Timing of defoliation is critical to insure optimum yield and fiber quality. The use of micronaire testing to determine the optimum time to defoliate can reduce the risk of penalties from high or low micronaire.

Developed by well known cotton researcher, Hal Lewis, this program can accurately predict the micronaire level at various percentage of open bolls. A high micronaire level for example would indicate the need to defoliate early to avoid a penalty for high micronaire, while a low level would indicate the need to wait. The ideal levels are considered to be between 3.8 and 4.5. This information will aide you in determining the optimum time to defoliate and assist in scheduling.

The textile industry is demanding better quality cotton, and growers need information as soon as possible on the trade-off between yields and price.

The July USDA Daily Spot Cotton Quotations showed discounts as high as 12.5 cent a pound for low micronaire. Micronaire testing along with boll counts and other estimates of maturity such as slicing green bolls can improve quality and yields and help avoid discounts.

Sample at least 4 areas which are representative of the field. Hand pick all the open 1st position bolls from the 1st, 4 fruiting branches. Seed cotton should be open, fluffed and dry when picked and the seed should crack. Sample at least 8 plants from each area. Place the sample in a clean paper bag and label. The more thoroughly the field is sampled the more accurate the results. If bottom fruit has dropped do not sample above the 1st 4 branches. Sample additional plants to obtain at least 32 bolls. Sampling bolls from above the 1st 4 fruiting branches will give unreliable results.