Field Mapping Order 3 Basic Soil Survey Training Lincoln, Nebraska

1. Field Mapping Order 3Basic Soil Survey TrainingLincoln, Nebraska

2. Rationale • Initial Soil Surveys in much of the Western US are conducted at the Order 3 level • Whether in Update or Initial soil survey, you need to understand how these surveys are made

3. Objectives • At the end of this module the learner will be able to: • Use existing data to “pre-map” an area for Order 3 mapping • Develop provisional map units for the pre-map • Develop a soil/landscape model • Take the generated pre-map to the field to test the model • Review documentation, refine the pre-map, and adjust the model

4. What is “Pre-mapping”? • Process for developing provisional map units (groups of similar delineations) • Based on availability of digital map layers • Can be done with hardcopy analog maps • Use what you have

5. Pre-mapping • Partition the landscape by • Landscape • Landform • Geology • Climatic patterns • Slope/aspect • Vegetative patterns • Others • Delineate and label areas of similar features • Define the soil-landscape model

6. Pre-mapping Example Photo Order 3 1:30,000

7. Landforms Order 3 1:30,000 Pre-mapping Example 1 2 3 1

8. Pre-mapping Example Geology Order 3 1:30,000 21 1 1 12 3 2 1 12 12

9. Aspect Order 3 1:30,000 Pre-mapping Example 3 13 21 31 1 1 12 3 13 2 1 13 12 12 13 1 1

10. Slope Order 3 1:30,000 Pre-mapping Example 22 3 13 21 1 31 14 1 14 1 14 12 22 32 3 14 13 1 2 13 12 12 14 13 1 1

11. Photo Signature Order 3 1:30,000 Pre-mapping Example 22 3 1 13 21 31 14 15 1 14 1 14 12 22 32 3 14 13 1 2 13 12 12 14 13 1 1 15

12. Provisional Legend • Ridges, mountain slopes, and drainageways-rhyolite, sandstone, and limestone-0 to 15 percent slopes • Ridges-sandstone-15 to 60 percent slopes 3 Highly dissected mountain slopes-colluvium from fanglomerate-15 to 60 percent slopes • Ridges, mountain slopes, and drainageways-marine sediments-15 to 60 percent slopes • Ridges, mountain slopes, and drainageways-rhyolite, sandstone, and limestone-udic-0 to 15 percent slopes • Ridges, mountain slopes, and drainageways-rhyolite, sandstone, and limestone-15 to 60 percent slopes • Ridges, mountain slopes, and drainageways-rhyolite, sandstone, and limestone-0 to 15 percent slopes-range • Ridges-marine sediments-0 to 15 percent slopes • Ridges-sandstone-0 to 15 percent slopes • Highly dissected mountain slopes-colluvium from fanglomerate-udic-15 to 60 percent slopes • Highly dissected mountain slopes-colluvium from fanglomerate-0 to 15 percent slopes

13. Provisional Legend • Every map unit that is tentatively identified is evaluated by these questions: • Does it capture the characteristic signature in the landscape that can be recognized from remote sensing imagery or field observation? • Is the unit recognizable and repeatable by other soil scientists? • Is it needed to meet the objectives of the survey?

14. Soil-Landscape Model Example

15. Develop a Mapping Plan • How many delineations will be visited? • How many notes will be gathered? • What kind of notes will be gathered? • Which delineations will be visited?

16. Site Visits Order 3 1:30,000 Choose Sites to Visit in Field 22 3 1 13 21 31 14 15 1 14 1 14 12 22 32 3 14 13 1 2 13 12 12 14 13 1 1 15

17. To the Field – But not to Dig! • Reconnaissance , drive the map if possible. Take photos when you can and document your points. • Ground-truth the accuracy of your data layers, slope, vegetation, geology and refine the pre-map as needed • Get the big picture before you get lost in a hole. Walk or hike the area without a shovel (gasp) • Return to the office and refine your mapping plan

18. Now Dig!!!