Klamath Ecological Province





Klamath Ecological Province in south-central Oregon lies mostly in western Lake County and southern Klamath County with a very small portion in southeastern Jackson County. In Oregon, the province covers about 2.7 million acres. It extends south into Siskiyou and Modoc counties in California.



Physiographically, Klamath Province in Oregon is typified by large basins consisting of lakebeds surrounded by extensive ancient lake terraces which are interspersed with basaltic mountainous terrain. Existing lakes in Oregon include Upper Klamath Lake, Agency Lake, and the northern third of Goose Lake, plus two large reservoirs, Drews and Gerber. In California, the province includes Lower Klamath Lake, Tulelake, Clear Lake, and the southern two-thirds of Goose Lake. Upper Klamath Lake drains to the south through Klamath River. Goose Lake seldom overflows, but when it does it drains south into Pit River.

The highest elevations in Klamath Province in Oregon are in the north–south chain of basaltic mountains, Warner Mountains, east of Lakeview in Lake County. These include Drake Peak, 8,405 feet; Light Peak, 8,220 feet; Twelvemile Peak, 8,080 feet; and Crane Mountain, 8,446 feet. In the western portion of Lake County, high elevations in the province include Dead Indian Mountain, 7,060 feet; Winter Rim, 7,280 feet; Slide Mountain, 7,840 feet; Coleman Rim, 7,470 feet; Cougar Peak, 7,925 feet; and Grizzly Peak, 7,775 feet. None of these peaks reach timberline.

The portion of Klamath Province in Klamath County is less mountainous than in Lake County. High elevations include Fishhole Mountain, 7,020 feet; Horsefly Mountain, 6,480 feet; Yainax Butte, 7,240 feet; Saddle Mountain, 6,835 feet; Swan Lake Point, 7,320 feet; Haymaker Mountain, 6,585 feet; and Stukel Mountain, 6,525 feet.

Lowest elevations in the province in Oregon are in Klamath County—Malin, 4,050 feet; Merrill, 4,070 feet; Klamath Falls, 4,100 feet; and Klamath Lake, 4,136 feet. In Lake County, the lowest elevation in the province is along the line of demarcation between Klamath and High Desert provinces from the vicinity of Valley Falls to near Paisley. This line lies at about 4,500 feet elevation. Goose Lake is 4,680 feet and Lakeview 4,746 feet elevation. (Elevations are from USGS 1:250,000 topographic maps.)

Lake basins and terraces occupy about 50% of the land area of the province that lies in Klamath County and about 20% of the province that is in Lake County. Lake basins and terraces in both Lake and Klamath counties are used primarily for irrigated agriculture. The remainder of the province in Oregon consists of rangeland and forest.



Noncultivated upland soils typifying the Lake County portion of Klamath Province are derived primarily from tuffaceous and basaltic materials. Sagebrush–bunchgrass rangeland soils are primarily the Booth–Bluejoint soil association, which are clayey soils, and the Hapgood–Hartig soil association, which are loamy soils. Pine- and fir-forested soils are primarily the Woodcock–Mound soil association, which are well-drained loamy soils. Soils being cultivated, mainly under irrigation, on terraces and fans in the Lakeview vicinity are typically the Drews soil series. Soils on well-drained bottomlands are in the Lakeview soil series. Poorly drained flood plains include the Goose Lake, Scherrard, and Stearns soil series, the latter two being alkaline.84

In the Klamath County portion of Klamath Province, the major rangeland soil is Lorella series, which is formed in tuffaceous and basaltic materials and grows juniper, sagebrush, and bunchgrasses. The Merlin soil series represents the major low sagebrush scabland site. Forested areas are associated primarily with Woodcock, Pokegema, and Turnquist soil series, which are formed in andesitic parent materials.

