1. Module 1 Field History Preparing for field assessment
Determine your survey approach
Extension agent Wayne Cooley, ARS agronomist Randy Anderson, and farmer Gilbert Lindstrom
Photo by Scott Bauer

2. Field History Ask questions! Get records, if possible
Make general observations
Learn to detect what might be causing the problem

3. Field History Previous crop Chemical history Planting date
Variety and seed lot
Tillage methods
Soil amendments
Weather
Movement of soil into field

4. Preparation for Field Assessment
Successful diagnosis starts with good preparation
Keep some useful tools around, and think about the history (as you know it) and nature of the concern

5. Preparation for Field Assessment
Notepad, record-keeping form or hand-held computers
Proper clothing, for safety
Always observe appropriate re-entry intervals (REI)

6. Preparation for Field Assessment
Hand lenses magnify tiny features that may be useful
Common magnifications 4X
10X
16X
20X

7. Aphid Magnification
English grain aphid

8. Rust magnification example
Barley rust photo: Vernyl Pederson

9. Preparation for Field Assessment Other useful tools
Trowel
Knife
Plastic baggies
Vial – with alcohol for insects
Camera – digital/35 mm
Bucket
Sweep net

10. Determine Survey Approach
Surveying (or scouting) requires consideration of approach or pattern of travel
Specific concerns may dictate a certain type of scouting method
Regardless of method – the goal is to get a representative sample

11. Determine Survey Approach
Scouting routes may be modified by:
topography
soil types
irrigation channeling
field entrances
Regardless of the approach, the goal is to get a representative idea of the problems

12. Determine Survey Approach
Scouting in a W or Z pattern for pests or problems distributed uniformly over the field
Examples: Foliar diseases later in season; European corn borer; Pesticide damage

13. Determine Survey Approach
Scouting or sampling in areas where pests or damage may be concentrated
Examples:
root rots associated
with low areas or
in patches;
cutworms in low,
cool areas;
white grubs

14. Determine Survey Approach
Pests or damage associated with field borders or waterways
Examples: grasshoppers, chinch bug

15. Determine Survey Approach
Number of sites to visit in the field
Sampling or surveying usually is done at 5 sites per 40 to 50 acres