The LCC is usually a plastic, ruler-shaped strip containing four or more panels that range in color from yellowish green to dark green. Several types of LCCs with varying shades of color have been developed and distributed to rice farmers. This created uncertainties regarding which LCC to use and led to requests for a standardized LCC that serves as a reference in cross calibrating threshold values among LCCs. In October 2003, the External Review Panel of the Irrigated Rice Research Consortium recommended “standardization of the LCC with harmonized color formula accompanied by calibration with local rice leaf characteristics and training of extension workers and farmers to use the LCC … as soon as possible”. IRRI in collaboration with the University of California Cooperative Extension soon afterwards released a standardized LCC with improved quality assurance for the reproducibility of colors and enhanced matching of the colors to the reflectance spectra of rice leaves (Witt et al. 2005). The standardized LCC (photo above) is five inches long, made of high-quality plastic, consisting of four color shades from yellowish green (No. 2) to dark green (No. 5). The color strips are fabricated with veins resembling rice leaves. |
