Abstract
A field survey was initiated in the main sugarcane production areas of Puerto Rico to determine the pH status of sugarcane soils and those specific soil factors that influence growth and development, such as exchangeable cations, percentage base saturation (% BS) and lime requirement. Soil samples from Coloso, Plata, Arecibo, Humacao, Yabucoa and Eureka areas were analyzed for pH, available P, Fe and Mn; exchangeable K, Ca, Mg and Al; percentage base saturation and lime requirements. Soil pH ranged from as low as 3.2 to a high of 8.1. Sixty-eight percent of the soil samples analyzed showed pH values below 5.5. The lowest soil pH values were observed in the Eureka area and the highest in Arecibo, whereas in the Coloso, Plata, Humacao and Yabucoa areas pH values were intermediate with readings between 4 and 5 as an average. Eighty percent of the soil samples from Plata, 40.0% of those from Eureka and 40.5% of those from Coloso had pH values below 4.5. All soil samples collected in Humacao and Yabucoa (except one) showed pH values below 5.5. No definite trend was observed when sugarcane yield per acre and soil pH for the Yabucoa-Humacao area were compared. In general, P and K were low in all regions sampled, whereas Ca and Mg values were higher in the Coloso than in the Yabucoa-Humacao regions. Soils from the Coloso region showed higher levels of exchangeable Al and higher percentages of Al saturation than soils from the Yabucoa-Humacao region. This fact, together with a lower % BS should aggravate acidity problems in the Coloso region. Percentage base saturation was good at the higher pH readings.