Acorn production in northern red oak stands in northwestern Pennsylvania. Forest Service research paper (Final)

Northern red oak acorn production was measured in 21 maturing stands on good sites in northwestern Pennsylvania. The number of acorns produced per acre varied from a low of 7,000 to nearly 273,000. Acorns were produced in all years. In no year was there consistently good acorn production at all areas, nor was there a good crop for more than two consecutive years at any location. Freezing temperatures when oaks were in flower was a major factor affecting acorn production on the Allegheny Plateau.