Alfalfa and Clovers
When to sample – Just prior to bloom or harvest, whichever comes first. Earlier sampling is suggested only if a problem occurs.
What part of plant – For a sample taken just prior to harvest, or bloom, take the top 6 inches of plant. Samples taken earlier should include the top third of the plant.
How to sample – Collect material from 40 to 60 randomly selected plants in the problem area or field. If the stand is a mixture of legumes, separate by species and submit as separate samples.
Cotton
When to sample – Collect cotton leaf petioles from first square to mid-bloom growth stages.
What part of plant – Take the fourth leaf petiole from the top of the plant.
How to sample – Collect the most recently matured leaves from 35 to 50 plants selected at random in problem area or field.
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