@inbook{ballard_1980, title={The means to excellence through nutrient amendment}, booktitle={Forest Plantations, the Shape of the Future: Proceedings of a symposium held at Tacoma, Washington, April 30-May 3, 1979}, publisher={Tacoma, Wash.: Weyerhaeuser Co.}, author={Ballard, R.}, year={1980}, pages={159} }