Sweet cherry rootstocks.

Abstract All commercial sweet cherry trees are either budded or grafted. This chapter deals with sweet cherry rootstocks. Rootstocks are used for several purposes: (i) ease for propagating and producing more trees of a superior cultivar; (ii) better adaptation to particular soil or site characteristics; and (iii) the potential improvement of production due to additional traits like precocious flowering, higher productivity, and greater or reduced scion vigor as appropriate. Unfortunately, no one rootstock can satisfy all the requirements for consistently producing high yields of large, firm fruit of premium quality. Growers are advised to consider carefully the effects of each specific scion-rootstock combination as a function of environmental and cultural practices when replanting an orchard. Selecting the proper rootstock depends not only on the management skills of the grower, but also on the scion cultivar, training system, and site climate and soil selected for the orchard. Dwarfing, semi-dwarfing and even semi-vigorous rootstocks have major economic advantages over full-size rootstocks. The development of these new, precocious rootstocks has been almost as significant to the sweet cherry industry as to the apple industry several decades ago. When compared to Mazzard, Colt and even Mahaleb, size-controlling rootstocks have allowed sweet cherry growers an opportunity to plant high density, pedestrian orchards that become profitable more quickly, are more readily protected with orchard covering systems, and promote greater labor efficiency, easier management, and a safer and more productive work environment.