Chiiloquin ranger district




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Current Conditions

Grazing, timber harvest, and fire exclusion have altered forest structure, vegetation mosaics, fuel

loadings, and seasonal fuel moisture conditions during the last one hundred years in the ponderosa pine

and mixed conifer forest communities. Management activities (very limited in this community) have had

little influence in the subalpine lodgepole-white fir community. These changes have produced new fire

regimes in the ponderosa pine and mixed conifer communities that are very different from those exhibited

in the reference era.

SOS Watershed Assessment 28


The fire regimes in ponderosa pine and mixed conifer can now be classed as one regime exhibiting

infrequent, high intensity/severity fire. Stand replacement fire during the past 15 years has increased such

that 10% of the watershed burns per decade It is anticipated that this rate will increase as fuels continue

accumulating and shrub and tree stocking increase. Current stands are at high and immediate risk as

indicated by the Lone Pine, Cave Mountain and Cowboy fires, and the extensive stress related insect and

disease mortality the last few years. Insect and disease agents have the ability to cause nearly 100%

mortality. There is a high risk to residual stands if large amounts of dead material is not removed. Large

numbers of dead/dying trees become a risk by:

Increasing fire hazard.

Mechanical damage or wounding to residual or regenerated stand when they fall.

Short-term colonization sites increase insect numbers which then emerge to attack live trees.

The stand replacement rate exhibited in the South of Sprague watershed is significantly lower than the

Chiloquin Ranger District average. This is likely due to the stochastic nature of fire occurrence and

variance obtained when analyzing relatively small blocks such as this 83,000 acre watershed. If one uses

the district averages for characterizing the current fire regime the significance of the recent changes and

their critical nature becomes clearer. Stand replacement fire frequency has increased from every 220

years during the 1970's, to every 75 years in the 1980's, to every 17 years during the 1990's. While it is

certain that some of this increase can be attributed to unusually dry climatic conditions, most of it derives

from unnatural accumulations of dead and live fuel.

B. What is the frequency of conditions that lead to stand replacement events?

Those aspects of forest structure, health, and seasonal water allocation that predispose it to insect and

disease outbreaks (beyond endemic levels) also contribute to high intensity/severity wildfire.

Conditions that lead to widespread mortality in forest overstories due to insect and disease are generally

associated with overstocked stands. Stocking of trees and shrubs tends to increase with time until light

limitations prevent additional recruitment. As stocking passes threshold levels, each new stem provides a

degree of competition for ecosystem resources (at the expense of it's neighbors). As greater portions of

the forest ecosystem nutrient pool become organically bound, and as more woody stems per unit land

mass become established, water and nutrient deficiencies occur. During water-poor years large

percentages of the overstory become susceptible to a wide variety of insect and disease agents. Partial

mortality of trees and shrubs as well as complete mortality temporarily reduces competition but increases

standing and down forest fuel loads. New recruitment of shrubs and trees feeds the cycle until,

ultimately, fire combusts the fuel, mineralizing the organically-bound nutrients, making them available for

plant uptake again..

Trees native to this area did not develop a survival strategy for growing under high stocking conditions.

Most pine survival strategies were based on low stocking levels. The tree's natural defenses; thick bark

to protect against fire, abundant sap to "pitch out" beetles etc., are ineffective in highly stocked stands.

A continuous understory of seasonally flammable live fuel provides the competition that reduces

resistance to insect and disease as well as a fuel strata that elevates surface fires to overstory crowns.

Shade tolerant trees and shrubs become established in the understory over time when fire is excluded.

SOS Watershed Assessment 29


During the early part of the fire season (which generally is in effect from May through October) the

understory shrub and tree component is relatively fire resistant (high live fuel moisture values). Later in

the season (usually August through the season-ending rain event that occurs generally after September

15) the shrubs become very flammable and provide a "ladder of fuel" for surface fires to climb into the

crowns. In addition to the ladder provided by the seasonal lows of live fuel moisture, needle and twig

fall is caught by the shrub component. The fine dead fuel suspended in the air provides a highly

flammable fuel that contributes to carrying fire to the crowns, even in early season fires when the shrubs

have high live fuel moisture.