Various soil series are associated with the extensive valleys and low terraces that are cultivated, mainly under irrigation, in the Klamath County portion of this province. The soils are formed in lacustrine sediments consisting of tuffaceous and basaltic materials and are represented by such soil series as Malin, Scherrard, Bedner, Calder, and Laki. Fordney series occurs in sandy basins and fans. Soils that are poorly drained include Ontko, Klamath, Pit, Henley; some are alkaline. Marsh soils are represented by Tulano, Algoma, Yamsay, and Moyina series, which are formed primarily in lacustrine diatomaceous materials. The Tulano series, where drained, probably is the most extensive cultivated soil in Klamath Province.79



Based on eight official weather stations representing Klamath Ecological Province in Oregon, average annual precipitation for the Lake County portion of the province is 14.2 inches, of which 35% falls during the herbaceous native-plant growing season, April through July. The average annual precipitation for the Klamath County portion of the province is 14 inches, of which 27% falls during the growing season. October through March (winter) precipitation for the province is about 61% of total precipitation in Lake County and 66% in Klamath County. Average temperatures do not vary significantly between Lake and Klamath county weather stations. Average January maximum and minimum temperatures for the province are 37.8 and 16.4°F, respectively. Average April through July maximum and minimum temperatures for the province are 70.9 and 38.9°F, respectively.

A precipitation map53 shows a precipitation high for the province of about 65 inches annually in the Crane Mountain area southeast of Lakeview, which is also the highest elevation in the province. A few mountainous areas scattered throughout the province show average annual precipitation above 25 inches; the south portion of Winter Rim shows about 35 inches. The most arid part of the province is near the California state line at Malin and Merrill, southeast of Klamath Falls, where annual precipitation is about 10 to 12 inches.



According to the 1936 State of Oregon Forest Type Map,54 which predates extensive logging activities, about 70% of the Lake County portion of Klamath Province was covered by trees, primarily ponderosa pine. A small area above about 7,000 feet elevation southeast of Lakeview was forested with such species as true fir. About 30% of this portion of the province was unforested. Of that, about 5% was cultivated, 5% was lakebed in the vicinity of Lakeview, and the remaining 20% was likely shrub–grassland. Only about 1% of the Lake County portion of the province was covered by stands of juniper. These stands were mainly in two locations, about 12 miles west of Lakeview and south of Highway 66, and on the rocky plateaus sloping east between Warner Mountains and Warner Valley.

In the portion of Klamath Province in Klamath and Jackson counties, about 50% was covered by trees consisting primarily of ponderosa pine. In addition, about 10% of the area was covered by stands of juniper distributed throughout the area. Unforested areas, which were probably cropland and shrub–grass rangelands, covered about 40% of the area; and lakes, marshes, and wet meadows occupied about 10% of the area.

Radical changes since 1936 in Klamath Province of Oregon include expanded juniper coverage and increased cropland acreage resulting from sprinkler irrigation and the drainage of marshes and shallow lakes.

Natural grasslands in Klamath Province of Oregon occur only on bottomlands, and the vegetation varies according to degree and duration of wetness. The driest natural grasslands in Klamath Province are well-drained bottoms on which basin wildrye dominates a wide variety of grass species. Associated soils include the Modoc series. The wettest natural grasslands in the province are wet mountain meadows on which tufted hairgrass dominates in a wide variety of grasses, sedges, and rushes. Associated soils include Gooselake, Klamath, and Lakeview series. Meadows of intermediate wetness are dominated by a variety of bluegrasses, including Leiberg, Nevada, Kentucky, Canby, and Sandberg, and a wide variety of other grasses, sedges, and rushes. Associated soils include Whitworth and Yocum series.

Marshlands, the transitions from lake to meadow, are typified by bullrushes and cattails. Associated soils include Tulano, Algoma, Yamsay, and Moyina series.

Natural shrub–grasslands occur within the lake basins of Klamath Province in Oregon mainly on lakebed terraces and stony sloping tuffaceous plateaus and on some south-facing slopes at lower elevations in mountainous areas (Fig. 29).

Figure 29: Rangeland on ancient-lake terraces in the easter portion of Klamath Province, Oregon

Shrub–grasslands on very shallow or claypan soils are strongly dominated by low sagebrush with minor amounts of shrubby buckwheat and bitterbrush. Associated soils include Lorella and Booth series.

