residue is removed, 

tractor piled, lopped/scattered, or masticated. 

Several stand structure components are affected by prescribed burning; overstory trees, understory trees, 

brush, snags, and logs. The direct effects of underburns on trees have been monitored for the HSRD. 

Monitoring has been extensive- with fuels management personnel classifying fire severity (high, moderate, 

low) across underburns; and intensive - sampling with plots quantifying the amount of mortality of trees and 

brush. Prescribed underburns in Alternative 2 and other action alternatives are designed to have similar fire 

behavior as previous underburns across the HSRD. Fire severity classes represent the direct effects from 

prescribed fire and not effects associated from insect mortality. Crown scorch and loss in basal area was used 

as the measure of fire severity. Scorch heights and thus the direct effects on vegetation from action 

alternatives should fall within the range of severity experienced during previous District prescribed fire 

treatments. 

Model results indicate that underburns will kill less than one tenth of a tree per acre over 30 inches DBH. The 

HSRD has currently approximately 17,300 acres in an underburning program. Underburns (prescribed fire) 

have been accomplished in ponderosa pine, sierra mixed-conifer, montane hardwood conifer, montane 

hardwood, and montane chaparral CWHR types. Fire severity examined in terms of tree and brush mortality 

has been monitored intensively on two burns and severity categorized for other burns on the District using 

scattered monitoring plots and observations from burn bosses (McCandliss 1998). Severity is divided into 

low, medium and high direct effects of fire mortality. Low fire severity is composed of fire scorch less than 15 

feet tall. Most trees taller than 15 feet will survive. Low severity areas will experience less than 10 percent 

reduction in basal area. Dominant tree crowns over 15 feet will appear green or unburned. Medium severity 

fire will result in 15 to 50 foot scorch height. Ten to 50 percent of existing basal area may be lost. Many 

trees will have brown needles. High severity areas will have scorch height greater than 50 feet. More than 

50 percent of the basal area will be lost. High severity areas will have blackened crowns and brown crowns. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-43

Observations of underburn severity from previous underburns are displayed in Figure 3-11-8. Model results 

indicate that underburning will result in less than five percent high tree mortality. A detailed examination of 

the mortality experienced during the Barnes mountain burn (ponderosa pine type) indicates that 53 percent 

of existing brush covers was killed during burning (Ballard 1999). Tree mortality was largely confined to trees 

less than 5 inches DBH in one portion and 11 inches in another portion, however, one tree over 43 inches 

DBH died as a result of both fire and insect activity. The HSRD underburn severity is in contrast to severity 

experienced during prescribed fire at Sequoia and Kings Canyon National Park that neighbors the SNF. 

Intensive monitoring of one prescribed fire in the Park indicated that as much as ten percent of dominant 

trees were killed by both fire and insects (Mutch and Parsons 1998). The character of fire severity differs 

between the SNF and neighboring National Parks for several reasons: 1) Park objectives are often to create 

openings and kill trees less than 31 inches DBH (Kiefer 2000), while the Forest objectives are to consume 

ground fuels and kill trees less than eight inches in diameter and brush, 2) the Park objectives drive 

prescribed fire prescriptions with flame lengths over two feet, while Forest objectives drive fire prescriptions 

with flame lengths less than two foot.

The severity experienced from the underburn program in the HSRD is consistent with model results and 

research results. Research results indicate the mortality is affected by season of burn and fuels conditions 

(Knapp et al. 2006, Knapp and Keeley 2006). Model results for underburns indicate that some forest areas 

experience high understory mortality and little overstory mortality, while other areas or pockets of moderate 

overstory mortality. This moderate mortality could be seen as small pockets (less than one acre) of dead 

trees scattered across burn areas (McCandliss 1998). Rarely larger pockets would result from the 

combination of both insects and fire.

Proposed prescribed fire treatment will fall within the range of severity experienced in previous burns. 

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

High Sierra District 

Prescribed Burn Severity

Past Prescribed fire Projects

low moderate high 

Figure 3-11-8: Prescribed fire severity of past project underburns by vegetation type
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-44

Modeling and experience indicate that underburns tend to be of low severity for overstory trees, kill most 

trees less than 8 inches DBH, and kill high proportions of above ground brush stems. Monitor results of the 

Barnes south and Barnes north underburns indicate that less than three overstory trees (larger than 20

inches DBH) were killed over several thousand acres. 

Large woody debris provides important wildlife benefits. While HSRD underburns consume ground fuels, not 

all large fuels (logs) are consumed in fires. The survival of logs during underburning varies based on fuel 

moisture, surface fuel loading, and topography. Monitoring results from the Barnes South underburn 

indicate that post burn; there were 16 logs per acre greater than 10 inches large end diameter. Seven of 

these logs were greater than 16.0 inches. Underburns in Alternative 2 should result in similar numbers of 

logs. 

Recent research analyzing the effects of prescribed fire on the High Sierra Ranger District indicates that a 12 

percent loss of large snags (greater than 22 inches DBH) was experienced in both mixed conifer (Innes et al.

2006) and ponderosa pine stands (Bagne et al. 2008). This same research indicates increases in smaller snags 

of over 25 percent. See Fire and Fuels subsection 3-3. These results reflect short term direct effects from two 

burns. It is expected that while short term effects on large and small snags may be similar, long term 

mortality will likely result in little change or an increase in large snags resulting from prescribed fire.

Indirect Effects Prescribed Fire and Wildfire Severity

Since wildfire mortality occurs during and subsequent to a wildfire event, treatments conducted under 

Alternative 2 have no direct effects on wildfire severity. This analysis describes the effects of treatments on 

wildfire severity and planned prescribed fires. Effects on wildfire tree mortality occur at a different time and 

are thus indirect effects. Forest and fuels specialists can provide probabilities associate with the risk of a 

wildfire. This assessment assumes that a wildfire will start. Severe wildfire behavior is modeled at the 97th

percentile weather conditions. Without maintenance treatments, the indirect effects from treatments on the 

behavior of a wildfire lessen as time passes. High severity wildfire occurs when 75 percent of tree stem area 

is killed. Low mortality occurs when less than 25 percent of tree stem area is killed.

Post treatment mortality from a potential severe wildfire is less for Alternative 2 than the No Action (FVS 

results). Figures 3-11-16 displays the changes in wildfire severity following treatments for the project. These 

model results indicate that treatments reduce the proportion of the project subject to high mortality. This 

effect on high mortality lessens with time and no additional maintenance treatments. However, prescribed

fire each decade for 30 years is planned for all action alternatives. This results in continued effectiveness of 

original treatments.

While Alternative 2 replaces brush with conifers (plantations and existing openings), the benefits of reduced 

brush and increased conifers are not realized until conifers become larger and more resistant to fire. In time 

these trees become more resistant to wildfire. 

Alternative 2 has several treatments that are designed to alter surface, ladder and crown fuels. Surface fuel 

treatments include tractor piling and burning logging residue as well as brush, hand piling and burning of 

logging residue and brush, mastication of brush and small trees, lopping and scattering of logging residue and 

underburning. Ladder fuel treatments include reducing the numbers of small trees and brush. Crown 

treatments include increasing the space between crowns through thinning. The modeled results of these 

treatments are consistent with both other modeled results that show reduced severity following treatments 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-45

over untreated stands (Hollenstein et al. 2001, Stephens and Moghaddas 2005) and the results from actual 

severe fire following treatments (Pollet and Omi 2002). 

Modeled results of Alternative 2 are also consistent with studies that indicate that leaving logging residue 

under crowns (lop and scatter of logging residue) will result in more severe fire mortality (Stephens and 

Moghaddas 2005). These studies and others, also indicate that patterns of severity result from both the 

amount of fuels treatment that remove or consume fuels and fire conditions. Alternative 2 treatments 

combine the removal of small and intermediate size incense-cedar and white fir to break the link between 

understory fuels and upper canopies (fuels ladders). However, research design delays fuels burning in 

“mechanical only treatments” (210 acres). These understory fuels ladders increase the potential for torching 

and crown fire. Intermediate size trees 20 to 30 inches DBH trees are removed in part: (1) reducing canopy 

bulk density to reduce and eliminate when possible crown fire spread (Stephens and Moghaddas 2005, 

Safford et al. 2009) in stands treated in the WUI, (2) decreasing intermediate-sized ladder fuels that have 

continuous fuels to the ground (North et al. 2009). 

Direct Effects on Forest Restoration

The Alternative 2 treatments incorporate structural restoration treatments design to achieve pre-1850 

conditions. KREW treatments as whole mimic structures developed under frequent fire regimes: increased 

dominance of large trees, increase the dominance of sun loving (shade intolerant) pine, creates forest tree 

density resistant (resilience) to disturbances such as wildfire, and insect attack. 

The greatest direct effect is achieved through dramatic reductions in the effects of wildfire and in particular 

high severity fire. Alternative 2 and other action alternatives result in reductions in acres subject to stand 

replacing fire. This reduction in fire severity is critical to restoration (North et al. 2009). This result occurs 

after treatments are completed. Alternative 2 has fewer acres subject to high severity fire compared to the 

No Action alternative. 

Alternative 2 and other action alternative reduce tree numbers over 11 inches DBH. Desired conditions 

attempt to mimic tree numbers per acre in pre-1850 forests, but not strictly represent past forest conditions. 

Alternatives that reduce tree numbers consistent with the desired conditions are closer to meeting 

restoration desired conditions. Eighteen of the 29 stands move closer to the desired condition under 

Alternative 2 (Figure 3-11-9). Three stands achieve approximately the same movement toward desired 

conditions in both action alternatives. Alternative 2 tree removal achieves tree numbers (> 11 inches DBH) 

closer to the desired condition; the direct effects on achieving restoration:

Alternative 2 reduce tree numbers per acre. 

Alternative 2 increases fire resilience 

Alternative 2 increases in insect and density resilience 

Alternative 2 results in lower landscape heterogeneity following treatments (see Figure 3-11-17).

