Chiiloquin ranger district




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Creek

Trout Creek is one of the principle watersheds within the SOS. All three forks of Trout Creek are

perennial, though discontinuous flow was recorded in mid October, 1991. This stream system appears to

be in an upward trend, recovering from intensive earlier farming activities. The three forks of Trout

Creek contain habitat that is rare on the Chiloquin Ranger District, and support resident populations of

redband trout.

Some fish in this system may migrate to the lower reaches and/or the Sprague River. The upper reaches

or the North Fork are very low in pool habitat and habitat complexity, whereas the lower reaches of the

mainstem contain deep pool habitat and are in contact with the Sprague River.

Instream cover: In 1991, reach 1 was dominated by 3 deep (1.3m) backwater pools which appear to

have been beaver impoundments. The large dams have apparently been breached and replaced by smaller

structures, four of which appear to be the result of recent beaver activity. Pool habitat in reach 2 is high,

with a riffle/pool ratio of 5/1. Habitat complexity is increasing through the addition of CWD from the

1987 Cowboy Fire.

Pool habitat in the North Fork is lacking. The average riffle/pool ratio is 16/1. The substrate in these

reaches is dominated by sand (31%) and silt/organics (30%), with 27% of the substrate being gravel. All

of the North Fork reaches received low wood complexity scores during the 1991 ODFW Survey.

SOS Watershed Assessment 33


The middle fork of Trout Creek is dominated by a large moist/wet meadow Though altered by

agricultural activities for over 70 years, this fork appears to be in a distinct upward trend Habitat

supports a population of redband trout in the mid e reaches of this system. It is unknown if the

population is migratory, resident or both. The no ;le fork was not surveyed by ODFW in 1991, but the

team managed to visit sites along its course.

From the confluence upstream to the culvert/road crossing at the ranch site is a Rosgen C channel. This

channel exhibits some incision and lateral movement into the historic floodplain, now a terrace. The

width/depth ratio appears fairly high, though diagnostic measurements have not been made. In-channel

habitat is low, but increasing through the development of willow sites and debris jams.

From the road crossing to the irrigation head gate at the top of the main meadow, the channel bisects a

large open meadow with a narrow, deep channel. The width/depth ratio is very low. Sinuosity appears

to be increasing, as do undercut banks. Willow is prominent in the lower end, but sparse in the upper

end.

Downstream from the irrigation head gate, channel straightening has resulted in a short (100m) section of

stream that is low in habitat complexity. A possible (low priority) restoration project could occur here:

Remove the head gate and route the stream (in a sinuous pattern) back to a prior channel.

From the headgate upstream encompasses a variety of habitat types, with sections of different substrates

and gradients. An impoundment created a well developed hardwood community over a branching,

narrow channel in the lower portion of this reach. Upstream, the gradient increases sharply.

The south fork of Trout Creek may be the best representation of pre-management conditions in the south

block of the Chiloquin Ranger District. Little is known about this fork from Section 15 down stream,

but the entire south fork will receive a USFS level II survey during the 1995 summer field season..

Within section 21, habitat and water quality appear to be excellent.

Water Quality: Temperature measurements were taken at or near the confluence of the north and south

forks in 1975 and 1976 . Water leaving the south fork was typically warmer than that leaving the north

fork. In mid July 1976, the temperature of water exiting the south fork was approaching the upper lethal

temperature for trout at 250C. Temperatures recorded during the August 1979 ODFW contract surveys

were considerably cooler at 220 C. High temperatures in the south fork above the confluence may

represent a seasonal barrier to movement.

Northern Spotted Owl - Threatened

There are two nest sites located in the SOS area. Observations of spotted owls on the Chiloquin Ranger

District date from the late 1970s and 80s, some of which were recorded in the assessment area. The

identification of nesting owls eventually resulted in a modification of the eastern range line of the owl as

presented in the ROD (1994), and adoption of a management strategy for the south block of the

Chiloquin Ranger District that was developed for westside forests. Managing the South Block as spotted

owl habitat may involve attempting to manage for an entirely different percentage, as well as stem

densities, of white fir and Douglas fir than was present in the reference period.

Habitat suitability for the northern spotted owl and other late seral related species has most certainly been

affected by management activities, specifically the exclusion of wildfire from the landscape. The spatial

extent of habitat islands fluctuated over time in response to subtle and major changes in weather patterns,

fire events and, more recently, management activities.

SOS Watershed Assessment 34


A forest inventory cruise conducted from 1920 through 1924 indicated a comparitavely large block of

timber was dominated by white fir/Douglas fir on the north slope of Swan Lake Point, which may have

been suitable habitat for spotted owls. Smaller habitat blocks were associated with the upper reaches of

the Trout Creek drainage. Several thousand acres on the Ya Whee Plateau contained varying amounts

(> 15% of the total stand volume) of white fir and Douglas fir, but dominated by Ponderosa pine (see p.

