When looking through the 1690 "Apple" images at Acclaim Images.com this A graft of apple tree stock to root stock. was a favorite.
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Description:
A graft of apple tree stock to root stock.
Stock photo of apple tree stock grafted to root stock.

Some related terms for more images:
propogation,  how to graft,  propagation,  orchards,  sylvestris,  malus,  growing,  rob walls,  cultivation,  cuttings,  apple tree graft,  grafting,  horticulture,