Once cotton bloom begins North Carolina growers have only a short time period during which they can identify and solve crop nutrient problems. In fact, the personnel at the plant Services Division point out that any problems must be fixed within "a few short weeks" of first bloom in order to be effective.
A plant tissue analysis is both a quick and inexpensive way to do this, notes NCDA&CS. An analysis measures nutrient levels within a crop for a $7 fee per sample and growers can find out in two business days whether their crop needs an application of fertilizer.
"Growers are urged to scout their fields and submit samples now," says N.C. Agriculture Commissioner Steve Troxler, "because after the fifth week of bloom, adding fertilizer will not provide any economic benefit."
NCDA&CS spokespersons note that growers should look for off-color or stunted growth when scouting their fields. Sandy areas, particularly, can lose nutrients due to leeching after heavy rains.
Cotton is susceptible to nematodes so it might pay to submit separate soil samples for nematode assay, as well. These are $3 per sample.
The NCDA&CS Agronomic Services Division notes comparative side-by-side samples taken and submitted from areas of good and poor growth can be helpful in diagnosing problems.
With results from plant tissue analysis and nematode diagnosis growers can learn answers to many questions they might have, including:
•Is there enough boron in the plant and should I make an additional application?
•Do I need to apply additional potassium?
•Are my plants pale or yellow due to a lack of nitrogen or sulfur?
•Did I apply enough sulfur this year? Is the nitrogen-to-sulfur ratio sufficient?
•Are nematodes a contributing factor to poor crop growth?
NCDA&CS notes regional agronomists can give growers advice on sampling technique, and sample submissions. They can also interpret reports and help growers determine the best way to follow recommendations. To identify the agronomist in your area, visit www.ncagr.gov/agronomi/rahome.htm, or call Kent Messick at 919-733-2655.
Additional information on collecting and submitting cotton tissue samples is available online at www.ncagr.gov/agronomi/uyrplant.htm.