EFFECT OF BASE CATION ADDITION ON SOIL CHEMISTRY IN A SUGAR MAPLE FOREST OF THE LOWER LAURENTIANS, QUEBEC

Forest fertilization has been adopted as the primary means of controll ing sugar maple (Acer saccharum Marsh.) dieback in southern Quebec. Fo llowing foliar analysis, treatments containing appropriate mixtures of K, Ca, Mg, and (or) P have been used on commercial sugar groves. This study was undertaken to identify the impact of base cation additions on nutrient cycling in a sugar maple stand in the Lower Laurentians, Q uebec, and to quantify the amounts of added nutrients that were retain ed in the stand or lost by leaching. In 1988, six 40 x 40 m plots were established; three were kept as controls and the other three received a mixture of 500 kg-ha-1 of K2SO4, 250 kg.ha-1 of Ca,Mg(CO3)2 and 250 kg.ha-1 of CaCO3 applied as fine particulate matter in June 1989. Soi l solutions were collected weekly during the spring and fall from Octo ber 1988 until November 1992. Soil solution chemistry indicated that t here was increased biocycling of both K and Mg as a result of the trea tment. The application of appropriate mixtures of base cation will imp rove the fertility of the soils and decrease nutrient imbalances. The amount of added material lost from the rooting zone was a small propor tion of the amount added: over a 4-year period following treatment onl y 12.1, 9.5, and 1.4% of added Ca, Mg, and K were lost, respectively.