Module 1

Field HistoryPreparing for field assessmentDetermine your survey approach

Photo by Scott Bauer

Extension agent Wayne Cooley, ARS agronomist Randy Anderson, and farmer Gilbert Lindstrom

Field History

• Ask questions!• Get records, if possible• Make general observations• Learn to detect what might

be causing the problem

Field History

• Previous crop• Chemical history• Planting date• Variety and seed lot• Tillage methods• Soil amendments• Weather• Movement of soil into

field

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

NDSU Extension specialists trained IPM survey scouts in late May

New tools of the survey: Portable computers and Global positioning units.

NDSU Extension specialists trained IPM survey scouts in late May

New tools of the survey: Portable computers and Global positioning units.

Preparation for Field Assessment

• Notepad, record-keeping form or hand-held computers

• Proper clothing, for safety

• Always observe appropriate re-entry intervals (REI)

Preparation for Field Assessment

• Hand lenses magnify tiny features that may be useful

• Common magnifications– 4X– 10X– 16X– 20X

Aphid Magnification

English grain aphid

Rust magnification example

Barley rust photo: Vernyl Pederson

Preparation for Field Assessment Other useful tools

• Trowel• Knife• Plastic baggies• Vial – with alcohol for

insects• Camera – digital/35 mm • Bucket• Sweep net

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

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

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

Determine Survey Approach• Scouting or sampling in

areas where pests or damage may be concentrated

Examples:root rots associated with low areas orin patches;cutworms in low, cool areas;white grubs

Determine Survey Approach

Examples: grasshoppers, chinch bug

Pests or damage associated with field borders or waterways

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