Klamath Province shrub–grasslands on moderately deep soils are notable for their wide array of shrub species. Big sagebrush and bitterbrush are widely prominent. Other shrubs include Klamath plum, serviceberry, desert gooseberry, shrubby buckwheat, gray horsebrush, gray and green rabbitbrushes, curlleaf mountain-mahogany, chokecherry, wax currant, granitegilia, rose, mountain snowberry, blue elderberry, oceanspray, and, on steep north exposures, birchleaf mountain-mahogany.

The Klamath Province shrub–grasslands also are notable for the wide variety of perennial grass and forb species in plant communities. It is not uncommon for a sizable plant community in relatively good ecological status to contain about 10 perennial grass species and about 20 perennial forb species. Soils associated with shrub–grasslands in the province in Oregon include Calimus, Bluejoint, Drews, Hartig, Lorella, Crume, Modoc, and Nuss series.

Most shrub, grass, and forb species in this province in Oregon are the same species found to the east and north in other Oregon ecological provinces. However, at least three species common in Klamath Province in Oregon do not grow in other eastern Oregon provinces: woolly wyethia, Klamath plum, and birchleaf mountain-mahogany. In its wide variety of shrub, grass, and forb species, Klamath Province represents a transition between other eastern Oregon provinces and Siskiyou Province in southwest Oregon, which also is typified by a wide variety of native species many of which apparently do not occur in eastern Oregon.

Natural juniper sites are considered to be those on which mature juniper trees constitute 5% or more of canopy cover and in which all age classes of juniper appear, indicating the stand’s perpetuation. East of Warner Mountains in Lake County, natural juniper stands occur on extensive areas of basalt rubbleland—land where rock outcrops and stone-size rubble cover about 90% of the land surface. Plant growth is confined to areas between the rubble; low sagebrush is the dominant shrub (Fig. 30). These areas are likely the same areas that were mapped as juniper trees in 1936. Similar examples of natural juniper stands also occur to the west in the province. Associated soils include the Hart–Rockland and the Lorella–Booth–Rockland complexes.

Figure 30: Managed natural shrub-grassland on very stony land producing Idaho fescue, low sagebrush, and scattered western juniper in the eastern portion of Klamath Province, Oregon

Other natural juniper stands are on undulating south-facing slopes having shallow, stony soils. Bitterbrush, big sagebrush, and a variety of bunchgrasses grow in the understory. Associated soils include Lorella and Fuego series.

In addition to juniper, stands of other coniferous trees in 1936 covered about 70% of Klamath Province. In this area, ponderosa pine is the most widespread tree species and grows in a variety of environments because of its wide ecological amplitude. In Klamath Province, it appears that ponderosa pine can encroach into disturbed forests, including into stands of white fir.39

White fir is the next most widespread tree species in the province. (Both white fir and grand fir are collectively called white fir in this instance.) Commonly, a single tree will have needle characteristics of both species, indicating that cross-breeding has produced a hybrid. This also occurs in Blue Mountain Province of Oregon where the two species intermingle. Fred Hall, an ecologist in Region 6 of the U.S. Forest Service (Portland), once aptly suggested the hybrid should be classified as Abies grandcolor to dispense with debate (personal communication to author). The ecological amplitude of white fir in Klamath Province in Oregon extends from the dry ponderosa pine zone, where it is normally on north exposures, to high cold ridges of about 6,700 feet elevation.

Douglas-fir is common only in the western portion of Klamath Province. Sugar pine extends throughout the province but is not dominant in any stand. It usually is on north-facing slopes in the province east of Klamath Falls and on south-facing slopes west of Klamath Falls. It appears to be somewhat tolerant of shade and always grows in mixed stands. Incense cedar generally is associated with sugar pine in Klamath Province in Oregon.

Lodgepole pine is uncommon in Klamath Province but grows in cold areas above about 6,700 feet elevation, such as on Swan Lake Point and Yainax Butte. It also occurs in concave cold and wet locations.