26).

That local birds exist in total isolation from larger source populations is highly unlikely. The south block

of the Chiloquin Ranger District is a sink for dispersing birds from a source population in the southern

Oregon Cascades. Spotted owls that dispersed into the south block during the reference period or since

fire supression crossed large areas of unsuitable habitat (Klamath Lake, Agency Lake). Fire suppression

did not alter the size of these unsuitable habitat areas, so there is no reason to believe that dispersal into

the south block did not occur during the reference period, much as it does now.

A viable, breeding population of spotted owls probably did not occur in the south block prior to

management activities. Without regular immigration to the south block from a larger, source population,

extinction for this local population will, and probably has, occurred. Small scale, stochastic events (fire,

local disease) could easily force this population to extinction at any time.

Fire exclusion on a broad scale is believed to be the greatest threat. This activity has created and

maintained stands that have a greater susceptability to stand replacement events - fire, disease and

outbreaks of insects - more so than during the reference period.

Bald Eagle - Threatened

Historic timber harvesting and road construction removed large conifers, reducing nesting habitat. Road

construction reduced effective nesting territories. Rail and road systems were constructed across stream

channels, which reduced habitat for their prey base (fish and waterfowl) lowering water tables and

changing water flows. Grazing removed and/or reduced stream bank stabilizing vegetation. DDT and

1080 affected eagle reproduction prior to their use being banned.

Present federal management has allowed improvement of conditions for bald eagles by restricting harvest

activites and timing near active nests. Eagle nesting areas have been established and are monitored

according to the W.N.F. L.R.M.P (1990). Use of pesticides within the vicinity of nests is prohibited.

Grazing activities adjacent to perennial fish-bearing streams and wetlands have been reduced or

eliminated on federally administered lands in SOS.

Present federal activities which contribute to a decline in habitat effectiveness, as well as placing nesting

habitat at risk, continue to occur. Long-term fire suppression and an over abundance of roads are the

primary factors. Road densities in eagle management areas are not being reduced. Management plans

are not in place to reduce fire hazards in active nesting territories.

The major potential threat to present bald eagle habitat continues to be fuel loading build-up.

Open roads in management areas facilitate harassment by allowing vehicles to enter during the nesting

season. The de-watered condition of former wetlands, and lowered water levels in streams

do not provide suitable habitat for the eagles' prey base.

SOS Watershed Assessment 35


Past activities which have, and future activities which may impact the habitats of TES Species are

common to the species listed below. A description of the activities and the consequences, both negative

and positive, follows the list.

American White Pelican - Sensitive

Greater sandhill crane - Sensitive

Northern Goshawk - Winema Indicator Species

Fisher - Category 2


Negative Impacts

The primary management activities that pose threats to habitat are fire suppression and roads. Current

standards for fire suppression cause the build up of forest litter, and the retention of over stocked stands.

The greatest threat to habitat is in the potential for a large fire within the watershed which could

conceivably eliminate all habitat for any given species Retention of current transportation systems

continues to negatively impact water tables and stream channels in meadow systems. Lack of restoration

activities in many degraded stream channels facilitates the continuation of channel degradation.

Past federal management activities that reduced habitat were the channelization and diking of the Sprague

River, which reduced wetland area within SOS. Water runoff was accellerated during spring thaw, and

timing and duration of flows was altered. Some perennial stream portions became intermittent.

Streamside vegetation was removed primarily for the development of grazing capacity. Domestic

livestock grazed out stream cover, while other vegetation was removed with tractors and drag lines.

Increases in road density directly affected riparian and streamside vegetation by occupying the space, or

by altering hydrologic function to the point where water tables are no longer accessible to strearnside

vegetation. All this has contributed to the diminishing of feeding area within the watershed.

Fire suppression continues to jeopardize (large fire potential) more mid and late seral conifer stands,

which may potentially reduce both nesting and foraging habitat for goshawks. Maintaining roads near or

in goshawk nesting areas continues to discourage occupancy and breeding activities..

Positive Impacts

Stricter enforcement of livestock forage utilization in meadow systems has reduced the impacts to habitat

on public lands. This is being accomplished on federally administered lands within the watershed through

allotment administration, but must be a voluntary effort where private ownership is concerned. Less road

construction near riparian areas, and a restriction of management activities in or near meadows would

also improve the condition of habitat.

Designation of management areas has probably been the best management activity to benefit some species

(such as the goshawk, for example). Restriction of management activities near active nests (distance and

season) have also proven beneficial. Other positive steps have been to reduce harvest volumes,

providing additional snag areas, and a reduction in road construction in areas frequented by goshawks.

Amphibians: At the present time there are no listed amphibians occurring within the analysis area.

Historically, the only current listed species that may have occurred in this area is the spotted frog, but due

to the large scale alteration of riparian habitats since 1900, there is no longer suitable habitat present.

