I.
Azonal, ecological sites defined by hydrology rather than soil properties (ie riparian) (LRUX)
A.
Soils in a thermic temperature regime
1.
Site receives surface water flow or has a water table associated with stream hydrology
i.
Site occurs along perennial streams and rivers
ii.
Site associated with ephemeral streams or drainages - R018XX999CA
2.
Site not as above
i.
Site occurs on concave landscape positions- dominated by Juncus, Carex and forbs - follow key for LRU I
ii.
Site not as above
a.
Site occurs in a meadow or near a stream riparian complex- but on soils which support upland plant species- Valley oak common in overstory - follow key for LRU I
b.
Site not as above, may be another type of wetland not associated with streams - R018XX999CA
B.
Soils in a mesic temperature regime
1.
Site occurs in alluvial floodplains, but vegetation is more upland: oaks, Valley oak dominates the site - LRU 22AI
2.
Site is clearly riparian. - LRU 22AX
II.
Not as above,
A.
Geology consists of young (Tertiary) volcanic flows originating in Southern Cascades (north & west of Lake Oroville) (LRU A)
1.
Soil temperature regime thermic
i.
Riparian systems (lentic, lotic, floodplains, etc.) - R018XX999CA
ii.
Site not as above, primarily bedrock controlled soils
b.
Site not as above
2)
Not as above
a)
Soils on volcanic ridges or rocky, undulating foothills
(2)
Soils not as above
(a)
Soil occurs on volcanic cone, in a mesic pocket (otherwise thermic dominated area) and with infrequent plant communities of knobcone pine/incense cedar/ ponderosa pine
... CX018XA203 – Mesic Volcano Cones
b)
Soils occur in concave landscape position on hills, or undulating plateaus with deep to very deep soils
2.
Soil temperature regime mesic
i.
Soil texture class medial or with an isotic mineralogy class (vegetation tends to be dominated by coniferous forest, including sugar pine, doulgas fir, knobcone pine) - F018XA203CA
ii.
Site not as above
B.
Geology older (generally Mesozoic Era) or mixed ages associated with Sierra Nevada (beginning around Lake Oroville)
1.
Geology is dominated by granitoid almost exclusively. Break between Valley (MLRA 17) and the foothills abrupt, with steep slopes occuring from the lowest foothills to the MLRA 18/22A break.
i.
Subhumid climate. Soil moisture regime is xeric and only aridic at the lowest elevations (usually in conjunction with the valley). (LRU C)
b.
Soil chemistry a lesser contributing factor
1)
Mean Annual Precipitation (MAP) < 23 "
a)
Soils have shrink-swell properties and clayey PSC
b)
Site not as above
(1)
Soils shallow depth class
2)
MAP ≥ 23
a)
MAP ≥ 30
(1)
Site occurs in shallow to moderately deep soils
(a)
Soils on granite and support dense chaparral - R018XC107CA
(b)
Soils on other parent materials
(1)
Soils are on marble, often on canyon walls, yucca-chamise associations are common - R018XC109CA
(2)
Site occurs in deep to very deep soils on concave positions
(a)
Site occurs in steep narrow drainages , often metamorphic PM, dominated by California buckeye and mesic chaparral shrubs (Mahogany, flannelbush) - R018XC110CA
(b)
Site occurs on broadly concave mountain slopes, generally in granite PM, closed canopy (interior/canyon live oak) and buckeye, often with California bay. - F018XC203CA
b)
MAP < 30 inches
(2)
Site ocurs on all aspects, generally on moderately deep to very deep soils. Vegetation consists of blue oak woodland and savannas - F018XC201CA
ii.
Semi-arid climate with interchanging soil moisture regimes (xeric & aridic). Moderately to steep hills & mountains at southern end of Great Central Valley.
a.
Mean elevation > 3,200 ft (soil temperature regime thermic to mesic). This LRU occurs at the crossroads of several MLRA's. Vegetation patterns reflect the confluence of desert (MLRA 29), mountains (MLRA 22A), and foothills (MLRA 18) vegetation, to include juniper/ blue oak woodlands, yucca and other species from adjacent regions. (MLRA 22AO)
b.
Mean elevation < 3,200 ft (Vegetation patterns conform to vegetation classes and ecosystem dynamics of other LRU's in MLRA 18 with annual grasslands/ blue oak savannahs being most common plant community.) (LRU E)
1)
Riparian (driven by hydrological features) - R018XX999CA
2)
Site is an upland
a)
Soil temperature regime is solidly thermic and landform is hills or terraces
(1)
Soils are calcareous and very deep, pH ranges into alkaline (> 8 pH) - R018XE101CA
(2)
Soils not as above
(a)
Soils have heavy texture or exhibit cracks with seasonal wetting-drying cycles - R018XE102CA
(b)
Site not as above
(1)
Soils are shallow (AWC 1-2 inches); vegetation is annual forbs/grasses with very few trees - R018XE103CA
(2)
Soils are moderately deep to deep (AWC 3-5 inches), often with mollic epipedons; vegetation includes oak woodland with dense annuals. - R018XE104CA
b)
Soil temperature regime is borderline mesic and landform is hills or mountains (buckeye, foothill pine, and interior live oak indicator species) - F018XE201CA
2.
Geology highly complex, interfingering of volcanic, sedimentary (metamorphozed), and some granitics. The break between MLRA 17 and MLRA 18 is more gradual than in the southern LRU's, lower foothill slopes gently to strongly sloping. (LRU I)
i.
Site occurs on ultramafic soils
b.
Site not as above
ii.
Site not as above
a.
Site occuring on lava plateaus or erosion remnants, and skirting the adjacent hillslopes
b.
Site occurs on a hill or hillslope (various geologies)
1)
Mean Annual Precipitation (MAP) is generally well below 18 inches
a)
Sites consist of ridges and or terraces or alluvial fan remnants
(1)
Sites occurring on shallow to moderately deep soils, sometimes rocky
2)
MAP is at least 18 inches
a)
MAP ≤ 25 inches
(2)
Site on upland, bedrock controlled
b)
MAP > 25 inches
(1)
Site is steep AND aspect dependent, generally occuring on north-facing slopes on lower elevations, and on reverse aspects (s-facing) as elevation increases
(b)
Site definitely thermic STR, ppt < 34
(2)
Not as above
(a)
Site in thermic soil temperature regime
(1)
PM intrusive igneous, excluding footslope and toeslope positions (depositional areas)
(a)
South to west-facing aspects, usually chamise dominated - R018XI106CA
(2)
Site not as above
(b)
Site not as above
(1)
Site dominated by volcanic bedrock
(a)
Soil depth shallow (Inks, Pentz, Amador soils) annuals dominate the site, AWC 1-4 - R018XI107CA
(b)
Soil depth deep to deeper, oak woodland or savannah, AWC 3-7 - F018XI207CA
(2)
Site not as above
(b)
Soils are generally deeper, live oak dominated and dense overstory - F018XI202CA
(b)
Site in a mesic STR
(2)
Site occurs along edges of MLRA 22A break, mesic STR more common
(a)
Site generally shallow occuring on narrow ridges or sideslopes below prominent ridges, vegetation consists of annuals forbs and grasses and scattered shrubs/foohtill pine - R022AI101CA
(b)
Site not as above, slope gradient generally steep
(1)
Soils shallow to moderately deep (rarely deep) on S-facing slopes. Vegetation consists of chaparral shrubs - R018XI105CA
(2)
Soils generally deeper and occur on all aspects, PIPO-oak-shrubland - F022AI201CA