Corn

According to Mr. Juste (INRA Agronomy Station Bordeaux) and Mr. Loue:

When to Sample: Never sample before flowering.

Where: It is advisable to sample separately from areas that may differ by factors such as: variety, density, sowing date, cultural practices, irrigation, soil type, and fertilization date.

How: The leaf below the main ear. Only retain the central third of the leaf, and remove the central vein on the spot.

Quantity:

• 12 leaves: from young plants (with 5 or fewer leaves).
• 20 leaves: from plants with at least 8 leaves.

Conditioning: Place the batch of leaves in a clean, sturdy plastic bag. Label each batch clearly with: Name, address, variety, date of sampling, and plot reference.

Precautions: Avoid contamination of the plant by soil. Send to the laboratory by express.