Intensifying citrus tree crops and modifying tree canopies: a brief review

High-density citrus orchards have proven benefits for productivity but canopy management using conventional practices becomes problematic after trees reach their allocated space. This paper reviews the literature on high-density planting of citrus to understand the motivation for crop intensification and the different strategies for manipulating tree size such as dwarfing rootstocks, dwarfing viroids, pruning and trellis training.