C. What actions or events would lead to reduced risk of stand replacement events?

Reducing the stocking leveL of trees and shrubs, as well as reducing surface litter loads would decrease

the stand replacement event return interval. Several methods might be employed to accomplish these

items. Reestablishment of frequent, low intensity/severity fire would return the area to a fire regime that

included very little stand replacement wildfire or insect and disease outbreaks. Reshaping the forest stand

structure and fuel loadings to reach that type of fire regime while maintaining a living overstory will be

difficult. It may require multiple entries of fire and/or combinations of harvest and fire, mechanical

manipulation (whip felling, precommercial thinning, crushing, etc.) and fire.

SOS Watershed Assessment 30


4. What are the relationships between management activities and TES habitat?

How has habitat been altered by management activities?


A. What was the role of reference era disturbance regimes in the creation of key habitat areas?

Riparian

Fire reduced conifer encroachment and facilitated riparian hardwood and grass species rejuvenation.

Historic documents refer to large amounts of aspen, cottonwood, and some willow, in the Sprague River

valley. These same references reported less willow in the upland riparian areas, mostly limited to channel

areas. Sagebrush was also present in some riparian edge areas.

Mountain mahogany

References indicate there were large areas of Mountain mahogany in SOS during the reference period.

Fire probably limited conifer encroachment into Mountain mahogany habitat (rocky soils, etc...). In the

open grassy stands (common in the reference period), more gophers were probably present, and their

feeding habits would have limited successful conifer regeneration. Mahogany regeneration may have

been stimulated by fire, but this is an unproven theory at the present.

Pileated woodpecker

Input from the Klamath Tribes indicate more acres of pileated habitat were present during the reference

period than currently exist. Reference conditions contained more open pine stands with larger average

diameters, with more ponderosa pine suitable for nesting trees. Periodic low intensity/severity fire

maintained these stands in the reference period.

Spotted Owl

There appears to have been little reference era owl habitat as now defined. The only suitable habitat

would have been the stand replacement fir zones above 6200 feet, and narrow bands along the upper

forks of Trout Creek.

B. What federal activities have led to an increase or decrease in the quantity or quality of habitat

for TES species?

Fire suppression has increased the susceptibility of late seral stands (or areas) to stand replacement fire by

allowing brush and conifer species to occupy potential and suitable habitats. Organic material at or near

the ground surface has been able to build up beyond historic levels. Fire suppression tends to

discriminate against more shade-intolerant species. Increased stem density has raised stand susceptibility

to insect and disease infestation, and the potential loss of entire communities. Openings, both natural and

man-caused, are closing with vegetation increases.

Roads continue to be the prime threat to TES species and habitats. Occupancy of areas by roads reduces

available habitat. Roads accelerate runoff, reducing the system's ability to maintain water tables at levels

necessary for TES plants. Culverts affect streams, channels, and riparian areas by collecting and

accelerating delivery of water to the channel.

Grazing along some intermittent channels has reduced riparian hardwood occurrence through impacting

channel and meadow integrity through compaction and bank degradation. Non-native forage species

have been introduced for domestic animals and ungulate wildlife.

SOS Watershed Assessment 31


Some federal activities have maintained or allowed TES species and their habitats to increase. Fire

suppression benefits some species, such as wild onion. Old Growth Areas have been established, and

management activities have been excluded from other areas such as Saddle Mountain and the Badlands.

Areas adjacent to stream channels and meadows have also been excluded from most intensive

management activities. Road construction in riparian areas has been reduced. Implementing stricter

forage utilization standards for domestic livestock grazing, controlling noxious weeds, and limiting

introduction of non-native species for forage and erosion control have all been beneficial.to TES species

and habitats. In some situations, grazing may be favorable to some TES plant establishment. Harvest

and reforestation have affected late seral plant community composition and conditions.

