Measurements

Area: Common metrics used in cotton production:

1 acre 0.4047 hectare  
1 feddan 1.038 acres 0.42 hectares
1 hectare 2.471 acres  
1 manzana 1.72 acres 0.696 hectares
1 sq metre 1.19603 sq yards  
1 strmma 0.1 hectare  
15 mu 1 hectare  

Bale: Is a package of compressed cotton lint after ginning, tied with wire or metal bands and wrapped in cotton, jute or polypropylene. Bales vary in weight in different countries but the universal density bale weighs 218 to 225 kg, has a density of 448 kg/m3 and measures nominally 1.400 X 0.53 X 0.69 m. A ‘bale’ is a basic tradable unit of lint (ginned cotton). Bale weights vary from country to country. By convention, a ‘statistical’ bale weighs 480 lbs. One American bale is 400-500 pounds (0.218 mt). In India, a bale euals 170 kgs of lint.

Classification: Cotton fiber is classified in four ways, by its length, micronaire, strength and uniformity.

Crop Year: Begins on August 1st of a given year and ends July 31st of the following year. All production which is harvested in that time period is counted in the crop year.

Fiber staple length categories: Cotton fibers may be classified roughly into three large groups, based on staple length (average length of the fibers making up a sample or bale of cotton) and appearance.

Short staple - includes the coarser cottons, ranging from about 10 to 25 mm in length, used to make carpets and blankets, coarse and inexpensive fabrics, and blends with other fibers.

Medium staple - contains the standard medium-staple cotton, such as American Upland, with staple length from about 25 to 30 mm.

Long and Extra Long staple - includes the fine, lustrous fibers with staple length ranging from about 30 to 65 mm and includes types of the highest quality—such as Sea Island, Egyptian, and pima cottons. Least plentiful and more difficult to grow, long-staple cottons are used mainly for fine fabrics, yarns, and hosiery.

Ginning Efficiency/Ginning Out Turn: A conversion factor used to convert seed cotton production to fiber/lint. Efficiencies range from approximately 20 percent (low) to 45 percent (high), with an average efficiency of approximately 33 percent.

Metric Ton (mt): Is the internationally recognised measurement for weighting cotton. A metric ton (mt) is 1000kgs (2205 pounds). 

Micronaire: The size of an individual cotton fiber taken in cross-section. Usually the Micronaire value is referred to evaluate fineness of cotton and its suitability for spinning particular count of yarn.

Quintal: In India, France and the former Soviet Union, the quintal is equivalent to 100 kilogram.  In Peru 1 quintal = 46 kg. In Spain, the metric quintal is also defined as 100 kg. In Portugal a quintal is about 58.75 kg. The German Zentner is pound-based, and thus since metrification is defined as 50 kg, whereas the Austrian and Swiss Zentner since metrification is 100 kg.

Yield: In most countries where cotton is produced, the output or yield is measured in terms of the weight of the seed cotton or raw cotton and includes the weight of the lint or fibre and that of the seed, unless otherwise mentioned as lint in countries where on-farm ginning is done.

Yield estimation is arrived at by many methods such as through dynamic simulation models (Penning de Vries et al. 1993; Aggarwal et al. 1995, Bhatia et al. 2006, Murty et al. 2007). In ideal conditions breeders can simulate optimal yields that might get reduced in on-farm conditions. A popular method still widely adopted is through arriving at a product of three factors such as plants per hectare, number of bolls per plant, and the weight of the bolls.

A Yield Gap is the difference between an expected and actual yield on account of various reasons such as soil management, weather conditions or pests and disease.  Final reporting of yield is done in Metric Tonnes of lint per hectare in confirmation with international reporting standards.

Further measurements and conversions: www.cotlook.com/index.php?action=conversion_factors 

and http://agropedia.iitk.ac.in/?q=content/glossary-useful-terms-related-cotton