‘Productivity’ variation in the Mulgrave district from 1902 to 2018

The paper discusses variation in Mulgrave district productivity in terms of cane yield (t cane/ha), CCS, and CCS yield (t CCS/ha). After years of overall steady increase from the 1940s, cane yield reduced from 1999 and the frequency of low productivity years increased significantly. A relative-terms measure of performance against 10-year centred moving averages indicated that volatility in results decreased from early 1950s but increased again from the 1980s. There had been a steady decline in CCS as cane yield increased. Significantly lower CCS occurred in the 1990s, before an overall increase following the introduction of a cane-quality scheme in 2001. Relative-terms assessment indicated an increase in CCS volatility since the 1980s. CCS yield increased from the 1940s to a peak in the 1970s and into the early 1990s, before declining to a new plateau equivalent to around 1960 levels. Relative-terms assessment found reduced volatility from the later 1950s, broken by three especially low productivity years since 1999. Weather was examined a driver of productivity outcomes. While correlations were found, the spread of results indicated other factors were making considerable contributions. The impact that productivity changes have had on grower potential to generate income was examined by normalising for sugar price ($400/t) and harvest cost ($8/t). This showed that the potential for normalised after harvest- cost grower revenue (NAHCGR) returned peak 10-year averages from 1969–78 ($2,398/ha) and 1983–92 ($2,396/ha) but suffered an overall drop from the later 1980s. The average from 1970–85 was $2,371, compared to $2,067/ha from 1997–2018. In addition to a reduction in NAHCGR of over $300/ha, this latter period also showed considerable volatility that potentially complicated grower financial management. Analysis of the relationship between CCS yield and NAHCGR found a shift. For a given CCS yield, NAHCGR reduced by an average of around $130/ha following the adoption of green-cane harvesting. Significant shifts in farming practices have lowered input costs, but also appear to be delivering a lower after harvest-cost revenue potential. Stakeholders have cited factors such as weather, pest damage, growing and harvesting practices, season length, and varieties for productivity issues. However, explanations and solutions are unlikely to be found through considering individual factors in isolation, and a more holistic view would be beneficial. Key words Mulgrave district, farm productivity, normalised grower returns