Seven stands achieve the structural restoration targets for tree density and eighteen move closer. 

As a result of the above in direct effects, Alternative 2 has a greater resistance to change and as a result 

greater resilience compared to the No Action.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-46

Indirect Effects on Forest Restoration

Over the course of the restoration analysis period Alternative 2:

Increases the proportion of large trees from 31 percent to 55 percent of stem area

Increases the proportion of pine species from 21 percent to 23 percent

Increases resilience to severe fire from approximately 320 acres to 1600 acres in treated area (Figure 

3-11-16) 

Increases resistance of trees to density induced mortality and insect disturbance from 12 percent to 

30 percent of treated acres in the Providence Unit and from 21 percent to 37 percent in the Bull Unit 

(Figure 3-11-14).

Cumulative Effects 

Cumulative effects are those activities that additively contribute to cumulative impacts on canopy cover, 

large trees, conifer establishment, resistance to high severity fire, resistance to insect attack, and ecological 

restoration conditions from Alternative 2 and past, present and reasonably foreseeable activities. These 

activities include plantation maintenance, past timber projects, vegetation management, fuels reduction, 

prescribed fire, roadside hazard tree removal, and power line maintenance. In addition, residential 

development, timber harvesting, and vegetation management is carried out on private land holdings 

adjacent to the project. 

0

20

40

60

80

100

120

140

208235236250280281292295299301306316331346365380449450499796811838961962964965

104310561057

Trees per Acre > 11"

Stand Number

Alternative 2 Desired Condition vs Post Treatment

Trees per acre Remaining Trees per acre removed

Desired Condition Canyons Desired condition Ridges

Figure 3-11-9 displays the desired condition for trees per acre and the post treatment trees per acre for 

alternative 2
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-47

Cumulative effects on vegetation are examined with adjacent restoration and research projects (4,900 acres) 

that include the Providence Unit, Dinkey South, and Dinkey North project areas. In addition, cumulative 

effects are analyzed across a large landscape (72,000 acres) that includes three large watersheds 

encompassing coniferous forests adjacent to the KREW Project area. Changes to vegetation composition and 

structure are examined from past, present, and reasonably foreseeable activities. 

Activities with no cumulative effect on vegetation

The following treatments have no cumulative effect on vegetation: 

Road maintenance treatments do not effect sufficient vegetation to create a detectable change in 

vegetation from existing conditions. 

Cattle grazing may affect vegetation locally were cattle are gathered. Cattle do not typically eat 

brush or trees. Thus a cattle grazing has no detectable effect on brush and tree vegetation growth. 

As a result there is no potential for cumulative effect. 

The Jose basin fuels reduction project occurs outside the cumulative effects boundary for vegetation. 

This results in no potential for cumulative effect on vegetation.

Travel by recreationists on designated travel results does not change vegetation. Thus 4x4, OHV and 

snowmobile travel has no potential for a cumulative effect on vegetation.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-48

Table 3-11-5 summarizes the effects on vegetation of past, present and reasonably foreseeable actions.

Project or 

Activity Description

Past, Present, or 

Future Action Effects on vegetation structure and growth 

Plantation 

maintenance

Thinning, hand 

release, chemical 

release, planting in 

plantations less 

than 25 yrs old

Past, present and 

reasonably 

foreseeable

These projects clear unwanted brush and thin 

trees. They have the effect of increasing tree 

growth, tree vigor, and reduce the potential for 

high intensity wildfires. The cumulative effect is 

to increase the area dominated by large tree 

structures and reduce the area subject to 

severe fire 

Roadside hazard 

tree removal

Removal of hazard 

trees along roads,

Past, present and 

reasonably 

foreseeable

These treatments remove damaged or dead 

trees along roads and near structures. The 

effect is to reduce the approximately 700 large 

old decadent trees per year across the 72,000 

acre cumulative effects boundary. 

Restoration Dinkey North and 

Dinkey South 

Present The proposed treatments would reduce tree 

density and increase resistance to fire and 

insect mortality. The cumulative effect would 

be to create a large area with greater resistance 

to severe fire and insect attack. 3,000 acres

NF timber sales Past timber 

management 

projects, (Dinkey 

South) 

Past and reasonably 

foreseeable

Past timber sales have finished all treatment 

activities (thinning, piling, and burning) and are 

considered part of the current condition in 

relation to vegetative structure. There is no 

cumulative effect from these projects. 3,000 

acres. 

Prescribed fire Underburning to 

reintroduce fire 

and reduce ground 

fuels

Past, present and 

reasonably 

foreseeable

These projects may prevent wildfires from 

moving into the Dinkey North project area. The 

cumulative effect would be to increase the area 

with a vegetative structure with increased 

resistance to severe fire. Approximately 3,000 

acres per year

Fuels reduction Jose 1, 10S18, 

South of Shaver 

thinning, and 

prescribed fire

Past There is no cumulative effect from these 

projects. 

Vegetation 

management -

SCE

Uneven-aged 

thinning, Rx 

burning, 

reforestation, 

restoration 

treatments 

Present These projects reduce tree density and increase 

resistance to severe fire and insect attack. 

These projects may also reduce the number of 

trees > 30”. State forest practice act allows for 

removal of large trees. 1,000 to 1,500 acres per 

year

Vegetation 

management –

PG&E 

transmission line

Right-of-way 

maintenance

Present This project is part of the existing vegetation 

condition. Approximately 300 acres a year

Vegetation 

management

Twin Ponds 

emergency plan 

for removing dead, 

Present This emergency plan will remove dead and 

dying trees. The project will reduce the number 

snags across the cumulative effects boundary.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-49

Project or 

Activity Description

Past, Present, or 

Future Action Effects on vegetation structure and growth 

dying, and 

diseased trees

Vegetation 

management

Dogwood and 

Ridgetop 

subdivisions 

timber harvesting, 

Sierra Music and 

Arts Foundation 

Management Plan

Past and present There is no cumulative effect from these 

projects. They are outside the cumulative 

effects boundary for vegetation

Vegetation 

management

Camp El-o-win Past This project removes small trees near structures 

on less than 10 acres of actual treatment. 

There is no cumulative effect. 

Vegetation 

management

Wildflower 

subdivision, 

timberland 

conversion

Past There is no cumulative effect from these 

projects. They are outside the cumulative 

effects boundary for vegetation

Livestock grazing Grazing in the 

Dinkey allotment

Present and 

reasonably 

foreseeable

There is no cumulative effect from this project.

Road 

maintenance

Grading and 

cleaning culverts in 

Kings River area

Past, present and 

reasonably 

foreseeable

There is no cumulative effect from these 

projects.

Motorized 

recreation 

4x4, OHV, and 

snowmobile travel 

on designated 

routes

Present and 

reasonably 

foreseeable

There is no cumulative effect from these 

projects.

Providence Unit (KREW), Dinky South, Dinkey North and private forest treatments treat a gross area of 

approximately 4,900 acres. These proposed projects are found adjacent to each other and result in 

approximately 1,400 acre reduction in tree canopy cover over 50 percent. This is a direct cumulative shift 

locally of approximately 30 percent of the area to more open tree canopy conditions. 

Across the (72,000 acres) cumulative effects boundary Alternative 2 and current and reasonably foreseeable 

actions result in a direct cumulative three percent reduction in acres with tree canopy cover over 50 percent. 

Table 3-11-5 summarizes the cumulative effect from present, past and reasonably foreseeable projects that 

may have a cumulative effect on vegetation.

Alternative 2 Providence Unit, Dinky South, Dinkey North and private forest treatments will reduce stand 

density and increase tree vigor. The cumulative effect across the local scale (4,900 acres) is to increase the 

resistance to insect attack and density induced tree stress. Prior to treatments there are approximately 2,100 

acres at high risk to insect or density mortality; this is approximately 40 percent of the 4,900 acre local scale 

effects area. Following treatments of proposed projects this results in approximately 860 acres still subject to 

density induced mortality or approximately 20 percent of the 4,900 acre local scale cumulative effects area.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-50

Across the larger (72,000) landscape approximately one third of the landscape is subject to high risk to insect 

or density mortality. The result of all present, proposed and reasonable foreseeable actions across the larger 

landscape is to reduce acres at high risk to insect and density mortality by 2,300 acres. However, tree growth 

and the resulting increased density across the 72,000 acres results in an overall increase in the area subject 

to high risk to density induced mortality after only 5 years. The resulting cumulative effect on density 

mortality is across the larger scale analysis area is to slow the rate at which acres of conifer forest move 

toward high risk, but treatments are small compared to the larger landscape. 

Modeled results indicate the current population of trees larger than thirty inches diameter at breast height at 

approximately 470,000. Current and proposed hazard tree, residential development and power line 

maintenance treatments remove approximately one thousand trees greater than thirty inches across the 

72,000-acre forested landscape. After implementation of Alternative 2, proposed and current activities, 

trees larger than thirty inches are reduced by less than one half of a percent across the landscape. This is the 

same for both the No Action and all action alternatives.

Timber harvests on Southern California Edison lands would also reduce tree numbers of trees larger than 

thirty inches. While it is unclear how much these treatments on private lands would reduce large tree 

numbers, typical prescriptions can remove as much as one third of each tree size class (personal conversation 

with SCE managers). Mixed conifer forest on federal lands near Southern California Edison lands contain 

approximately six trees per acre larger than 30 inches DBH. A typical 1,000 acre timber harvest off of private 

lands could remove as much as two trees per acre or about 2,000 trees greater than thirty inches diameter 

breast height. The cumulative effect of all these treatments would be less than a one percent change in tree 

numbers greater than thirty inches across the 72,000 acre analysis area. 

The cumulative effect of Alternative 2, Dinky South, Dinkey North, and private forest treatments is an 

increase in large tree dominance ( >35 inches DBH) after 30 years. The indirect cumulative effect at the local 

scale (4,900 acres) after 50 years is to create a large area with approximately 12 percent more large trees 

than the No Action Alternative and about the same as the other action alternatives. However, these 

treatments have little direct effect on increasing (< 1 percent) over the larger 72,000 acre cumulative effects 

boundary. 

