The eight genera in the family include the commercially important nut-producing trees walnut ( `` Juglans '' ) , pecan ( `` Carya illinoinensis '' ) , and hickory ( `` Carya '' ) .
There are eight genera in the family , including the commercially important nut-producing trees walnut ( Juglans ) , pecan ( Carya illinoinensis ) , and hickory ( Carya ) .