1. Eplee R. E. 1985. Control and application methodology development in support of the witchweed program. 1985 Annual Report. USDA-APHIS, Whiteville Methods Develop. Cent., Whiteville NC 28472.
2. A Rapid Method for Enumeration of Viable Seeds in Soil
3. Tyler sieve, VWR Sci. P.O. Box 3351, Seattle, WA 98124.
4. Letters following this symbol are a WSSA-approved computer code from Composite List of Weeds, Weed Sci. 32, Suppl. 2. Available from WSSA, 309 W. Clark St., Champaign, IL 61820.