RT Journal Article SR Electronic T1 Treatment of Chlorotic Oaks and Red Maples by Soil Acidification JF Arboriculture & Urban Forestry (AUF) FD International Society of Arboriculture SP 122 OP 128 DO 10.48044/jauf.1984.023 VO 10 IS 4 A1 Steve Messenger YR 1984 UL http://auf.isa-arbor.com/content/10/4/122.abstract AB Rooting zone soil pHs and foliar nutrient imbalances were determined for chlorotic pin oaks, white oaks, and red maples. Soil pHs were significantly different between green and chlorotic tree sites of each species to a depth of 18-22 inches. Nutrient imbalances consisted of high phosphorus, potassium, and magnesium depending on season and species; and low manganese, iron, copper, and zinc depending on season and species. Abatement of chlorosis was accomplished by soil acidification with or without nutrient or mulch additions. Acidifications with sulfuric acid rapidly reduces the pH of alkaline soils to desired levels which may persist in treated subsoil zones for as long as four years.