Some varieties of cane are designed to be able to survive in drier soils without much rain and some are designed to take advantage of nutrient full volcanic soils. As sugar cane is a grass, it will grow again if cut. This requires the farmer to plant new cane. Cane planted the year before may be regarded as having age zero. The greatest age in this data is eigth ratoon, and it can be expected that the sugar content and tonnage of this cane is lower than newly planted cane.
Age therefore represents the number of years of regrowth before harvesting the cane.
The sugar cane cutting season usually begins in June and concludes in mid-November, the finishing date depending on how the season has gone with respect to rainfall and mill breakdowns. There may be some interaction between month of harvest and variety, as some varieties would be expected to give a higher sugar content at an earlier maturity level than others. Rainfall Monthy rainfall totals are given for each district from July 1996 through December 1997. July through October 1997. Note that November and December 1997 rainfall was not used because most cane has already been cut by this time.