Effect of soil pH control by sulfur application to the turf surface of zoysiagrass on the emergence of annual bluegrass

Abstract

This study was conducted to evaluate the effects of the sulfur application rate and times on the emergence of annual bluegrass (Poa annuaL.) in Zoysiagrass (Zoysia matrellaMerr.) turf. The soil pH clearly decreased as the sulfur application rate increased, and a significant positive correlation was observed between the soil pH and drymatter production of annual bluegrass. The negative correlation was observed between the soil pH and exchange acidity, y₁. The inhibition of the emergence and growth of annual bluegrass may be caused by the elution of exchangeable Al induced by the reduced soil pH. From these results, it is suggested that annual bluegrass is controlled by maintaining soil pH of 0-1 cm underground of turf at about 4.7 with sulfur application on September in Kanto-area, Japan.