Key points are not available for this paper at this time.
Abstract A procedure for obtaining iron which is both convenient and reliable is described. The procedure involves shaking the samples overnight in a citrate‐dithionite buffer. This is followed by a colorimetric iron determination using orthophenanthroline. The use of an automatic pipette, a flocculating agent, and noncritical quantities of dry reagents facilitates the determination. The results show increased effectiveness and reliability over Kilmer's porcedure for high‐iron Oxisols and Ultisols from Puerto Rico.
George G. S. Holmgren (Wed,) studied this question.