The direct cumulative change to pine species dominance across neighboring projects would see a 3 to 5 

percent increase in pine species over 4,900 acres. The pine dominance as measured by stem area within 

local (4,900 acre) cumulative effects area results in an area of higher pine species. Similar or smaller changes 

would occur in current, recent past and reasonably foreseeable actions across the larger 72,000 acre 

cumulative effects boundary. The exception to these increase are plantations treatments that are already 

dominated by pine. Increasing pine dominance increases resistance and resilience to severe fire since pine 

species are more fire resilient in treated areas. 

However untreated areas dominated by fir and incense-cedar would continue to accumulate stem area and 

favor the production of incense-cedar and fir. The growth of incense-cedar and fir across the 72,000 acre 

would result in cumulative net increases in shade intolerant fir and incense-cedar dominance. 

No landscape model exists for brush and grass growth and response to treatment. Cumulative effects are 

surmised from stand level effects. Brush cover in the 371 acre power line right of way will remain unchanged 

for the analysis period. Brush cover in the housing developments and private forestlands will change along 

with the adjacent restoration project area as a result of overstory growth, tree removal, and brush control. 

Private land owners typically do not control brush (personal communication with Grand Bluffs and SCE 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-51

managers). The cumulative effects on conifers and competing vegetation are connected to changes in brush 

and tree open canopy cover. Changes to brush age and tree removal are expected under Alternative 2, 

adjacent restoration projects, private forest land management (SCE and Grand Bluffs), housing development 

and plantation maintenance. Young brush seedlings may see an increase across restoration projects and 

private forest lands as treatments open space between crowns. As crowns open existing brush will grow 

taller and new brush seedlings will be stimulated to grow. As trees recapture growing space made available 

after thinning and restoration treatments, trees crowns will grow closer together. The increased crown 

canopy cover that results from growth will tend to reduce understory brush cover. This opening of crowns 

with treatment and closing due to subsequent growth will occur with both private and federal present and 

foreseeable projects. 

However, the additive cumulative effect on understory vegetation across the 72,000 acre cumulative effects 

boundary is likely to be a shift in species composition and a lowering of the amount of understory cover. This 

reduction in brush cover results from increases in tree density (that suppresses brush growth) and due to 

underburns, private land treatments, release and site preparation that reduce brush cover. 

Past present and reasonably foreseeable activities reduce the potential effects of wildfire. As restoration, 

fuels reduction, plantation maintenance private forest management treatments occur, the cumulative 

reduction in fire severity may reduce the potential for a large landscape fire (Collins et al. 2010). Total 

proposed and current treatments with an objective to reduce fire severity are approximately 7,600 acres or 

approximately eleven percent of the 72,000 acre cumulative effects boundary. Collins et al. 2010 suggest 

that 1 to 2 percent treatment per year across a large landscape (20 to 30 percent total landscape treatments) 

is needed to strategically reduce high severity large fires. 

The cumulative effects of large-scale treatments, like one project area, are not completely understood (Agee 

and Skinner 2005). While Alternative 2 or the other action alternatives alone create stand conditions that 

result in lower fire severity across stands or the whole project area, these relatively low severity conditions 

could be overwhelmed by high intensity fire in adjacent stands. These results are consistent with observed 

wildfire effects for treated verses untreated stands (Agee and Skinner 2005). Model results indicate that 

treatments expected from proposed and reasonably foreseeable activities will lower severity. However, 

recent research (Collins et al 2010) indicates that insufficient acres are treated by proposed and reasonably 

foreseeable actions to disrupt large severe wildfires. 

3-11.4.3 Alternative 3 – Fuels Reduction

The main theme of Alternative 3 is the reduction of fire severity while maintaining tree canopy cover across 

the project area above 50 percent and limits tree removals to less than 20 inches DBH. The 2001 Framework 

alternative provides a comparison of effects against the No Action Alternative as the baseline and 

alternatives that address restoration (Alternatives 2, 3 and 5). Alternative 3 includes maintenance of existing 

plantations and shelterwoods while not using chemical treatments. Tree planting does not occur in this 

alternative.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-52

Direct and Indirect Effects

Direct Effects Tree Canopy Cover

Defense zone, General forest and old forest thinning strategies reduce tree canopy cover below 50 percent. 

Treatments in Alternative 3 results in a drop from approximately 1,145 acres to 680 acres over 50 percent 

canopy cover. 

Within modeled fisher rest sites Alternative 3 drops approximately 1/3 of the fisher rest sites below 50 

percent tree canopy cover. That means, in forest structures important to fisher movement Alternative 3 

reduces acres in dense tree canopy cover. Proposed treatments remove understory trees and some middle 

story trees to achieve the desired conditions. 

Indirect Effects Tree Canopy Cover

Acres of canopy cover over 50 percent increases over the 30 analysis period following thinning in all action 

alternatives. After 30 years Alternative 3 produces approximately 990 acres with a canopy cover over 50 

percent. 

Should a wildfire enter the project area after the treatments are completed (approximately 10 to 15 years 

after present time) Alternative 3 would retain approximately 940 acres over 50 percent tree canopy cover.

Direct Effects Insect and Tree Density Mortality - Resilience

Immediately following mechanical tree removal treatment the fuels reduction alternative increases from 15 

percent resilient to insect or density induced mortality to approximately 35 percent of the project area (low 

risk is 35 percent of max SDI). 

Indirect Effects Insect and Tree Density Mortality - Resilience 

As with other alternatives, growth increases stand density over time. Pretreatment approximately 15 

percent of project acres are resilient or at low risk to density induced mortality. Increases in stand density 

result in decreases in acres resilient to insect or density induced mortality. With growth, acres resilient (low 

risk) to insect or density induced mortality decreases from approximately 35 percent immediately after 

mechanical treatments; to approximately 15 percent of the project area 20 years after treatment; to 10 

percent of the project area 30 years after treatment.

Alternative 3 experiences the most mortality and snag creation overtime of action alternatives. The effects 

of climate change, drought, and tree density are similar to those described in Alternative 2. The range of 

potential mortality occurring in thinned and unthinned portions of stands is similar to Alternative 2. However 

due to relatively more tree density than other action alternatives, more tree mortality (approximately 1 snag 

per acre more) occurs in Alternative 3. 

Direct Effects Large Trees, Species Composition, and Tree Removal

Design features for the fuels reduction alternative limit removals to trees less than 20 inches DBH. The 

direct effect of the fuels reduction alternative on tree removals is that approximately 44 percent of the trees 

0 to 10 inches DBH and 21 percent of the trees 10 to 20 inches in diameter are removed. Tree removals are 

constrained by both the 20 inch diameter limit and the 50 percent canopy cover objective. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-53

Tree removals are focused on reducing fire severity and the effects of wildfire. In as much as the alternative 

reduces fuel ladders near or under large trees (35 inches in diameter), the direct effect is to reduce the 

potential that these large trees will be killed during a wildfire or prescribed fire. This same effect occurs in 

other action alternatives. 

Mechanical treatments remove approximately 28,000 trees in the 10 to 20 inch diameter class and 456,000 in 

the 0 to 10 inch diameter class. This leaves approximately 108,000 trees and 584,000 trees in the 10 to 20

inch and 0 to 10 inch diameter classes respectively. Table 3-11-6 displays the tree removals by diameter 

class and the percentage remaining after mechanical treatment.

Table 3-11-6 Tree numbers for Alternative 3 across all project acres – treated and untreated acres

Alternative 3 -Fuels Reduction

DBH Class 0" to 10" 10" to 20" 20" to 30" 30" to 35" over 35"

Existing trees (1000s) 1040 136 53 13 18

Mechanical Treatment 

Tree Removals (1000s ) 456 28 0 0 0

Percent removal 44% 21% 0% 0% 0%

Percent remaining 56% 79% 100% 100% 100%

Indirect Effects large trees, species composition, and tree removal

Tree removals and subsequent effects on growth of remaining trees occur with the passage of time. The 

proportion of large tree (trees > 35 inches) stem area (basal area) or large tree occupancy is 40 percent of the 

totals stem area for the Bull Unit and 23 percent for the Providence Unit prior to treatment. 

After mechanical and initial prescribed fire treatments in the Bull Unit the fuels reduction alternative results 

in 46 percent of total tree stem area in large trees. In the Providence Unit all action alternatives create 

approximately the same amount of large tree stem area over time. Action alternatives in the Providence Unit 

take the existing 23 percent large stem area and increase it over the 30 years to approximately 43 percent. In 

the Providence Unit the No action alternative results 35 percent of the stem area in large trees. 

Alternative 3 has a limited to no effect on species composition for the 30 year analysis period. White fir and 

incense cedar dominance drops by 1 percent; while pine dominance increases by 1 percent.

Direct Effects Regeneration, Brush Openings, and Competing Vegetation

The fuels reduction alternative does not provide for conifer regeneration. As a result there are no direct 

effects on conifer regeneration or brush. The effects are similar to the No Action alternative.

Plantation maintenance direct effects are the same as Alternative 2 with the exception of 64 acres not 

receiving chemical treatment in Alternative 3. These 64 acres of plantations, shelterwoods and one brush 

field are found in the Providence Unit (plan_ids 250, 292, 299, and 1043). Sprouting brush species are found 

mixed with conifer saplings. The brush is taller than two feet and has deep rooting systems. The proposed 

hand and mechanical treatments will reduce the above ground size of plants, but not the underground root 

systems. The direct effect on these areas will be to reduce the brush cover only temporarily (less than 2 

years). 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-54

Indirect Effects Regeneration, Brush Openings, and Competing Vegetation

Indirect effects on conifer regeneration in existing openings are similar to the No Action alternative. Tree 

densities are maintained high to meet the 50 percent canopy objectives. Thus tree regeneration continues to 

favor shade loving (shade tolerant) white fir and incense-cedar. In this respect indirect effects in existing 

openings from the fuels reduction alternative are similar to the No Action. 