Soils associated with pine, fir, and mixed pine-fir forests include Mound, Woodcock, Tournquist, Lobert, and Bly series.

Aspen is the most abundant and widespread native deciduous tree in the province and is restricted to cold, wet areas. Soils associated with aspen stands include Mitten Springs series.

The greatest abundance of tree species, and for that matter of all plant species, is in the far western, most moist portion of Klamath Province in Oregon. This area is close to the Siskiyou and Cascade provinces.


Management Implications

The geomorphology of many soils in Klamath Province in Oregon is related to ancient sedimentary and tuffaceous lakeshore terraces and basins. These soils generally have loamy surface layers and loamy to clayey subsoils. The surface is often stony or gravelly, and hardpans may be present. These features are important to irrigated cropland agriculture on sloping lands.

Much of Klamath Province rangelands in Oregon are typified by basalt stones and outcrops on the surface, especially on upland slopes and plateaus. Associated soils commonly are shallow over clayey subsoils. These soils erode readily when herbaceous cover is depleted. Stones, exposed by erosion, can form a stone pavement which seriously impedes reestablishment of forage plants. Resource-management plans to improve range ecological status and forage production must fully recognize that stone pavement on an area essentially determines how much the vegetation can be improved realistically. Costs to implement management plans should be weighed realistically against benefits that might be achieved.

Successful livestock ranching in Klamath Province in Oregon depends largely on irrigated pasture during part or all of the summer grazing period because of the lack of native summer range in the area. A few ranches have summer and early fall grazing in the forested area west of Klamath Falls and on several mountains. This general lack of native summer range at least partly explains why rangeland ecological status generally is quite low in the province. Historic pressure to turn out on the range as soon as possible in spring and to stay off irrigated fields until crops are harvested in autumn likely contributed to current ecological status.

Expansion of western juniper, which now covers virtually all noncultivated and nonforested areas in the province, is a major problem. Various methods of eradication have been tested; the main lesson learned is that eradicating junipers is not easy nor always cost-effective. However, some juniper control projects, coupled with grazing management systems, have improved ecological status and produced more and better livestock and wildlife forage.

One of the most important aspects of Klamath Province in Oregon is its excellent wildlife habitat. The wide variety of herbaceous and shrub species forms ideal habitat, especially for deer. Nearly all sites except in forested areas produce significant amounts of bitterbrush, which is a prime winter-range browse for deer. Normal use for big game should be considered when managing livestock and other uses of the area.


Province Demarcation

Klamath and High Desert Demarcation

The line of demarcation between Klamath and High Desert provinces begins at the Oregon–California border at about 6,000 feet elevation south of the dry Big Lake, which is southwest of Adel in Lake County. The line meanders north at about that elevation to cross Parsnip Creek west of Adel, up Drake Creek to cross the Plush cutoff road east of Drake Peak and on northward across Twelvemile and McDowell creeks. At Honey Creek, the line veers west, to the south end of Abert Rim, then south to Sherman Valley. From there it follows north along the west side of Abert Rim escarpment nearly to Lake Abert. Then it turns southwest to the vicinity of Valley Falls, which is in High Desert Province. From the vicinity of Valley Falls, the line travels northwesterly at about 4,500 feet elevation along the western boundary of Chewaucan Valley, around Tucker Hill, south up Moss Creek about 6 miles, then northwest along the valley at the base of Winter Ridge. The communities of Paisley and Summer Lake are in High Desert Province.

About 3 miles north of the community of Summer Lake, the line goes west along the headwaters of various drainages that drain north into Silver Lake basin. It continues west about 5 miles south of Silver Lake community into the headwaters of Bridge Creek. At this location, Klamath, High Desert, and Mazama provinces join.

