Soil great group
Paleustalf
Of the Ustalf suborder; it is very old and evolved: very thick clay horizon, or a petrocalcic horizon (calcareous hardpan) indicating a long time of formation.
What the name says
Soil Taxonomy names are built from parts, and each part says something about the soil. From general to specific:
| Taxonomic order | Alfisol | Soil with a clay accumulation horizon (argillic or natric) and good base saturation, but without the thick, dark surface of a Molisol. |
|---|---|---|
| Suborder | Ustalf | Alfisol from subhumid to semi-arid climate (ustic moisture regime). |
| Great group | Paleustalf | Within the Ustalf suborder, it is very old and evolved: very thick clay horizon, or a petrocalcic horizon (calcareous hardpan) indicating a long time of formation. |
What it means for farming
Acceptable fertility, but the surface layer is thinner and poor in organic matter. In the Pampas region many Alfisoles are sodic or floodable (Natracualfes) and are left for livestock.
- Most common surface texture
- Clay loam
- Most common drainage
- Imperfect
- Typical effective depth
- 125 cm
Where it is found
According to the 1:500.000 national map, it covers about 44.135 ha, spread over 5 districts.
Loading map…
National map units that list it. The scale is 1:500.000: good for seeing the region, not a single property.
| Province | Area |
|---|---|
| Jujuy | 25.634 ha |
| Salta | 18.501 ha |
Districts where it is most common
Subgroups on the maps
The definitions are a plain-language summary of the USDA Keys to Soil Taxonomy. The formal definition includes thickness, color and percentage thresholds that are left out here.
Sources
- Soil Survey Staff. (2014). Claves para la Taxonomía de Suelos, 12.ª edición. USDA - Natural Resources Conservation Service. · Dominio público (USDA)
- INTA · Dominio público (carta 1:500.000)