Plantation maintenance indirect effects are the same as Alternative 2 with the exception of 64 acres not

receiving chemical treatment in Alternative 3. In these 64 acres the above ground removal of ceanothus 

species, bear clover and sprouting manzanita will result in little to no release of soil moisture for increased 

growth. 

Direct Effects Prescribed Fire and Wildfire Severity

The fuels reduction alternative would have similar direct effects on vegetation from prescribed fire as 

Alternative 2.

Directly following mechanical treatments acres subject to high wildfire severity are reduced. The fuels 

reduction alternative direct effect is to increase approximately 325 fewer acres resilient to high fire severity 

compared to the No Action. The fuels reduction alternative increases acres resilient from approximately 320 

to 690 acres.

Indirect Effects Prescribed Fire and Wildfire Severity

The indirect effects from wildfire and prescribed fire resulting from the fuels reduction alternative are similar 

to those discussed in Alternative 2. 

Treatments under the fuels reduction alternative will have a similar effect on brush openings as Alternative 2. 

While no direct treatments will occur in existing openings, prescribed fire will tend to burn brush and reduce 

age and brush structure as described in Alternative 2. The treatment effects from prescribed fire described 

for Alternative 2 relating to brush openings apply here.

The fuels reduction alternative mechanical and prescribed fire treatments results in approximately 1,100 

more acres resilient to high fire severity as compared to the No Action Alternative after ten years in treated 

areas. The fuels reduction alternative maintains effectiveness of treatments over the analysis period as a 

result of prescribed fire maintenance. This maintenance effect is the same for all action alternatives.

Direct Effects Forest Restoration

Direct effects on ecological restoration are similar to those discussed under Alternative 2.

Restoration is the synergy between tree density, tree growth, fire severity, large trees, species composition 

and resilience to disturbance (fire and insects). Landscape heterogeneity is used as an indicator of ecological 

restoration. 

Alternative 3 and other action alternative reduces tree numbers over 11 inches DBH. Alternative 3 does not 

meet desired conditions for restoration. Alternative 3 is compared against the desired conditions for 

restoration for consistency. Alternatives that reduce tree numbers consistent with the desired conditions are 

closer to meeting restoration desired conditions. 16 of the 29 stands move closer to the desired condition 

under Alternative 3 (Figures 3-11-10). Alternative 3 tree removal achieves tree 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-55

Figure 3-11-10: Comparison of desired and post conditions treated for all stand employing Alternative 3 

(Fuels Reduction Option

numbers (> 11’ DBH) closer to the desired condition but removes fewer trees overall compared to other 

action alternatives. The direct effects on achieving restoration:

Alternative 3 reduces tree numbers per acre. 

Alternative 3 increases fire resilience 

Alternative 3 increases in insect and density resilience 

Alternative 3 results in more landscape heterogeneity following treatments (see Figure 3-11-17).

Two stands achieve the structural restoration targets for tree density and 16 moves closer. One 

stand falls below the desired condition.

As a result of the above indirect effects, Alternative 3 has a greater resistance to change and as a result 

greater resilience compared to the No Action. 

Indirect Effects Forest Restoration

Over the course of the restoration analysis period Alternative 3:

Increases the proportion of large trees from 40 percent to 68 percent of stem area in the Bull Unit 

and from 23 percent to 43 percent in the Providence Unit.

Increases the proportion of pine species from 21 percent to 22 percent (approximately the same for 

all action alternatives)

0

20

40

60

80

100

120

140

208235236250280281292295299301306316331346365380449450499796811838961962964965

104310561057

Trees per Acre > 11"

Stand Number

Fuels Reduction - Alternative 3 

Desired Condition vs Post Treatment

Trees per acre Remaining Trees per acre removed

Desired Condition Canyons Desired condition Ridges
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-56

Has increased resilience to severe fire from approximately 320 acres to 1,660 acres in treated area 

(Figure 3-11-15) 

Increases resistance of trees to density induced mortality and insect disturbance from 12 percent to 

30 percent of treated acres in the Providence Unit and from 21 percent to 40 percent in the Bull Unit 

(Figure 3-11-14).

Cumulative Effects 

Alternative 3 (Providence Unit), Dinky South, Dinkey North and private forest treatments treat a gross area of 

approximately 4,900 acres. These proposed projects are found adjacent to each other and result in 

approximately 550 acre reduction in tree canopy cover over 50 percent. This is a direct cumulative shift 

locally of approximately 25 percent of the area to more open tree canopy conditions. 

Across the (72,000 acres) cumulative effects boundary alternative 3 and current and reasonably foreseeable 

actions result in a direct cumulative reduction of approximately 1 percent in acres with tree canopy cover 

over 50 percent.

Alternative 3 (Providence Unit), Dinky South, and private forest treatments will reduce stand density and 

increase tree vigor over. The direct cumulative effect across the local scale (4,900 acres) is to increase the 

resistance to insect attack and density induced tree stress. However, the cumulative effect of the fuels 

reduction alternative approximately the same as other action alternatives. Prior to treatments there are 

approximately 2,100 acres at high risk to insect or density mortality; this is approximately 40 percent of the 

4,900 acre local scale effects area. Following treatments of proposed projects this results in approximately 

1,100 acres still subject to density induced mortality or approximately 20 percent of the 4,900 acre local scale 

cumulative effects area. 

The other cumulative effects for tree density are the same as Alternative 2. 

The indirect cumulative effects on tree species and large trees are similar to Alternative 2. That is that the 

fuels reduction alternative results in approximately a 3 percent increase in large trees over the No Action 

Alternative after 30 years of growth. This is cumulatively about the same as other action alternatives, 

present and reasonably foreseeable actions. 

Direct cumulative effects on severe wildfire are the same for actions alternatives. 

The cumulative effects on ecological restoration from the 2001 framework alternative are discussed under 

Alternative 2.

3-11.4.4 Alternative 4 – GTR (Ecological Restoration)

The main theme of Alternative 4 is ecological restoration consistent with frequent fire forest conditions using 

regeneration in groups and tree removal based upon retention of key wildlife habitat structures. 

Heterogeneity is promoted through variable residual tree density based upon topographic and aspect zones. 

Treatments are design to comply with the 2004 SNFPA. This alternative differs from Alternative 2 – unevenaged management, in that ecological restoration does not seek to return to past structures, rather ecological 

restoration seeks to mimic processes (fire) and conditions (soil moisture) that shape forest structure under 

frequent fire conditions.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-57

Direct and Indirect Effects

Direct Effects Tree Canopy Cover

Canyon, south/west, and neutral thinning strategies reduce tree canopy cover below 50 percent. Treatments 

in Alternative 4 results in a drop from approximately 1,145 acres to 485 acres over 50 percent canopy cover. 

Within modeled fisher rest sites Alternative 4 drops approximately 1/4 of the fisher rest sites drop below 50 

percent tree canopy cover. That is in forest structures important to fisher movement Alternative 4 reduces 

acres in dense tree canopy cover. Proposed treatments remove some understory trees and some trees along 

the edge of rest sites to achieve the desired conditions. 

Indirect Effects Tree Canopy Cover

Acres of canopy cover over 50 percent increases over the thirty-year analysis period following thinning in all 

action alternatives. After 30 years Alternative 3 produces approximately 920 acres with a canopy cover over 

50 percent. 

Should a wildfire enter the project area after the treatments are completed (approximately 10 to 15 years 

after present time) Alternative 4 would retain approximately 945 acres over 50 percent tree canopy cover.

Direct Effects Insect and Tree Density Mortality - Resilience

Immediately following mechanical tree removal treatment the ecological restoration alternative increases 

from 15 percent resilient or at low risk to insect or density induced mortality to approximately 45 percent of 

the project area (low risk is 35 percent of max SDI). 

Indirect Effects Insect and Tree Density Mortality - Resilience

As with other alternatives, growth increases stand density over time. Pretreatment approximately 15 

percent of project acres are resilient or at low risk to density induced mortality. Increases in stand density 

result in decreases in acres resilient to insect or density induced mortality. With growth, acres resilient (low 

risk) to insect or density induced mortality decreases from approximately 45 percent immediately after 

mechanical treatments; to approximately 25 percent of the project area 30 years after treatment; to 10 

percent of the project area 30 years after treatment.

The effects of climate change, drought, and tree density are similar to those described in Alternative 2. 

Alternative 4 removes between 0 and 19 percent of existing basal area. This thinning improves tree vigor and 

maintains stand structure consistent with restoration and resilience objectives. 

Direct Effects Large Trees, Species Composition, and Tree Removal

Design features for the Ecological Restoration alternative limit removals to trees less than 30 inches DBH. 

Tree removals in Alternative 4 are focused on retaining and improving shade intolerant pine and oak, 

increasing landscape heterogeneity (nuetral aspects, southwest aspects and canyon) and reducing fire 

severity. Tree removals for fuels reduction are focused on trees less than 20 inches DBH. Appendix G 

contains tree removals and by tree size class for each stand. The direct effect of the Ecological Restoration 

alternative on tree removals is that approximately 44 percent of the trees 0to 10 inches DBH and 25 percent 

of the trees 10to 20 inches in diameter are removed, and approximately 6 percent of trees 20 to 30 inches

DBH. Tree removals are focused on retaining and improving shade intolerant pine and oak, increasing 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-58

landscape heterogeneity and reducing fire severity. Ladder fuels within stands and trees found under larger 

pine or oaks are often 20 to 30 inches DBH fir or incense cedar. This alternative meets the intent of GTR-220 

by removing these fir and incense cedar that dominate the understory and result from a lack of frequent fire

on the landscape. In as much as the alternative reduces fuel ladders near or under large trees (35 inches

DBH), the direct effect is to reduce the potential that these large trees will be killed during a wildfire or 

prescribed fire. This same effect occurs in other action alternatives. 