Reptiles: The northwestern pond turtle probably occurred in the analysis area. Again, due to the

lowering of water tables, it is doubtful that this species presently occurs.

For a complete Winema National Forest TES list see Appendix L, WNF Threatened and Endangered

Species.

SOS Watershed Assessment 36


5. Has soil compaction increased and what impact has this had on vegetation?

No comprehensive study or intensive monitoring of soil compaction and vegetative impacts have been

done within the SOS area. Based on the physical nature of the area's soils, an understanding of the

compaction process, and some personal observations, it is safe to say management practices have caused

an increase in the amount and severity of soil compaction within the assessment area. Whether this has

been detrimental or not cannot be determined from available information.

The SRI (Soil Resource Inventory for the Winema National Forest. Carlson, 1979) identifies and

describes several different land types and complexes occurring within the area. Susceptibility of the soils

to compaction during management activities are variable. The B-Group soils are rated as having low

susceptibility, while the H-Group is rated as low through high, depending on the rock volume within the

individual soil profile. It should be recognized that the SRI is a reconnaissance level soil survey and does

not have the scale or detail to be employed on more intense planning levels. Therefore, it is conceivable

that the compaction susceptibity, especially for the B-Group soils, may be understated.

Evidence to support this statement is found in the soils monitoring program in progress on the Chemult

Ranger District, north of SOS. Compaction monitoring on several hundred acres of similar soils (both A

and B Groups) has established that compaction is present on every management area tested (mostly

timber sales). Each timber sale monitored had some degree of severely compacted soils, most were

between 10 and 50 per cent compacted and overall averaged about 30 percent severely compacted, not

including roads.

It appears that if ground-based machines were employed during harvest operations, soil compaction

resulted. On most of the units monitored in Chemult, severe or detrimental compaction exceeded forest

plan standards and guidelines for soil impacts. Further personal observation of limited areas within the

watershed revealed areas with highly compacted soils, which appeared to be the result of machine

operations during timber harvest.

As stated previously, it is safe to assume that soil compaction has increased in response to management

operations and that it has impacted vegetation to a certain unknown degree. We now need to establish a

comprehensive soils monitoring plan to ascertain distribution, severity and effects of the soil disturbance.

Many studies have delved into the vegetative impacts of soil compaction, but none have been done on the

Winema National Forest. Most of the studies have concentrated on the impacts of compaction on timber

species, although some range studies have centered on the effects of compaction on meadows and

riparian zones due to livestock grazing. Primarily, the timber studies were designed to detect losses in

timber volume (height and diameter) for a given area, losses in germination and seedling establishment,

and early growth rates on compacted soils compared to undisturbed soils. Some examples of these

studies include:

Helms and Hipkin measured Bulk density (Db) around 423 ponderosa (California Sierras). They

found a Db increase of 43% on landings, 30% on skid trails, and 18% on adjacent cut over areas.

Tree volume per unit area was reduced 69, 55, and 13% respectively.

Steinbrenner and Gessel (S. Washington Cascades), found a 24% increase in Db on tractor-logged

lands, a 35% loss of permeability, and a 10% decrease in macropore space. Skid trails showed a Db

increase of 2.6-133.6%, a 53% loss in macropore space, and a 93% loss in permeability. An average

of 1260 seedlings/acre were established in cutover areas, but only 410 seedlings/acre on skid trails.

SOS Watershed Assessment 37


Forristal and Gessel (Snohomish County Washington) noted that Douglas fir and Western hemlock

root growth was restricted significantly by a Db of approximately 1.25 g/cc.

*Minore et al, in green house studies, compacted soils to 1.32, 1.45 and 1.59 g/cc and planted trees

into these compacted soils for two years. They found that all seven northwest tree species roots

would penetrate into the 1.32 g/cc soils; Western redcedar, Sitka spruce, and Western hemlock could

not penetrate 1.45 g/cc, while White fir, Lodgepole pine, Red alder and Douglas fir could. None of

the seven species penetrated into the 1.59 g/cc Db.

Lanspa (Six Rivers N.F.) noted tree heights of 27.3 inches on skid roads, and 71.4 inches on adjacent

cutover areas. He attributed most of the difference to soil compaction inhibiting growth.

In Oregon, Power found that compaction in coarse-textured soils persisted for at leasr40 years.

Changes in crop tree germination, seedling survival, and tree growth rates are generally used to measure

changes in vegetation due to soil compaction in most studies. It appears that actual changes in vegetation

types, unless blatant, have been ignored. Some range compaction studies may have identified vegetation

changes. It may be that the study of compaction is still a fairly young field, and changes are not evident

enough or of sufficient importance to justify identification.

SOS Watershed Assessment 38


6. Has soil productivity increased or decreased since the reference period? What

impact has this had on vegetation?

A.
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