C. What federal activities affect specific key habitats for TES species, and how are these habitats

affected?

Federal activities since the reference period have affected aquatic habitats within the Rock and Trout

Creek drainages.

Inland Redband Trout - Sensitive

Rock Creek

Rock Creek appears to have been a perennial system from the headwaters to the mouth in the reference

period. Construction of the Yainax Agency, the Rail Line that parallels the north slope of Bly

Mountain/Round Mountain highlands and intensive agricultural and grazing activities have caused major

physical alteration to both the upper and lower Rock Creek drainage. Trout habitat has declined in

quality and quantity since the reference period as a result of channel and system simplification.

The system is currently habitat for a resident population, but appears to be restricted to reach #4 and the

unsurveyed, intermittent reach between the top of Dams Canyon and private lands in Dams Meadow

during low water periods. There is a strong probability that a migratory population of trout occurred

prior to system alteration. Restriction now occurs as a result of the discontinuous perennial system.

During the recent drought, perennial flow occurred in reaches I and 4, but were physically separated by

several thousand meters of dry channel. Reach 4 is approximately 7,500 meters from the Sprague River.

Surface flow connects federal property with the Sprague River during periods of high water. The lower

drainage is lacking a single, distinct channel. Flow occurs overland across a broad meadow

approximately 500 meters long. Any movement is via shallow, discontinuous channels over a broad

expanse of grass/sedge meadow. Though hydraulic surface connectivity occurs in some years, the lower

system is sufficiently discontinuous to dissuade annual or seasonal migration.

The quantity and quality of habitat at low flow (typically August thru October) appear to be limiting this

population.

Instream cover: The quantity of pool habitat in perennial reaches is lower than the optimum

recommended by many authors. The riffle/pool ratio for reach 4 is approximately 10/1, indicating a

preponderance of glide and rapid habitat in this highly modified reach. The average pool depth in reach 4

is 0.4 meter.

Coarse woody debris (CWD) in reaches 3 and 4 is low (22 Pcs/Km), and nonexistent in reach 6.

Reaches 3 and 4 received a high degree of impact/alteration from railroad construction in 1928 and

1929. A railroad grade was constructed directly up the stream channel to access timber in the upper

SOS Watershed Assessment 32


watershed. Channel morphology in reach 6) contributes little to instream cover due to low angle banks

(less than 90 degrees), though several plunge pools occur at nick points in the channel system. The

duration of flow in reach 6 is unknown, but an ODFW survey in October, 1991, found no surface flow.

In July, 1992, strearnflow in reach 6 was sufficient to hold fish.

Water Quality: Water temperature in the upper system is a concern. The water temperature entering

Dams Canyon on May 24, 1995, was 20.50C. This temperature reflects the mixing of water from

tributary I and the intermittent reach above the private lands in Dams Meadow. Water within the

meadow may reach or exceed the upper lethal temperature (approximately 250 C) due to lack of shading

during periods of low flow.

Ground water enters reach 4 somewhere below the confluence of the mainstem with reach 5. An ODFW

survey recorded water temperatures in reach 5 at 14'C in October, 1991, and in reach 4 at 90C. Pool

habitats in reach 4 are the only refuge sites for redband trout at low water, but are low in quantity

(124m2; 10% of the wetted area) and quality (average less than 0.4m deep). No other data is presently

available.

Habitat Trend and Threats: In the publicly held portions of the drainage, habitat is in an upward trend.

Reach 6 exhibits a Rosgen F6 type channel which is beginning to form a C type channel. Instream cover

should improve as the channel deepens and the width/depth ratio in reach decreases. A decrease in the

width/depth ratio will favor lower temperatures during low flow as well.

In late May, 1995, intensive riparian hardwood planting occurred in reaches 5 and 6. Approximately 800

alder were planted within the F6 channels in an attempt to increase bank stability. Winema National

Forest personnel will conduct temperature monitoring to determine if lethal temperatures are occurring.

Trout
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