Understanding Sucrose Metabolism and Growth in a Developing Sweetgum Plantation

Stem diameter growth of g-year-old sweetgum (Liquidambar styraciflua) trees was measured and related with the activity of sucrose-synthase (SS), an enzyme that has been associated with carbon sink strength in agriculture crops and tree seedlings. In 1984, 1-O sweetgum seedlings were transplanted to control plots and plots amended with sewage sludge or nitrogen and phosphorus fertilizer. After 8 growing seasons, trees on sludge contained four times as much volume as controls and twice as much volume as those on fertilized plots. In 1991, sludge treated soil had about 2 to 5 times as much in N and P as$soils from other treatments. There were no differences in the K levels between treatments.