The regional Central Forest Nursery of the regional government of Castilla y León (Spain) has released grafted plants of 5 elite clones of Pinus pinea, a.k.a. Mediterranean stone pine for its big hardshelled seeds. Their edible kernels, the genuine Mediterranean pine nuts, are nowadays the most expensive nuts of the world due to their scarcity and dependence on collection from the wild.

Different grafting techniques and deployment strategies for improved genetic materials of stone pine, Pinus pinea, offer more landowners the possibility to consider the tree as a viable crop. The stone pine is an emblematic tree that produces Mediterranean pine nuts, the most expensive nuts in global markets due to their scarcity.