ABSTRACT
The entire turfgrass industry in United States is conservatively estimated as being a $60 billion per year industry with a total area of more than 50 million acres, in which home lawns comprise about 65% and the remaining 35% include utility turf areas, golf courses, sports fi elds, and turf production (turfgrass seed and sod) areas [96]. Some of these managed turfgrass areas have unfavorable soil conditions such as high salinity and lower soil pH, particularly in the southeastern states and the northern boarder states between United States and Canada. In the world, approximately 50% of the arable soils is acidic with a pH of 5.0 or lower, at which the soil-soluble aluminum (Al) becomes a signifi cant limiting factor to plants [28,47,49].