Mechanical treatments remove approximately 3,000 trees in the 20 to 30 inch diameter class, 34,000 trees in 

the 10 to 20 inch diameter class and 458,000 in the 0 to 10 inch diameter class. This leaves approximately 

102,000 trees and 582,000 trees in the 10 to 20 inch and 0 to 10 inch diameter classes respectively. 

Removals also leave approximately 50,000 trees in the 20 to 30 inch diameter class. Table 3-11-7 displays the 

removals and retention of trees by size class.

Table 3-11-7 Tree numbers for Alternative 4 across all project acres – treated and untreated acres

Alternative 4 -Fuels Reduction

DBH Class 0" to 10" 10" to 20" 20" to 30" 30" to 35" over 35"

Existing trees (1000s) 1040 136 53 13 18

Mechanical Treatment 

Tree Removals (1000s ) 458 34 3 0 0

Percent removal 44% 25% 6% 0% 0%

Percent remaining 56% 75% 94% 100% 100%

Along with the other action alternatives, Alternative 4 has little direct effect on tree species composition.

Indirect Effects on Large Trees, Species Composition, and Tree Removal

Tree removals and subsequent effects on growth of remaining trees occur with the passage of time. The 

proportion of large tree (trees > 35 inches) stem area (basal area) or large tree occupancy is 40 percent of the 

total stem area for the Bull Unit and 23 percent for the Providence Unit prior to treatment. After mechanical 

and initial prescribed fire treatments in the Bull Unit the Ecological Restoration Alternative results in 51 

percent of total tree stem area in large trees. 

In the Providence Unit all action alternatives create approximately the same amount of large tree stem area 

over time. Action alternatives in the Providence Unit take the existing 23 percent large stem area and 

increase it over the 30 years to approximately 43 percent. In the Providence Unit the No Action Alternative 

results in 35 percent of the stem area in large trees after 30 years. 

Direct Effects on Conifer Regeneration and Brush Openings

The Ecological Restoration alternative provides the same treatments for existing openings, plantations, 

shelterwoods, and brush fields as Alternative 2. The direct effects discussed for these areas under 

Alternative 2 are the same for Alternative 4.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-59

Indirect Effects on Conifer Regeneration and Brush Openings

The Ecological Restoration alternative provides the same treatments for existing openings, plantations, and 

shelterwoods and brush fields as Alternative 2. The indirect effects discussed for these areas under 

Alternative 2 are the same for Alternative 4.

Direct Effects Prescribed Fire and Wildfire Severity

The Ecological Restoration Alternative would have similar direct effects on vegetation from prescribed fire as 

Alternative 2.

Directly following mechanical treatments acres subject to high wildfire severity are reduced. The Ecological 

Restoration Alternative direct effect is to increase approximately 390 fewer acres resilient to high fire 

severity compared to the No Action. The Ecological Restoration Alternative increases acres resilient from 

approximately 320 to 710 acres.

Indirect Effects prescribed fire and wildfire severity

The indirect effects from wildfire and prescribed fire resulting from the ecological restoration alternative are 

similar to those discussed in Alternative 2. 

Treatments under the Ecological Restoration Alternative would have a similar effect on brush openings as 

Alternative 2. While no direct treatments will occur in existing openings, prescribed fire will tend to burn 

brush and reduce age and brush structure as described in Alternative 2. The treatment effects from 

prescribed fire described for Alternative 2 relating to brush openings apply here.

The Ecological Restoration Alternative mechanical and prescribed fire treatments results in approximately 

1,100 more acres resilient to high fire severity as compared to the No Action Alternative after ten years. 

However, after 30 years the Ecological Restoration Alternative provides approximately 1,625 acres resilient to 

severe fire. 

The Ecological Restoration Alternative maintains effectiveness of treatments over the analysis period as a 

result of prescribed fire maintenance. This maintenance effect is the same for all action alternatives. 

Direct Effects on Forest Restoration

Restoration is the synergy between tree density, tree growth, fire severity, large trees, species composition 

and resilience to disturbance (fire and insects). Landscape heterogeneity is used as an indicator of ecological 

restoration. 

GTR-220 proposes three examples as criteria for the removal of trees 20 to 30 inches:

The first selection criteria is species

A second criterion would be tree growth form.

A third condition is middle to upper slope topographic position.

These criteria are not meant to be all inclusive, rather exemplify the situations managers should look at to 

meet restoration objectives. Alternative 4 addresses these example criteria by focusing on species 

composition, development of large trees, retention of key habitat structures, creating landscape 

heterogeneity
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-60

Trees 20 to 30 inches DBH are described as intermediate size trees in GTR-220 (North and others 2009). The 

removal of 20 to 30 inch DBH trees in Alternative 4 provides growing space for large trees (> 35 inches DBH). 

That is these trees allow larger trees to remain in the stand and somewhat smaller trees (30 to 35 inch DBH) 

to increase in size and become larger. In addition, where 20 to 30 inch DBH trees are shade intolerant or 

encroach upon the growing space for pine and oak 20 to 30 inch DBH removal creates conditions that 

enhance species composition consistent with restoration objectives. The removal of 20 to 30 inch DBH trees 

from both oaks and pine (regardless of size) provides conditions to maintain or enhance the growth of these 

species (see discussion under tree density). Alternative 4 retains fisher resting and denning structures. 

Twenty to 30 inch DBH trees often contribute to these fisher resting and denning structures. Alternative 4 

also retains tree decadence in trees larger than 20 inches DBH to provide for future resting structures. Trees 

0 to 20 inches DBH are removed to achieve fuels reduction and occasionally larger trees greater than 20

inches DBH contribute to ladder fuels and are removed. Canyon zones retain relatively high tree density, 

while southwest zones are relatively lower tree density. The removal of 20 to 30 inch DBH trees within 

southwest and neutral zones provides an opportunity to create the heterogeneity consistent with the 

restoration strategy outlined in GTR-220. 

In addition, GTR-220 indicates that the removal of trees in the 20 to 30 inch dbh class needs to be balanced 

against the desired development of more large trees and the future recruitment of large snags. The modeling 

indicates that large trees and snags are increased overtime. The proportional increase in large trees is 

particularly evident in the Bull Unit. Alternative 4 treatments (and other action alternatives) result in a short 

term (1 to 2 year) reduction in large snags, but over the 30 year analysis period produce more snags than the 

4 snags per acre in the standard and guidelines, but less than the other action alternatives. This is due to the 

lower stand density and greater tree vigor under Alternative 4. There is a tradeoff between more vigorous 

large trees that increase in size, and the creation of snags. However, there is no bottle neck in the number of 

large trees or snags. In comparison, the No Action Alternative creates the most snags and the fewest large 

trees over the analysis period. 

The combination of tree removals and retention in trees 20 to 30 inches DBH is consistent with the GTR-220 

restoration strategy.

Alternative 4 removes and retains trees based on topographic position and slope aspect. The distribution of 

topographic position and aspect under Alternative 4 results in a disruption of large continuous blocks of 

dense conifers. Alternative 4 reduces the size of vegetation patches with canopy cover over 50 percent 

canopy cover. A direct effect of Alternative 4 restoration design criteria is an increase the variability tree 

canopy cover and heterogeneous patches of vegetation across the project. 

Alternative 4 and other action alternative reduces tree numbers over 11 inches DBH. Alternative 4 desired 

conditions seek to mimic ecological processes that created the historical Sierra Nevada forests, but not 

strictly impose a structure. Alternative 4 is compared against the desired forest restoration desired 

conditions. Alternatives that reduce tree numbers consistent with the desired conditions are closer to 

meeting restoration desired conditions. Twenty of the 29 stands move closer to the desired condition under 

Alternative 4 (Figure 3-11-11). Alternative 4 tree removal achieves tree numbers (> 11 inches DBH) closer to 

the desired condition and removes more trees overall compared to other action alternatives. The direct 

effects on achieving restoration:

Alternative 4 reduces tree numbers per acre.

Alternative 4 increases fire resilience.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-61

Alternative 4 increases in insect and density resilience.

Alternative 4 results in more landscape heterogeneity following treatments (see Figure 3-11-17).

Six stands achieve the structural restoration targets for tree density and 20 moves closer.

Figure 3-11-11: Comparison of desired and post conditions treated for all stand employing Alternative 4 (GTR220 Option).

Indirect Effects Forest Restoration

An indirect effect of tree growth is the filling in of tree gaps created from thinning. Overtime this results in 

patches becoming more alike. Alternative 4 landscape heterogeneity lessens with time but stays above 

heterogeneity at the beginning of the analysis prior to treatment.

Over the course of the restoration analysis period Alternative 4:

Increases the proportion of large trees from 40 percent to 75 percent of stem area in the Bull Unit 

and from 23 percent to 28 percent in the Providence Unit.

Maintains the proportion of pine species at approximately 21 percent 

Has increase resilience to severe fire from approximately 710 acres (post treatment) to 1,625 (after 

30 years) acres in treated area (Figure 3-11-16) 

Increases resistance of trees to density induced mortality and insect disturbance from 12 percent to 

30 percent of treated acres in the Providence Unit and from 21 percent to 64 percent in the Bull Unit 

(Figure 3-11-14).

0

20

40

60

80

100

120

140

208235236250280281292295299301306316331346365380449450499796811838961962964965

104310561057

Trees per Acre > 11"

Stand Number

GTR 220- Alternative 4 Desired Condition vs Post Treatment

Trees per acre Remaining Trees per acre removed

Desired Condition Canyons Desired condition Ridges
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-62

Cumulative Effects 

Alternative 4 (Providence Unit), Dinky South, Dinkey North and private forest treatments treat a gross area of 

approximately 4,900 acres. These proposed projects are found adjacent to each other and result in 

approximately 700 acre reduction in tree canopy cover over 50 percent. This is a direct cumulative shift 

locally of approximately 35 percent of the area to more open tree canopy conditions. 

