Eight categories of Quercus variabilis acorns after artificial cotyledon excision. Category I: excision of the base of both cotyledon (50%); Category II: excision of one cotyledon (50%); Category III: excision of apex of one cotyledon (25%); Category IV: excision of longitudinal 50% of one cotyledon (25%); Category V: excision of base of one cotyledon (25%); Category VI: excision of 50% of base of both cotyledon (25%); Category VII: excision of 50% of apex of one cotyledon (12.5%), and Category VIII: excision of 50% of base of one cotyledon (12.5%). (A color version of this figure is available at www.afsjournal.org.)