Seed production and dispersal: Commercial seed-bearing age begins at 20
years and is optimum from 30 to 60 years. Good crops of seed can be
expected every 2 to 3 years. A high percentage of seeds are sound, but
high seed losses occur due to consumption by birds, insects, and
rodents. Natural pollination failures often occur due to the lack of
pollinated trees in immediate vicinity [4,24]. Upon ripening, seeds are
dispersed by gravity, squirrels, and other rodents. [9,24].
Vegetative propagation: Stumps of young butternut trees and saplings
can sprout [4,32].
- 4. Brinkman, Kenneth A. 1974. Juglans L. walnut. In: Schopmeyer, C. S., ed. Seeds of woody plants in the United States. Agric. Handb. 450. Washington, DC: U.S. Department of Agriculture, Forest Service: 454-459. 
- 24. Rink, George. 1990. Juglans cinera L. Butternut. In: Burns, Russell M.; Honkala, Barbara H., technical coordinators. Silvics of North America. Vol. 2. Hardwoods. Agric. Handb. 654. Washington, DC: U.S. Department of Agriculture, Forest Service: 386-390. 
- 32. Ward, Jeffrey S.; Stephens, George R. 1989. Long-term effects of a 1932 surface fire on stand structure in a Connecticut mixed hardwood forest. In: Rink, George; Budelsky, Carl A., eds. Proceedings, 7th central hardwood conference; 1989 March 5-8; Carbondale, IL. Gen. Tech. Rep. NC-132. St. Paul, MN: U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station: 267-273. 
- 9. Fernald, Merritt Lyndon. 1950. Gray's manual of botany. [Corrections supplied by R. C. Rollins]. Portland, OR: Dioscorides Press. 1632 p. (Dudley, Theodore R., gen. ed.; Biosystematics, Floristic & Phylogeny Series; vol. 2) 
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