Citrus shoots are characterized by flushes of length and sympodial type of growth. All leaves and thorns within a growth flush exhibit the same spirality, either dextral or sinistral. Secondary shoots from a given shoot have the opposite spirality from the parent shoot. Regularity of alternation of dextral and sinistral spirality in successive shoot growths is observed. Citrus thorns develop to the left of the petiole in shoots of sinistral spirality and to the right of the petiole in shoots of dextral spirality.