1. Soil Horizons By: Michelle K Jimenez

2. What is a Soil Horizon?!? • Different layers of soil. • There are five soil horizons. • The five soil horizons are called Master Horizons. • Each Master Horizons are distinguished by different colors, compositions, and characteristics. • The more layers soil has, the older it is!

3. Master Horizons • O • A • E • B • C Master horizons each have distinctive characteristics that distinguish one from another. Master horizons are always written with a capital letter.

4. Soilsensor.com

5. A Horizon: O Horizon: O horizon • Made up of organic material • A horizon is the mineral horizon • Dark in color, which is caused by a build up of organic matter. • Majority of soils have an A horizon

6. B Horizon E Horizon • Between the A and B horizon • In this horizon, a slow removal of fine clay and organic material is moved down through the soil. • Usually is found below A and B • In this horizon, an accumulation of clay, iron, and other materials are built up here.

7. C Horizon • Called the “Parent Material” from which A, E, and B horizons can develop from. Soilweb.com

8. Review C Match the letter to the horizon… O E B A http://www.uvm.edu/place/analyze/soil_horizons.html

9. Common Subordinate Horizons • p, g, k, and t • Always written with a lower case letter Ex: Ap or Bk

10. Subordinate Horizon: • p – horizon has been plowed or mixed, only goes with the A horizon • k- accumulation of carbonates Associated with the B horizon Found in an arid environment Contains high pH

11. Subordinate Horizons continued… • g- horizon has been water-logged Only goes with the B or C horizons Poor drainage • t- found in a temperate climate Accumulation of clay Found in the B horizon layer

12. Match the letters… t p A k B C g

13. A B C Pulling it all together…. • Which soil has been farmed? Why? • Which soil has the highest pH? Why? • Which soil is the youngest? Why? • Which soil(s) can be found in a temperate climate? Why? A A Ap E Bg Bt Bt Btk Cg Cr Ck