Effect of Backfill Amendment on Growth of Red Maple
Timothy J. Smalley and Carleton B. Wood
Abstract: Balled-and-burlapped red maple (Acer rubrum) trees were planted in holes backfilled with 1) native soil, 2) 50:50 (v/v) aged pine bark: soil, 3) 50:50 (v/v) Mr. Natural Concentrated Landscape Media (CLM): soil, and 4) 100% CLM. The CLM is an improved, proprietary soil amendment composed of top soil, pine humus, granite sand, crushed granite, expanded shale, and composted poultry litter. The CLM: soil treatment increased fibrous root growth within the planting hole after five months but did not increase shoot growth. Aged pine bark induced nitrogen deficiency symptoms and reduced shoot growth during the first year. Shoot growth of the treatments did not differ after two years. The data support use of native soil in backfilling planting holes.