Chiiloquin ranger district

НазваниеChiiloquin ranger district
Размер2.84 Mb.
1   2   3   4   5   6   7   8   9   ...   14

Subwatersheds Within the SOS Area

Note: See Appendix B, Rosgen Stream Type for descriptions of characteristics for channel types

identified in the following subwatershed summaries.

The major channels in SOS display two basic profiles, depending on the terminus of the channel. Butler

Creek and Crystal Castle Springs both enter the Sprague River in the relatively steep canyon above the

town of Chiloquin. These drainages have their headwaters at the base of a headwall and move through

gently sloping valley bottoms (1-3%) for 1-1.5 miles. Gentle sections are separated by short (0.5 mile)

steep valley sections of 6-8% controlled by geologic formations of more resistant materials. The final 1 5

miles drop steeply (6-10%) into the Sprague River canyon.

Channels that end in the broad valley section of the Sprague have their headwaters on the steep valley

headwall below a flat plateau (Ya Whee) or a catchment basin (Choptie Prairie). These include

Copperfield Draw and Trout, Rock, and Whiskey Creeks. Often beginning as springs, these systems

follow a steep path (10%) down the headwall to the base, and then step between flat valleys 1-2 miles in

length through short sections of narrow, steep gradients controlled by geologic formations. Final sections

actually flow through the valley formed by the Sprague River, and most are diverted for agricultural use.

SOS Watershed Assessment I I

No Name Flat and Dockney Flat are relatively short drainages (4-5 miles) north of Ya Whee Plateau

between Saddle Mountain and Copperfield Draw These are intermittent systems that may have short

spring-fed reaches at their headwaters The spring source is likely the ground-water from Ya Whee

Plateau. Both drainage profiles consist of 2 mile sections of very flat valley at the confluence with the

Sprague, then gradually increased gradients to their headwatersi

Copperfield Draw is experiencing downcutting and streambank erosion in the lower reaches and in

Wright's Meadow Headcuts can start at the top of a system and work down, or at the bottom of the

system and work up It appears that headcuts have run through the Copperfield system three or more

times, and this continues at a moderate rate.

See Appendix C, Functional Condition of Streams Examined In Copperfield Subshed, for a summary of

the Conditions in the Copperfield Subwatershed. It should be noted that the functioning condition calls

were made by technicians not fully trained in the protocol, and may be subject to change when examined

by the appropriate experts.

Soil pedestals are prevalent in the upland slopes of Wright's Meadow. Grazing has greatly reduced native

vegetation. Wind and rain have eroded away the fine soils between the vegetated pedestals, and erosion

pavement exists. These areas are less pervious and it is difficult for vegetation to become established, a

pattern typical in semi-arid climates. Where subtle microgradients of the meadow meet, surface run-off

concentrates and headcutting starts. The downcut continues to run down the channel, creating a gully.

A lowering of the grade downstream can initiate a nick point thlat works it's way upstream. It may have

been induced when a railroad or a road was constructed. Natural geologic formations or beaver dams

may also have initiated the process. The drop in grade creates a scour pool downstream, intensifying the

headcut. Side channels run into the gully and a new nick point begins. High run-off accelerates the


Water yield and hydrograph information should be analyzed todensure restoration efforts meet their

objectives. Attempts to control headcutting are successful only when the capacity of the structure is

adequate. If more water goes through the system than it was designed for, scour or structure failure will

occur. The change in grade below a structure or physical feature must be considered. Lowering of the

grade through step pools, or lengthening of the channel are necessary to prevent scour pools and

headcuts. Breaking the concentration of flow is necessary to control erosion. Vegetation is a key

element in the restoration effort. Proper land management is vital for restoration to occur and the entire

watershed must be considered. There are numerous old flow retarding structures in Copperfield Draw,

most of which are no longer functional, and have created scouring around the structures. Exclosure

fencing is down or in disrepair in many areas. The remnants of these structures (metal posts, fencing

material) are scattered throughout the channel, are unsightly and ineffective, and should be removed.

For more thorough descriptions of SOS subwatersheds, with channel typing and profile and gradient

graphs, see Appendix D, Subwatersheds.

SOS Watershed Assessment 12

2. How have fire exclusion, grazing, timber harvest, road construction, railroad

construction and other management activities changed the biological and physical

elements of the landscape from the reference condition?

