FIGURE 15.2 - Information regarding the nature of the library is written on the side of each X/I/C tray (writing on the bottom of trays can interfere with automated picking) using a marker with ethanol-soluble ink. For example, in the drawing above, the species name (S. bicolor = Sorghum bicolor), the cultivar (BTx623), and the date the library was made (September 1999) are written directly on the tray.