Across the (72,000 acres) cumulative effects boundary Alternative 4 and current and reasonably foreseeable 

actions result in a direct cumulative reduction of approximately 1 percent in acres with tree canopy cover 

over 50 percent.

Alternative 4 (Providence Unit), Dinky South, Dinkey North and private forest treatments will reduce stand 

density and increase tree vigor over. The direct cumulative effect across the local scale (4,900 acres) is to 

increase the resistance to insect attack and density induced tree stress. However, the cumulative affect of 

the Ecological Restoration alternative approximately the same as other action alternatives. Prior to 

treatments there are approximately 2,100 acres at high risk to insect or density mortality; this is 

approximately 40 percent of the 4,900 acre local scale effects area. Following treatments of proposed 

projects this results in approximately 20 percent of the 4,900 acre local scale cumulative effects area still 

subject to density induced mortality. 

The indirect cumulative effects on tree species and large trees are similar to Alternative 2. That is that the 

Ecological Restoration Alternative results in approximately a three percent increase in large trees over the No 

Action Alternative after 30 years of growth. This is cumulatively about the same as other action alternatives, 

present and reasonably foreseeable actions. 

Direct cumulative effects on severe wildfire are the same for actions alternatives. 

The cumulative effects on ecological restoration from the Ecological Restoration alternative are the same as 

discussed under Alternative 2.

The other cumulative effects are the same as Alternative 2. 

3-11.4.5 Alternative 5 – Proposed Action 

The main theme of this alternative is providing the level of vegetation disturbance desired by research inside 

the research area. Outside of research areas ecological restoration is treated identically to Alternative 4 and 

inside research watersheds treatments are identical to Alternative 2. 

Direct and Indirect Effects

Direct Effects Tree Canopy Cover

Canyon, south/west, and neutral thinning strategies (Alternative 4) combined with general forest and old 

forest thinning strategies (Alternative 2) reduce tree canopy cover below 50 percent. Treatments in 

Alternative 5 results in a drop from approximately 1,145 acres to 480 acres over 50 percent canopy cover. 

Within modeled fisher rest sites Alternative 5 drops approximately 2/3 of the fisher rest sites drop below 50 

percent tree canopy cover. That is in forest structures important to fisher movement Alternative 5 reduces 

acres in dense tree canopy cover. Proposed treatments remove some understory trees and some trees along 

the edge, and some middle story trees from rest sites to achieve the desired conditions. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-63

Indirect Effects Tree Canopy Cover

Acres of canopy cover over 50 percent increases over the 30 year analysis period following thinning in all 

action alternatives. After 30 years Alternative 5 produces approximately 975 acres with a canopy cover over 

50 percent. 

Should a wildfire enter the project area after the Proposed Action treatments are completed (approximately 

10 to 15 years after present time) Alternative 5 would retain approximately 965 acres over 50 percent tree 

canopy cover.

Direct Effects Insect and Tree Density Mortality - Resilience

Immediately following mechanical tree removal treatment the Proposed Action alternative increases from 15 

percent resilient to insect or density induced mortality to approximately 35 percent of the project area (low 

risk is 35 percent of max SDI). 

Indirect Effects Insect and Tree Density Mortality - Resilience 

As with other alternatives, growth increases stand density over time. Pretreatment approximately 15 

percent of project acres are resilient or at low risk to density induced mortality. Increases in stand density 

result in decreases in acres resilient to insect or density induced mortality. With growth, acres resilient (low 

risk) to insect or density induced mortality decreases from approximately 35 percent immediately after 

mechanical treatments; to approximately 20 percent of the project area 20 years after treatment; to 10 

percent of the project area 30 years after treatment.

Direct Effects Large Trees, Species Composition, and Tree Removal

Design features for the Proposed Action limit removals to trees less than 30 inches. The direct effect of the 

Proposed Action alternative on tree removals is that approximately 39 percent of the trees 0 to 10 inches 

DBH and 21 percent of the trees 10 to 20 inches DBH are removed. The Proposed Action removes 4 percent 

of trees 20 to 30 inches DBH.

In as much as the alternative reduces fuel ladders near or under large trees (35 inches in diameter), the direct 

effect is to reduce the potential that these large trees will be killed during a wildfire or prescribed fire. This 

same effect occurs in other action alternatives. 

Mechanical treatments remove approximately 28,000 trees in the 10 to 20 inch diameter class and 405,000 in 

the 0 to 10 inch diameter class. Removals in the 20 to 30 inch DBH class remove 2,000. This leaves 

approximately 51,000, 108,000 trees, 635,000 trees in the 20 to 30 inch, 10 to 20 inch and 0 to 10 inch

diameter classes respectively. Table 3-11-8 displays the removals and retention of trees by size class. 

Table 3-11-8 Tree numbers for Proposed Action across all project acres – treated and untreated acres

Alternative 5 -Proposed Action

DBH Class 0" to 10" 10" to 20" 20" to 30" 30" to 35" over 35"

Existing trees (1000s) 1040 136 53 13 18

Mechanical Treatment 

Tree Removals (1000s ) 635 108 51 13 18

Percent removal 39% 21% 4% 0% 0%

Percent remaining 61% 79% 96% 100% 100%
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-64

Indirect Effects Large Trees, Species Composition, and Tree Removal

Tree removals and subsequent effects on growth of remaining trees occur with the passage of time. The 

proportion of large tree (trees > 35 inches DBH) stem area (basal area) or large tree occupancy is 40 percent

of the total stem area for the Bull Unit and 23 percent for the Providence Unit prior to treatment. 

After mechanical and initial prescribed fire treatments in the Bull Unit the Proposed Action results in 46

percent of total tree stem area in large trees. In the Providence Unit all action alternatives create 

approximately the same amount of large tree stem area over time. Action alternatives in the Providence Unit 

take the existing 23 percent large stem area and increase it over the 30 years to approximately 43 percent. In 

the Providence Unit the No action Alternative results 35 percent of the stem area in large trees. 

Alternative 5 has a limited to no effect on species composition for the 30 year analysis period. White fir and 

incense-cedar dominance drops by 1 percent; while pine dominance increases by 1 percent.

Direct Effects regeneration, brush openings, and competing vegetation

The Proposed Action provides the same treatments for existing openings, plantations, and shelterwoods and 

brush fields as Alternative 2. The indirect effects discussed for these areas under Alternative 2 are the same 

for Alternative 5. 

Indirect Effects regeneration, brush openings, and competing vegetation

The Proposed Action would have similar effect on vegetation from treatments in plantations and existing 

openings as Alternative 2. Competing vegetation will also be treated the same. Both the Proposed Action and 

Alternative 2 propose treatment of existing openings and plantations on the same number of acres. The 

proposed treatments in plantations, openings and brush are the same.

Direct Effects prescribed fire and wildfire severity

The Proposed Action would have similar direct effects on vegetation from prescribed fire as Alternative 2. 

Both alternatives propose the use of prescribed fire on the same acres. Post harvest fuels treatments are 

also the same (tractor piling, hand piling). Prescribed fire treatments will be conducted under the same 

weather limitations. As a result of these similarities there will be little difference resulting from the 

application of prescribed fire.

Directly following mechanical treatments acres subject to high wildfire severity are reduced. The Proposed 

Action alternative direct effect is to increase acres resilient to fire. Approximately 310 more acres resilient to 

high fire severity compared to the No Action. The Proposed Action alternative increases acres resilient to 

wildfire from approximately 320 (before treatment) to 740 (after treatment) acres.

Indirect Effects prescribed fire and wildfire severity

The indirect effects from wildfire and prescribed fire resulting from the Proposed Action alternative are 

similar to those discussed in Alternative 2. Both alternatives propose the use of prescribed fire on the same 

acres. Post harvest fuels treatments are also the same (tractor piling, hand piling). Prescribed fire treatments 

will be conducted under the same weather limitations. As a result of these similarities there will be little 

difference resulting from the application of prescribed fire.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-65

Treatments under the Proposed Action Alternative will have a similar effect on brush openings as Alternative 

2. While no direct treatments will occur in existing openings, prescribed fire will tend to burn brush and 

reduce age and brush structure as described in Alternative 2. The treatment effects from prescribed fire 

described for Alternative 2 relating to brush openings apply here.

The Proposed Action alternative mechanical and prescribed fire treatments results in approximately 1,200 

more acres resilient to high fire severity as compared to the No Action Alternative after ten years in treated 

areas. The Proposed Action alternative maintains effectiveness of treatments over the analysis period as a 

result of prescribed fire maintenance. This maintenance effect is the same for all action alternatives.

Direct Effects Forest Restoration

Direct effects on ecological restoration are similar to those discussed under Alternative 2 and 4. Both the 

proposed action and Alternative 2 implement identical restoration strategies in the research areas. As a 

result these areas will result in the same effects on restoration. Outside of research areas the Proposed 

Action implements treatments identical to Alternative 4. As a result the Proposed Action will have the same 

effects in areas outside of research areas as Alternative 4.

Restoration is the synergy between tree density, tree growth, fire severity, large trees, species composition 

and resilience to disturbance (fire and insects). Landscape heterogeneity is used as an indicator of ecological 

restoration. 

Alternative 5 increases the landscape heterogeneity after treatments.

Alternative 5 and other action alternatives reduce tree numbers over 11 inches DBH. Alternative 5 desired 

conditions are a hybrid of those found in Alternative 2 and 4. Alternative 5 is compared against the desired 

conditions for restoration for consistency. Alternatives that reduce tree numbers consistent with the desired 

conditions are closer to meeting restoration desired conditions. Eighteen of the 29 stands move closer to the 

desired condition under Alternative 5 (Figure 3-11-12). The direct effects on achieving restoration are:

Alternative 5 reduces tree numbers per acre. 

Alternative 5 increases fire resilience 

Alternative 5 increases in insect and density resilience 

Alternative 5 results in more landscape heterogeneity following treatments (see Figure 3-11-17).