A. What aspects of these activities mimic reference processes?

Management activities have affected ecosystem functions in many ways. Some aspects of management

activities mimic natural processes- of the reference period, but in most cases, the similarities are very


Fire exclusion is a management activity that provides no similarities to the reference period. Fuels are

allowed to accumulate and understory and overstory vegetation is allowed to occupy sites at densities far

beyond reference period levels. Nutrient cycling processes are being dramatically altered (ecosystem

nutrients are gradually being bound in organic form).

Grazing offers scant similarities to reference period processes. Nutrient cycling occurs on site, although

at a much lower level than during the reference period. A significant portion of ecosystem nutrients are

immobilized in animal form and transported off site. Wherever intensive grazing occurs, floristic

composition is gradually moving toward greater amounts of woody plants at the expense of herbaceous


Timber harvest can mimic some of the structural dynamics of the reference period. Understory thinnings

are similar to low intensity underburms of the reference period. In mixed conifer, small group selection

(or even small clearcuts up to 30 acres) provide forest structure changes which reflect those created by

periodic wildfire in the reference era. However, the.exportation of carbon and other nutrients off-site

provides a much different nutrient cycling process than during the reference period.

Road and railroad construction have no reference period analogues with regard to ecosystem processes

and functioning.

B. How have vegetative conditions changed since the reference era?

BIA records, reports by Lieberg and Munger (see Appendices E and F), and a 1920 cruise were all used

to develop the reference era descriptions for forest types. Most available information refers only to

timber types - ponderosa pine in particular. It is important to remember that both reference and current

condition are not static, so ranges are expected to have changed over time.

Conditions (and ranges) come and go as natural or human caused disturbance events occur, and as the

vegetation responds to those events.

Forest Communities

Lodgepole Pine

Lodgepole is present as a minor species in both reference and current stands. There are very few acres of

LP type within the assessment area, so the type will not be addressed further.

SOS Watershed Assessment 13


Stand Replacement Fir

This type occupied less than 4% of the watershed acres during the reference period, with stand

compositions basically the same as today. The 1920 cruise showed this type as all in a climax condition.

Today, this type occupies nearly 45% of the watershed, and may contain a higher proportion of mature

rather than earlier seral stands, with higher stocking levels than in the reference period. This has resulted

primarily from fire suppression lengthening the interval between stand replacement fires.

