1. Delineating Soil Horizons

2. Soil as a Natural Body Parent Material Bedrock Additions Losses Translocations Transformations Differentiation Bedrock

3. Soil Horizons Roughly parallel layers in the soil with varying composition and properties

4. Master Horizons

5. Criteria for Characterizing Soil Horizons ColorTextureDensityStructure Organic matter MineralogyChemistry

6. Soil Color

7. Mineralogy of the soil/parent material Relative amount of organic matter Hydrology of the soil Soil chemistry Soil Microbes Soil Color Determinants

8. Coloring Agents in Soils Organic Matter Grey to Black coloration particularly in topsoil or A horizon material. Can be found in the sub-soil as an accumulation Elements and Compounds Iron, manganese Reddish to yellow-brown Purplish black

9. Soil Color Determination

10. Value Chroma Hue Munsell Soil Color dominant spectral color; related to the wavelength of light. Related to the proportions of red to yellow. In soils we only use 1/5 of the color chips available. related to total amount of light reflected. measure of the strength of spectral color

11. 0 2.5YR 5YR 7.5YR 10YR 0 2.5 Y 5Y 10R

12. Hue 10 R 2.5 YR 5 YR 7.5 YR 10 YR 2.5 Y 5 Y RedYellow Increasingly dominated by yellow spectral color Pages Florida soils dominated by 7.5 YR and 10 YR pages

15. Soil Color

16. Hue = 10 YR Value = 6 Chroma = 3 Munsell Color 10 YR 6/3

17. 10 YR 2/1 10 YR 5/6

18. Pale Red Red Weak Red light Red Pink Dark Red

19. Summary A horizon – mid/low value - low chroma E horizon – high value - low chroma B horizon – ? value - ? chroma

20. Water table depth Oxygen status Development decisions

21. Hue 10YR or Yellower Value≤ 3 Chroma ≤ 1 Hydric Soil Classification “Black Histic”

22. MineralFormulaSizeMunsellColor goethiteFeOOH(1-2 m m)10YR 8/6yellow goethiteFeOOH(~0.2 m m)7.5YR 5/6strong brown hematiteFe 2 O 3 (~0.4 m m)5R 3/6red hematiteFe 2 O 3 (~0.1 m m)10R 4/8red lepidocrociteFeOOH(~0.5 m m)5YR 6/8reddish-yellow lepidocrociteFeOOH(~0.1 m m)2.5YR 4/6red ferrihydriteFe (OH) 3 2.5YR 3/6dark red glauconiteK(Si x Al 4- x )(Al,Fe,Mg)O 10 (OH) 2 5Y 5/1dark gray iron sulfideFeS 10YR 2/1black pyriteFeS 2 10YR 2/1black (metallic) jarositeK Fe 3 (OH) 6 (SO 4 ) 2 5Y 6/4pale yellow todorokiteMnO 4 10YR 2/1black humus 10YR 2/1black calciteCaCO 3 10YR 8/1white dolomiteCaMg (CO 3 ) 2 10YR 8/2white gypsumCaSO 4× 2H 2 O 10YR 8/3very pale brown quartzSiO 2 10YR 6/1light gray

23. Low Value Low Chroma Low Value high Chroma High Value

25. Criteria for Characterizing Horizons ColorTextureDensityStructure Organic matter MineralogyChemistry

26. Jon Demps Melissa Odal Grant Baysinger Daniel Kristiansen Markihe Anderson Percy Harvin See the Teaching Assistants Before Leaving: Also anyone who has not received a student number