Six stands achieve the structural restoration targets for tree density and 18 move closer. One stand 

falls below the desired condition.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-66

Figure 3-11-12: Comparison of desired and post conditions treated for all stand employing Alternative 5 

(Proposed Action).

Indirect Effects Forest Restoration

An indirect effect of tree growth is the filling in of tree gaps created from thinning. Overtime this results in 

patches becoming more alike. Alternative 5 landscape heterogeneity lessens with time and falls back to the 

heterogeneity at the beginning of the analysis.

Over the course of the restoration analysis period Alternative 5:

Increases the proportion of large trees from 40 percent to 49 percent of stem area in the Bull Unit 

and from 23 percent to 28 percent in the providence area.

Maintains the proportion of pine species at approximately 21 percent 

Has increased resilience to severe fire from approximately 632 acres (post treatment) to 1,620 (after 

30 years) acres in treated area (Figure 3-11-16) 

Increases resistance of trees to density induced mortality and insect disturbance from 12 percent to 

30 percent of treated acres in the Providence Unit and from 21 percent to 43 percent in the Bull Unit 

(Figure 3-11-14).

Cumulative Effects 

The Alternative 5 (Providence Unit), Dinky South, Dinkey North and private forest treatments treat a gross 

area of approximately 4,900 acres. These proposed projects are found adjacent to each other and result in 

approximately 550 acre reduction in tree canopy cover over 50 percent. This is a direct cumulative shift

0

20

40

60

80

100

120

140

208235236250280281292295299301306316331346365380449450499796811838961962964965

104310561057

Trees per Acre > 11"

Stand Number

Proposed Action - Alternative 5

Desired Condition vs Post Treatment

Trees per acre Remaining Trees per acre removed

Desired Condition Canyons Desired condition Ridges
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-67

locally of approximately 30 percent of the area to more open tree canopy conditions. This is approximate the 

same as other action alternatives

Across the (72,000 acres) cumulative effects boundary Alternative 5 and current and reasonably foreseeable 

actions result in a direct cumulative reduction of approximately 1 percent in acres with tree canopy cover 

over 50 percent.

The Alternative 5 (Providence Unit), Dinky South, and private forest treatments would reduce stand density 

and increase tree vigor over. The direct cumulative effect across the local scale (4,900 acres) is to increase 

the resistance to insect attack and density induced tree stress. However, computer modeling indicates that 

the cumulative effect of the Hybrid alternative is approximately the same as other action alternatives. Prior 

to treatments there are approximately 2,100 acres at high risk to insect or density mortality; this is 

approximately 42 percent of the 4,900 acre local scale effects area. Following treatments of proposed 

projects this results in approximately 20 percent of the 4,900 acre local scale cumulative effects area still 

subject to density induced mortality. 

The other cumulative effects for tree density are the same as Alternative 2 and 4. The Proposed Action is a 

combination of alternative 2 and 4. 

The indirect cumulative effects on tree species and large trees are similar to Alternative 2 and 4. That is that 

the Hybrid alternative results in approximately a three percent increase in large trees over the No Action 

Alternative after 30 years of growth. This is cumulatively about the same as other action alternatives, 

present and reasonably foreseeable actions. 

Direct cumulative effects on severe wildfire are the same for actions alternatives. 

3-11.5 Comparison of Alternatives

3-11.5.1 Tree Canopy Cover

Treatments in Alternative 2 results in a drop from approximately 1,145 acres to 580 acres over 50 percent 

canopy cover in treated areas (Figure 3-11-13). This is approximately 290 acre reduction from the Bull and 

290 acres from the Providence Unit. Alternative 2 ranks second at maintaining the most acres above 50 

percent canopy cover. This is compared to 680 acres maintained above 50 percent canopy cover resulting 

after Alternative 3 (fuels reduction) treatments.

Acres of canopy cover over 50 percent increases over the 30 year analysis period following thinning in all 

action alternatives. After 30 years Alternative 2 produces approximately 990 acres with a canopy cover over 

50 percent. This is approximately equal to what is produced under Alternative 3 (fuels reduction) and 

approximately 20 acres more than Alternative 5 (proposed action). Alternative 2 produces the least acres of 

tree canopy over 50 percent after 30 years. 

Figure 3-11-13: Comparison of acres with tree canopy cover greater than 50 percent for post treatment and 

after wildlife for all alternatives.
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-68

Alternative 3 (fuels reduction) design criteria maintain the most acres above 50 percent canopy cover of 

action alternatives (Rank 1). The fuels reduction alternative maintains approximately 200 acres more over 50 

percent canopy cover following treatment more than Alternative 4 and 5 (the alternatives with the lowest 

acres over 50 percent following treatment). The fuels reduction alternative maintains approximately 490 

acres less than the No Action over 50 percent canopy cover following treatment. 

While Alternative 3 maintains the most acres above 50 percent canopy cover generally, Alternative 3 

maintains the least acres of modeled fisher rest sites above 50 percent canopy cover. Alternative 3 does not 

include treatments that limit removals in fisher rest sites.

3-11.5.2 Insect and Tree Density - Resilience

The direct effects of Alternative 2 would be to reduce the number of acres above the high density mortality 

threshold. The action alternatives do not eliminate the potential for insect attack or disease. Under 

Alternative 2 approximately 30 percent of treated areas have low index and mortality risk (resilience). 

Alternative 3 and Alternative 5 also maintain approximately the same percent of treated areas resilient to 

insect and density mortality. Alternative 2 maintains the highest insect and density resilience in the 

Providence Unit and the lowest within the Bull Unit.

Immediately following treatment Alternative 3 increases from 15 percent resilient to insect or density 

induced mortality to approximately 35 percent of the project area (low risk is 35 percent of max SDI). This 

approximately the same amount of the treated area resilient to insect and density induce mortality as 

Alternative 2 and 5. This is more than the 15 percent of the project area resilient to insect or density induced 

mortality in the No Action Alternative.

Resilience lessens with time after treatment. However, Alternative 2 maintains more acres at low risk to 

insect and density induced mortality (resilient) than the No Action Alternative throughout the 30 year 

analysis period. Ten years after treatments Alternative 2 has approximately 25 percent of treated acres at 

low risk of density induced and insect mortality; Alternative 4 (GTR) has the highest resilience with 

approximately 45 percent of the project acres at low risk of insect and density induced mortality. The other 

0

200

400

600

800

1000

1200

1400

Post Treatment After wildfire

Acres

Tree Canopy Cover Over 50% 

no Action uneven-aged fuels reduction ecological restoration proposed action
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-69

action alternatives (Alternative 3 and Alternative 5) each have approximately 35 percent of treated acres at 

low risk to insect and density induced mortality.

With Alternative 3, acres resilient (low risk) to insect or density induced mortality decreases from 

approximately 35 percent immediately after mechanical treatments; to approximately 15 percent of the 

project area 30 years after treatment; to 10 percent of the project area 30 years after treatment (Figure 3-11-

14). In comparison Alternative 4 decreases from 45 percent resilient (low risk) to insect or density induced 

mortality after mechanical treatments to approximately 25 percent in 20 years and 10 percent in 30 years. 

With the No Action less than 5 percent of the project area is at low risk to insect or density induced mortality 

after 30 years.

Figure 3-11-14 Insect and tree density resilience over the analysis period.

This analysis uses SDI as an index or indicator of density induced mortality and insect mortality. Stands at 

higher percentage of SDI are at greater risk of both insect attack and density induced mortality. These 

episodic waves of mortality are often triggered by drought or snow damage. The Proposed Action and other 

action alternatives will continue to experience mortality, but at lower levels. The amount of mortality is 

associated with residual tree density. Oliver in his 1997 research indicates that tree mortality in thinned 

Sierra Nevada stands ranged from 7 percent for open grown trees to 30 percent in thinned stands left in 

dense condition. In another study Oliver (2005) found that within thinned stands mortality increased after 10 

to 20 years. Areas thinned under action alternatives will experience similar mortality.

While proposed treatments in action alternatives including Alternative 5 remove trees and reduce tree 

density and improve tree vigor, the No Action Alternative allows stands to increase in tree density waiting for 

a drought cycle and eventual mortality at rates far higher than forests with fire regimes and forest structures 

that are consistent with the forest restoration purpose and need. Droughts will come and tree density will 

increase. Increasing stress from tree density, pollution and climate change will result in increased tree 

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

2010 2012 2022 2032 2042

Proportion of Project

Insect and Tree Density Resilience

No Action Uneven-aged Fuels Reduction Ecological Restoration Proposed Action
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-70

mortality in untreated areas. Tree mortality of 15 to 50 percent basal experienced in the past in similar or 

neighboring forests may actually be low estimates of future mortality with climate change. 

In contrast proposed treatments under action alternatives remove from 0 to 34 percent of stand basal area. 

Alternative 5 removes between 0 and 23 percent of existing basal area. This thinning improves tree vigor and 

maintains stand structure consistent with restoration and resilience objectives.

However, the simple metric of basal area change does not capture the fundamental differences in tree 

physiology that occur between vigorous trees growing in less dense forests (like action alternatives) and 

those grown under increasing tree density (like the no action) and subject to drought and pollution. Grulke 

and others (2009) summarized this fundamental loss in tree vigor and eventual forest decline in similar forest 

found in Southern California: high ambient ozone (O3) concentration and elevated nitrogen (N) deposition 

weakens and predisposes trees to bark beetle attacks, increases foliar senescence and fuel build-up, and 

increases water stress during drought periods.

3-11.5.3 Large Trees, tree removals and species composition

Table 3-11-7 displays the number of trees removed by diameter class for each of the action alternatives. 

Alternative 5 removes approximately 39 percent of trees 0 to 10 inches, 21 percent of trees 10 to 20 inches 

DBH, and 4 percent of trees 20 to 30 inches DBH from mechanically treated areas. Alternative 4 removes 

approximately 44 percent of trees 0 to 10 inches, 25 percent of trees 10 to 20 inches DBH, and 6 percent of 

trees 20 to 30 inches DBH from mechanically treated areas.

