Ecological Land Types within LTA 6.

ELT 6a

Elevation Range
Minimum: 
801 m
Minimum in ft: 
2627 ft
Maximum: 
891 m
Maximum in ft: 
2924 ft
Median: 
841 m
Median in ft: 
2759 ft
Soil Summary: 
very deep, gravelly sandy loam surface layers over gravelly sandy loam and gravelly sandy clay loam subsurface layers, other soils associated with recent alluvium have sandy loam surfaces over fine sandy loams, sandy loams and very gravelly sandy loams; depth to lime ranges from the surface to more than a foot below the surface; weak to moderate (clay accumulation) development; dominated by Pima County soil survey map units 54 (Palos Verdes-Jaynes complex, 2 to 8 percent slopes) and 3 (Anthony fine sandy loam, 0 to 3 percent slopes). These units comprise 85 and 8% of the ELT, respectively
Geologic Materials: 
alluvium and residuum associated with middle to late Pleistocene piedmont alluvium, undivided (Qi), late to latest Pleistocene piedmont alluvium (Qi3), Pantano Formation (Tp), Holocene river deposits (Qy2, Qyr), and small areas of rock exposure (mostly granodiorite) which comprise 70%, 9%, 11%, 7% and 3% of the unit, respectively
Landforms: 
finely dissected, weakly to moderately incised fan and pediment surfaces

ELT 6b

Elevation Range
Minimum: 
817 m
Minimum in ft: 
2682 ft
Maximum: 
934 m
Maximum in ft: 
3063 ft
Median: 
844 m
Median in ft: 
2769 ft
Soil Summary: 
shallow to granitic rocks and very deep, gravelly and very gravelly sandy loam surface layers over gravelly sandy loam and gravelly sandy clay loam subsurface layers, other very deep soils derived from recent alluvium have very gravelly fine sand surface layers and extremely gravelly sand subsurface layers; lime depth ranges from the soil surface to more than a foot below the surface; the shallow soils derived from granite have no lime; weak to moderate (clay accumulation) development; dominated by Pima County soil survey map units 54 (Palos Verdes-Jaynes complex, 2 to 8 percent slopes), 16 (Chimenea very gravelly fine sandy loam, 5 to 15 percent slopes), and 5 (Arizo-Riverwash complex, 0 to 3 percent slopes). These units comprise 56,19 and 13% of the ELT, respectively
Geologic Materials: 
alluvium and residuum associated with middle to late Pleistocene piedmont alluvium, undivided (Qi), late to latest Pleistocene piedmont alluvium (Qi3), small areas of rock exposure (mostly granodiorite, Xrv), Pantano Formation (Tp), and Holocene river deposits (Qy2, Qyr) which comprise 49%, 19%, 16%, 9% and 6% of the unit, respectively
Landforms: 
finely dissected, weakly to moderately incised fan and pediment surfaces

ELT 6c

Elevation Range
Minimum: 
815 m
Minimum in ft: 
2674 ft
Maximum: 
843 m
Maximum in ft: 
2766 ft
Median: 
826 m
Median in ft: 
2710 ft
Soil Summary: 
very deep; gravelly sandy loam and very gravelly fine sandy loam surface layers over gravelly sandy loam, gravelly sandy clay loam, fine sandy loam, and loam subsurface layers; lime depth ranges from the surface to more than a foot below the surface; weak to moderate development (clay accumulation); dominated by Pima County soil survey map units 55 (Palos Verdes-Sahuarita complex, 2 to 8 percent slopes) and 54 (Palos Verdes-Jaynes complex, 2 to 8 percent slopes). These units comprise 73 and 26% of the ELT, respectively
Geologic Materials: 
alluvium and residuum associated with middle to late Pleistocene piedmont alluvium, undivided (Qi) and Holocene river deposits (Qyr) which comprise 93% and 5% of the unit, respectively
Landforms: 
moderately dissected, weakly to moderately incised fan and pediment surfaces

ELT 6d

Elevation Range
Minimum: 
823 m
Minimum in ft: 
2701 ft
Maximum: 
839 m
Maximum in ft: 
2751 ft
Median: 
831 m
Median in ft: 
2726 ft
Soil Summary: 
very deep; gravelly sandy loam and very gravelly fine sandy loam surface layers over gravelly sandy loam, gravelly sandy clay loam, fine sandy loam, and loam subsurface layers; lime depth ranges from the surface to more than a foot below the surface; moderate development (clay accumulation); dominated by Pima County soil survey map unit 55 (Palos Verdes-Sahuarita complex, 2 to 8 percent slopes). This unit comprises 97% of the ELT
Geologic Materials: 
alluvium and residuum associated with middle to late Pleistocene piedmont alluvium and small areas of rock exposure (mostly granodiorite) which comprise 92% and 8% of the unit, respectively
Landforms: 
moderately dissected, weakly to moderately incised fan and pediment surfaces