Food Reserves of Engelmann Spruce Planting Stock

Abstract Eight classes of three-yr-old Engelmann spruce planting stock were analyzed for carbohydrate, protein, lipid, and hemicellulose. The classes were: transplanted and undisturbed trees grown in the open or under 50 percent shade at two locations—a low-elevation nursery (ca. 7,000 ft) and a high-elevation holding bed (ca. 10,300 ft) where trees were held for 1 yr following transplanting from the nursery. Reserve foods and dry weights of trees grown solely in the nursery were also determined after 0, 2, and 4 mo storage. Transplanting reduced dry weight whether seedlings were transplanted in nursery or holding beds. Carbohydrates and hemicelluloses were similarly reduced by transplanting in the nursery, but lipid concentration was increased. Protein concentration was not affected. Dry weight and carbohydrate concentration were reduced by 4 mo storage, but proteins and lipids were not affected regardless of length of storage. Hemicellulose concentrations were highest following 2 mo storage. Survival of field-planted trees was not correlated with food reserves. However, survival may be adversely affected by carbohydrate concentrations below certain threshold levels when trees are planted. Forest Sci. 19:213-219.