Gather tools that will help you acquire a sample
- Cutters, small shovel, hand lens, plastic bags, marker, etc.
Go to the field with an open mind and investigate all possibilities!
- Look at the big picture first, then the details

Know the crop you are working with

What does the crop normally look like
- Is it appropriate for this stage in the planting
How does your crop compare

Recall important dates/events

Planting date
Any chemical applications
Weather conditions
- Throughout the planting
- During critical events
When problem appeared
- Gradual or sudden
Soil history
- Previous crop

Assess the site for symptoms

Single plant/entire planting
Only certain varieties
Wet/dry area
Sun/shade
Scattered
Pattern
- Specific row(s)/edge of field/circular spots

Determine where problem is found on the plant(s)

Old growth/new growth
Bottom/top of plant
Whole plant/one side
Scattered

Identify parts of the plant that are affected

Use a hand lens to closely inspect for insects or spores (underside of leaves)

Leaves
Branches/twigs
Stem/stalk/trunk
Flowers/fruits/seeds
Seedlings
Roots
Whole plant

Observe Symptoms

Wilting
Yellowing/browning
Distortion/curling
Leaf spots
Stunting

Take a Sample

Include moderate symptoms or margin between healthy and affected
Fill out: Diagnostic form
Submit to County Cooperative Extension Office

Authors:

Nancy F. Gregory, Plant Diagnostician

Jen Rushton, Intern

Date: 8/16/2018

Revision Date: February 2025

Download/Print PDF Version

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