Suborders of Ultisols

1. Suborders of Ultisols Aquults Humults Udults Ustults Xerults

2. Aquults • water table at or near the surface for most of the year. • Redoximorphic features found in all layers below 25 cm. • Found in; South East United States along the Atlantic Sea board, South East Asia which includes Indonesia, Malaysia and the Philippines, Upper Amazon River Basin, Congo/Zaire River Basin of Central Africa, and other humid tropic regions with acidic parent materials. • This suborder of the Ultisols can most likely be found in the inter floodplain.

3. Humults • High organic carbon content • Well drained soil, not as wet as Aquults • U.S. found in Willamette Valley of Oregon and into Washington

4. Udults • Found in humid climates • Short periods of dry season • Slightly lower organic content than Humults • Cover vast majority of South Eastern U.S.

5. Ustults • Limited moisture • Soil moisture/ availability is seasonally adequate for at least one crop a year • Found in semiarid and sub humid climates

6. Xerults • Temperate Ultisol • Extreme dry summers with moist winters • Sacramento Valley

7. Suborders of Oxisols • Aquox • Torrox • Ustox • Perox • Udox

8. Aquox • Water table at or near the surface for most of the year • wet Oxisols in shallow depressions and in seepage areas at the base of slopes • A histic epipedon with a hue of 2.5Y or yellower • Found in North Central South America, Central Africa, Countries close to Equator Globally. • redox concentrations within 50 cm of the mineral soil surface

9. Aquox Locations

10. Torrox • These are Oxisols of arid regions • known to occur only Hawaii in the United States

11. Ustox • Found in semiarid and subhumid climate • Ustox may be the most extensive suborder, occurring over a large portion of the interior of South America and in extensive areas of Africa.

12. Perox • well drained Oxisols • Found in humid climates where precipitation exceeds evapotranspiration all year • Poor quality for crops • “Low activity Soils”

13. Udox • Found in humid climates • well drained Oxisols • natural rainfall in normal years is abundant and are areas are dry in some parts for less than 90 days,

14. Vertisols • Aquerts • Cryerts • Xererts • Torrerts • Usterts • Uderts

15. Aquerts • These soils are typically in low areas, such as glacial lake plains, flood plains, stream terraces, and depressions. • water table at or near the surface for most of the year • Manganese oxide gives it dark color • Rice production in Sacramento Valley of California in winter months

16. Cryerts • Cold climates • Usually found at grassland/ forest grassland transition zones of Canadian praires and possibly in Russia • Fine textured • periodically shrink and swell, Cracks commonly open once a year, late in the summer.

17. Xererts • Vertisols of Mediterranean climates, which are typified by cool, wet winters and warm, dry summers • damage to structures and roads is very significant • Cracks open for atleast 60 consecutive days in both summer and winter seasons

18. Torrerts • arid climates • Found in small quantities in Texas, New Mexico and Arizona, but is the most extensive suborder found in Austrailia. • closed depressions that can hold ponds from time to time by runoff from the higher areas. • parent material basalt.

19. Usderts • Texas, Australia, Africa, and India • cracks in normal rainfall years are 5 mm or more wide • Low rainfall during the summer, tropical and subtropical areas that have two rainy and two dry seasons • derived from basic igneous rocks

20. Uderts • humid areas • gentle slopes and are derived dominantly from marine shales and alluvium • At one time many of these soils supported grass, although some support a hardwood or pine forest

21. Aridisols • Cryids • Salids • Durids • Gypsids • Argids • Calcids • Cambids

22. Cryids • cold desert soils • high elevations, dominantly in the mountain and basin areas in the United States and Asia

23. Salids

24. Salids • common in depressions in the • Upper boundary within 100 cm of soil surface • Occur where salts are concentrated near the surface, driven up wards by evaporation • sodium chloride • Salids are unsuitable for agricultural use

25. Durids • have a duripan that has an upper boundary within 100 cm of the soil surface, but most are within 50 cm of the soil surface • occur dominantly on gentle slopes-Range Land • soils commonly have calcium carbonate

26. Duripan

27. Gypsids • gypsic or petrogypsic horizon within 100 cm of the soil surface • Accumulation of gypsum takes place initially as crystal aggregates in the voids of the soils • gypsic horizon occurs as a cemented impermeable layer, • Gypsids occur in Iraq, Syria, Saudi Arabia, Iran, Somalia, West Asia

28. Gypsic Soil of Italy

29. Argids • do not have a duripan within 100 cm of the soil surface • high concentration of salts hinder clay illuviation

30. Calcids • Found on geologically younger slopes • calcium carbonate in parent materials • extensive in western United States other arid regions of the world.  • Do not have a duripan or a salic, gypsic layer within 100 cm of the soil surface

31. Cambids • Aridisols with lowest soil development • Weakly developed B horizon • most common Aridisols in the United States