The line of demarcation between Klamath and High Desert provinces is based on soil lines between Booth–Bluejoint and Woodcock–Mound soil associations, which typify Klamath Province, and the Floke–Olson, Harriman–Hager, Crump–Ozamis, and Hart–Plush soil associations which typify High Desert Province.84

Klamath and Mazama Demarcation

The line of demarcation between Klamath and Mazama provinces runs south to the west of Thompson Reservoir, which is in Klamath Province, then around Sycan Butte, which is in Mazama Province, and along the east side of Sycan Marsh, also in Mazama Province.76 From about 5 miles southwest of Sycan Marsh on the Sycan River, the line heads east and runs northeast across the headwaters of Sycan River and then southeast in the vicinity of Winter Rim. From the south portion of Winter Rim, the line travels south across upper Elder Creek to west of Campbell Lake and south of Deadhorse Rim where it veers west along the south-facing slopes of Gearhart Mountain, which is in Mazama Province.84

From the area south of Gearhart Mountain, the line goes west to North Fork Sprague River. From there it snakes its way west more or less near the north boundary of Sprague River valley. Ferguson Mountain is in Mazama Province. From the vicinity of Knott Tableland, which is in Klamath Province, the line meanders northwest, passing about 5 miles north of Sprague River community which is in Klamath Province. From there, it runs south and west to the vicinity of Chiloquin and south to Lobert Junction.

From the vicinity of Lobert Junction on Highway 97, the line winds north along the east side of Agency Lake to the vicinity of Klamath Agency, which is in Mazama Province, then northwesterly to about 4 miles west of Fort Klamath along the east side of Klamath Point. Klamath, Mazama, and Cascade provinces join in the vicinity of Klamath Point.

The line of demarcation between Klamath and Mazama provinces is based on soil lines between Woodcock–Mound, Hart, and Lorella soil series, which typify Klamath Province, and Lapine, Shanahan, and Kirk–Chock soil series, which typify Mazama Province.84

Klamath and Cascade Demarcation

From the vicinity of Klamath Point, in Cascade Province, the line of demarcation between Klamath and Cascade provinces heads south at about 5,500 feet elevation along the east side of Klamath Point, Lather Mountain, Pelican Butte, Mt. Harriman, Buck Peak, and Buck Mountain. From Buck Mountain the line turns northwest at about 5,500 feet elevation around the headwaters of Jenny Creek to the area southwest of Brush Mountain, which is in Cascade Province. It is in this vicinity that Klamath, Cascade, and Siskiyou provinces join.

The line of demarcation between Klamath and Cascade provinces is not based on soil maps. Rather, the line represents the approximate boundary between the mixed- pine–mixed-fir forests of Klamath Province and the colder, more moist mixed-fir–hemlock forest, which typifies Cascade Province.50 However, in this area, the Dumont–Coyata and Donegan–Killet soil associations are associated with mixed fir–hemlock forest of Cascade Province; Pokegema–Woodcock soil association is associated with the mixed-pine–mixed-fir forests of Klamath Province.61

It is possible that more intensive soil investigations might reveal distinguishable differences at the soil series level between the mixed-fir–hemlock forest of Cascade Province and the mixed-pine–mixed-fir forest of Klamath Province in the vicinity of this portion of the demarcation line.

Klamath and Siskiyou Demarcation

From the juncture of Klamath, Cascade, and Siskiyou provinces southwest of Brush Mountain in eastern Jackson County, the line of demarcation between Klamath and Siskiyou provinces follows southward near Grizzly Creek and then down Jenny Creek to cross Highway 66 near Pinehurst. From the vicinity of Pinehurst, the line runs easterly to south of Parker Mountain and to the Klamath River where the line veers south to the California state line.

The line is not based on soil maps. Rather, it is the approximate boundary between the area vegetated with juniper, oak, and wedgeleaf ceanothus plant communities, which typify Siskiyou Province in this area, and the mixed-pine–mixed-fir plant communities, which typify the Klamath Province.50 However, the Pokegema–Woodcock soil association is associated with the mixed-pine–mixed-fir forests of Klamath Province in this area and the Skookum–McMullin and McNull–McMullin soil associations are associated with plant communities including juniper, oak, pine, and wedgeleaf ceanothus in this area, which typify Siskiyou Province. Wedgeleaf ceanothus is a key ecological indicator species on arid sites in Siskiyou Province.