areas with 50% or more total stand volume In DF and WF

data from first BIA cruise (1 WU-41

Input Is by section

) , % ..


~~~~ ...C.


The above map shows the approximate location of reference era stand replacement pine/fir types. The

1920 cruise indicated all were high-volume (20-28MBF/ac) climax fir types (the Swan Lake Fire altered

this in the 1940s). Unshaded areas show the extent of the reference period ponderosa type.

Ponderosa Pine

This type covered over 90% of the watershed in the reference era, but today covers only about 46%.

Stands with less than 50% fir were generally in an open canopied condition dominated by a continuous

large-tree structure with occasional clumps of reproduction (up to 5 acres). Trees were often growing in

clumps of 2 or 3, with 50-100 foot openings between the smal~groups or trees. Ponderosa pine roots

can occupy a large area, often reaching out 100 feet or more, so it is likely these supposedly open areas

may well have been 100% occupied by large tree root systems. Proportionately less growing space was

occupied by conifers, with grasses, sedges, and brush covering a larger percentage of area within the

stands during the reference period. Today, this is reversed, with tree stocking levels 2-4 (or more) times

those in reference period stands. This is generally true for all of this type, except where clearcuts less

than 15 years old, and stand replacement fires have occurred.

SOS Watershed Assessment 14

Information regarding understory stocking in the reference period ponderosa stands is very limited Plot

data from 1936 and 1948 (BIA Archive Files) for the South Calimus and Wildhorse Ridge areas, shows a

range of 9 5 to 17 trees/acre larger than 12" DBH Though not in SOS, the data is considered

representative of pine sites within the dnalysis area. Anecdotal notes and inventory entries during this

period often comment on a lack of understory vegetation. The Long Prairie cut-over cruise recorded 2 8

small poles (4-7") and 3 4 large poles (8-12") per acre, and noted these were in clumps.

Data from the 1899-1920 period is considered sufficient for determining the reference period conditions,

since most of the local forests were relatively untouched at that time. The seedling component may have

changed, but it is doubtfuil. References scarcely mention older seedlings, but do address the open

characteristics of most stands Our knowledge about fire frequency and intensity supports the theory

that the understory component burned on a regular basis during the reference period, limiting seedling


Cochran, in one limited study, has demonstrated that individual ponderosa pine growth rates increased

since the advent of fire suppression, but with an overall loss of the species. Reasons are still unknown.

The increased growth may be due to less competing vegetation (increased surface litter may be causing a

reduction in the availability of growing sites), or a soil productivity increase due to increased moisture

holding capacity or nutrient availability. Much more research is needed on this subject.

The pine type dominated most upland areas, with stand volumes ranging from 5-20+MBF/ac. (average

I OMBF). High volume stands occurred in higher elevation and moisture regime areas, and contained

more sugar pine, Douglas fir and white fir.

The table below displays five stand conditions for comparison of stocking level parameters - basal area,

trees per acre, and Stand Density Index (SDI). The M&M Uneven-age Demo Area (M&M) is not in

SOS, but is included as a reference because it is well known and represents a type of stand common to

SOS. The Current Uneven-Age Management Prescription (Current Rx) is included to show that most

current harvests still leave stand stocking levels at higher densities than the reference condition. The SDI

has been used here because it is a more accurate measure between differing stand types.


M&M 80 232 140 More highly stocked next to road.

Current Rx 60-80 75-150 + 70-120 If stand is not pre-commercially

Current Stands 60-200+ 100-400+ 100-400 thinned values can be much higher.

Reference Stand 28 7.58 35 Reference stand computation based

(5 MBF) on arbitrarily selected 26" DBH 4 log

Reference Stand 50 15.15 70 tree.

(10 MBF)

SOS Watershed Assessment 15




, ;, :,Aigs ' "- " * ' '4 y-' tS ~ ~ ~ ~ ~ ~ ... ~-

N5 -4,

The above map shows stands which, in the reference period, had at least 15% Douglas-fir or white fir.

The one section at the lowver center is missing data, but likely had a 15% fir component. The remainder

of the area was ponderosa pine, incense cedar or very minor anmounts of lodgepole pine. (See Appendix

G, 1920 Cruise Volume Distribution Maps, for additional maps showing 1920's cruise volume.)

During the reference period, most trees were 14-30" DBH, with some trees reaching 60-80" DBH. From

the initial BIA through the present harvests, residual trees would have had opportunity (reduced

competition) to grow to much larger diameters. There may be as many (or more) extremely large DBH

trees in current stands as were in historic stands. At present, tltere are fewer 20-30" DBH trees in SOS

stands than were in the reference period stands. However, the "inventoried old growth" stands would

contain as many 21 "+ DBH trees as the reference condition, but the average diameter of the 20-40"

range is smaller. (See Appendix H, Subwatershed Current Conditions, for statistical data on present

subwatersheds conditions.)

(Note: The use of value judgment terms such as low, high, overstocked, and understocked are relative

to an objective. Not using value terms can result in lengthy descriptions. For this analysis, overstocked

will be used to identify conditions that are not sustainable without major human interventions; or will

sustain a major stand replacement event where stand replacement events were not the reference


The following charts illustrate the progression of stands from pine dominated (reference condition) to the

point where they are converting to stand replacement fir types. Today's stands contain significantly

higher percentages of white fir and Douglas fir, and maintain dense understories. These stands are highly

overstocked and in a state of stress as a result.

SOS Watershed Assessme(nt 16

PorKldrosa Pro Progression

% watershed. Trout. He

Ponderosa Plne ProgrssonI

%of warihM, L Corb -* Rides













1   2   3   4   5   6   7   8   9   ...   14


Chiiloquin ranger district iconSu bwatersheds chiloquin Ranger District Winema National Forest

Chiiloquin ranger district iconAps district high school health curriculum framework c ourse Title: P. O. W. E. R. – Philosophy of Wellness that Enriches Relationships District Course Number: 063TF

Chiiloquin ranger district iconOn Appeal From a Judgment of the United States District Court for the Eastern District of Missouri, Eastern Division September 24, 2002 *

Chiiloquin ranger district iconI. stature, purpose, and adoption and revision of procedures: Official procedures of District 55, as adopted from time to time by the District Council, are set

Chiiloquin ranger district iconLake George and Seminole Ranger Districts

Chiiloquin ranger district iconDistrict 41 Directory

Chiiloquin ranger district iconHistory of the Third Masonic District

Chiiloquin ranger district icon1 in the united states district court

Chiiloquin ranger district iconStandard for district success 1: curriculum

Chiiloquin ranger district iconRiverside Community College District

Разместите кнопку на своём сайте:

База данных защищена авторским правом © 2014
обратиться к администрации
Главная страница