A POTASH SURVEY IN THE PIONEER MILL AREA

Summary The recurrently high ash problem in raw sugar manufactured from cane grown in the Burdekin area prompted an investigation into the source of the main consituent of raw sugar ash in this area-potassium. As a result, a survey was carried out embracing the sampling and analysis for potassium of approximately 200 samples of the four main varieties of cane grown in the district, together with the soil in which these samples were grown. Statistical analysis of the results has shown that there is little difference in juice potash levels among the canes sampled in respect to age and cane type. A strong relationship was found to exist between soil potash and potash in juice solids for all varieties. Variations in the weight extraction of juice had little influence on the quantity of potassium expressed with the juice on a variety and age comparison, except for Trojan plant cane, which was the only variety significantly affected. A similar trend existed in the comparison between cane maturity and potassium in juice, Trojan plant again being significantly affected. No relationship was apparent for the other varieties. The survey shows that there is a need to establish an optimum soil potash level in order to maintain sugar yields but allow reductions in the levels of potash in the cane juice, and thus reduce the amounts of ash entering the raw sugar process.