Table 3-11-7 Tree numbers for each alternative across all project acres – treated and untreated acres

Alternative/DBH 0" to 10" 10" to 20" 20" to 30" 30" to 35" over 35"

Mechanical 

Treatment 

Tree 

Removals 

Values in 

1000s trees

No Action 0 0 0 0 0

Structural 

Restoration 347 27 4 0 0

Fuels Reduction 456 28 0 0 0

Ecological 

Restoration 458 34 3 0 0

Proposed Action 405 28 2 0 0

Alternative 0" to 10" 10" to 20" 20" to 30" 30" to 35" over 35"

Trees 

Remaining 

After 

Mechanical 

Treatment

Values in 

1000s trees

No Action 1040 136 53 13 18

Structural 

Restoration 693 109 49 13 18

Fuels Reduction 584 108 53 13 18

Ecological 

Restoration 582 102 50 13 18

Proposed Action 635 108 51 13 18
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-71

Alternative 2 and other action alternatives keep tree densities lower in treated diameter classes over the 30

0%

10%

20%

30%

40%

50%

60%

70%

80%

2010 2012 2022 2032 2042

Percent of Basal Area Occupied by 

Trees of Over 35" DBH Over Time 

for the KREW Bull Area

No Action uneven-aged

fuels reduction ecological restoration

proposed action

0%

5%

10%

15%

20%

25%

30%

35%

40%

45%

50%

2010 2012 2022 2032 2042

Percent of Basal Area Occupied by 

Trees of Over 35" DBH Over Time 

for the KREW Providence Area

No Action uneven-aged

fuels reduction ecological restoration

proposed action

Figure 3-11-15: Comparison of percent basal area of trees with over 35” DBH for a 30 year period 

in the Providence and Bull management Units for all proposed alternatives
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-72

year analysis period than the No Action alternative. The greatest difference in tree numbers between 

alternatives occurs in the smaller diameter classes (0 to 10 inches DBH). Alternative 2 maintains the most 

small trees of action alternatives; Alternative 2 retains approximately 109,000 more trees in the 0 to 10” class 

than Alternative 3 (fuels reduction). Alternative 2 removes approximately 33 percent of the 0 to 10” class. 

The difference reflects the different goals of each action alternative. 

Alternative 2 removes approximately the same number of 10” to 20” diameter trees as Alternative 3 and 

Alternative 5. Alternative 2 removes the most 20” to 30” trees (approximately 4,000 trees) or approximately 

2 per treated acre.

The action alternatives maintain more acres with large trees in the face of severe wildfire than the No Action 

alternative (Figure 3-11-15). Alternative 2 has fewer acres subject to severe wildfire over the 30 year analysis 

period compared the No Action, but more than any of the other action alternatives including the Proposed 

Action. The ecological restoration alternative maintains more large trees than the No Action due to fewer 

acres subject to severe fire.

The indirect effect of Alternative 2 is to increase the proportion of shade intolerant species by: favoring pine 

and black oak over fir and incense-cedar, and by planting pine in openings. These two treatments (favoring 

pine and black oak over fir and incense-cedar and by planting pine in openings) result in a small increase (2 

percent) in pine stem area after 30 years compared to the No Action. White fir declines in dominance during 

the analysis period with Alternative 2. Both the No Action and Alternative 3 see increases in white fir 

dominance over the analysis period. Within the analysis time frame the lack of conditions suitable for pine 

regeneration limits increased proportion of pine species measured in basal area for all action alternatives. 

After mechanical and initial prescribed fire treatments in the Bull Unit the Ecological Restoration Alternative 

(Alternative 3) results in 51 percent of total tree stem area in large trees. This is more than the 40 percent 

proportion of large trees under the No Action Alternative and more than the approximately 45 percent under 

Alternatives 2 and 3 (Bull area). After 30 years the proportions of large trees under the Ecological 

Restoration alternative increases to approximately 75 percent of the total tree stem area for the Bull area. 

This is compared to 60 percent of large tree occupancy under the No Action and approximately 68 percent 

occupancy under Alternative 2 and 3. 

After mechanical and initial prescribed fire treatments in the Bull Unit the fuels reduction Alternative 3 

results in 46 percent of total tree stem area in large trees. This is more than the 40 percent proportion of 

large trees under the No Action Alternative and less than the approximately 50 percent under Alternatives 4 

and 5 (Bull area). After 30 years the proportion of large trees under the fuels reduction alternative increases 

to approximately 68 percent of the total tree stem area for the Bull area. This is compared to 60 percent of 

large tree occupancy under the No Action and approximately 75 percent occupancy under Alternatives 4 and 

5. 

In the Providence Unit all action alternatives create approximately the same amount of large tree stem area 

over time. Action alternatives in the Providence Unit take the existing 23 percent large stem area and 

increase it over the 30 years to approximately 43 percent. In the Providence Unit the No Action Alternative 

results in 35 percent of the stem area in large trees. 
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-73

Figure 3-11-16: Effects of Fires severity on tree mortality post mechanical treatments for all 

alternatives

3-11.5.4 Wildfire severity

The Proposed Action has the most acres subject to high fire severity among action alternatives (Figure 3-11-

16). Alternative 2 produces the least treated acres resilient to high severity fire of the action alternatives; 

Alternative 2 results in approximately 84 acres less resilient to high severity wildfire compared to Alternative 

4 (most resilient to high severity fire) and approximately 300 acre more resilient to high severity wildfire 

compared to the No Action Alternative. Alternative 2 ranks fourth among action alternatives for resilience to 

severe fire. Alternative 2 achieves the lowest ranking among action alternatives due to the uneven-aged 

treatment. Uneven-aged treatment maintains more trees in smaller diameter classes than do other action 

alternatives. This tree layering or maintenance of understory tree structure promotes more crown torching 

than other action alternatives.

Directly following mechanical treatments acres subject to high wildfire severity are reduced. The fuels 

reduction alternative results in approximately 325 fewer acres resilient to high fire severity compared to the 

No Action. However, there are fewer acres (approximately 60 acres) resilient to high severity fire as 

compared to Alternative 4 having the fewest acres subject to high severity fire. The Ecological Restoration 

Alternative has the fewest acres subject to high severity wildfire (rank 1). The fuels reduction alternative and 

proposed action ranks 2nd among action alternatives in reduce high severity fire and increasing fire 

resilience. 

0

200

400

600

800

1000

1200

1400

Low (<25% mortality) Moderate High (>75% mortality)

Acres

Fire Severity After Mechanical Treatment

No Action Uneven-aged Fuels Reduction Ecological Restoration Proposed Action
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-74

3-11.5.5 Forest Restoration

Restoration is the synergy between tree density, tree growth, fire severity, large trees, species composition 

and resilience to disturbance (fire and insects). Landscape heterogeneity, large trees, pine dominance, 

resilience are used as an indicator of ecological restoration. 

Alternative 5 more closely achieves desired tree numbers per acre compared to the No Action 

Alternative. However, Alternative 5 creates approximately the same proportion of large trees as 

alternatives 2 and 5 (68 percent) in the Bull area. Alternative 2 creates lower proportion of large 

trees compared to Alternative 4 in the Bull Unit.

Alternative 5 achieves approximately the same increases in fire resilience as Alternatives 2 and 3, but 

less than Alternative 4.

Alternative 5 achieves approximately the same increases in insect and density resilience as 

alternatives 2 and 3, but less than Alternative 4.

Alternative 5 results in approximately the same landscape heterogeneity as Alternative 3.

Alternative 2 results in lower landscape heterogeneity than other action alternatives and the No 

Action Alternative (see Figure 3-11-17). Alternative 4 (ecological restoration) results in the greatest 

landscape heterogeneity after treatment and over the 30 year analysis period of any alternative. 

Higher landscape heterogeneity more closely approximates the desired condition for ecological 

restoration.

Alternative 5, 3 and 4 see either no increases in pine or increases in fir and incense cedar. Alternative 

2 results in a trend toward higher pine dominance. The No Action sees declines in pine dominance 

and increases in fir and incense cedar.

Alternative 2 (structural restoration) sees the most stands move into the desired trees per acre range 

and the most stands (18) move closer to structural restoration tree numbers.

As a result of the above direct effects, Alternative 4 has a greater resistance to change and as a result 

greater resilience compared to the No Action and other action alternatives. However, Alternative 2 

ranks approximately equal in resilience to Alternatives 3 and 5. Alternative 2 ranks below Alternative 

4.

Alternative 5 has the same proportion of large trees as Alternative 2 and 3 over the analysis period in 

the Bull Unit (Figure 3-11-15). Has approximately 5 percent less than Alternative 4 at the end of the 

30 year analysis period.

Alternative 5 has approximately the same resilience to severe fire as Alternatives 2 and 5 (Figure 3-

11-16) 

After treatment Alternative 5 has the least acres resistant to insect and density induced mortality 

compared to other action alternatives. Alternative 2 increases resistance of trees to insect 

disturbance after treatments compared to other action alternatives. However, alternative 4 

maintains more resistance to insect and density induce mortality over the analysis period resulting in 

greater resilience (Figure 3-11-14).
Final Environmental Impact Statement Kings River Experimental Watershed Project

Chapter 3-11 – Vegetation and Silviculture 3.11-75

Figure 3-11-15: Change of heterogeneity based on the coefficient of variation for canopy cover. Alternative 

4 creates the most heterogeneity across the project area. Over time as patches of trees grow heterogeneity 

lessens. The No Action Alternative results in dramatic reductions in heterogeneity over time.

0.00

0.05

0.10

0.15

0.20

0.25

0.30

0.35

0.40

0.45

2010 2012 2022 2032 2042

Canopy Cover Coefficeint of Variation

Ecological Restoration - Heterogeneity through Time

No Action Uneven-aged fuels reduction

ecological restoration Proposed Action