Effect of simulated acid rain on physiology, growth and foliar nutrient concentrations of sugar maple

The effect of simulated acid rain (SAR) on sugar maple (Acer saccharum L.) growth and physiology following exposure to 12 weeks of controlled SAR treatment was investigated. SAR induced visible foliar injury in treatments more acidic than pH 3.5. Growth and gas exchange paramenters were not significantly altered by SAR treatment nor were goliar concentrations of K, Mg, Ca, Mn, P, Fe, or Al. Foliar levels of S were increased by treatment at pH 3.0. These results suggest that rainfalls less acidic than pH 3.5 are unlikely to cause significant direct effects to sugar maple.