Vegetative growth of young apple trees trained in vertical axis were studied with ‘Red Fuji',‘Jonagold’, ‘ Orin’ and ‘ Starkrimson’on M7, MM106, M26 interstocks in northern China. About 30branches sprouted from the central leader of the trees during the 4 years after planting for ‘Red Fuji’ and‘Jonagold’, and 26.7 and 20 branches respectively for ‘Orin' and ‘Starkrimson. Moreover the 2-year-old section of the central leader had the strongest capacity to sprout new branches (and sometimes the 1-year-old section too), and sprouted more new shoots than the other section. The total new shoots including spurs on the4-year-old trees reached 631 per tree for ‘ Jonagold', about 480 for ‘ Red Fuji’ and ‘ Orin’, and 312 for‘Starkrimson’. Percentage of spurs was about 61% for ‘Red Fuji’, 73% for ‘Jonagold’ and ‘Orin’, and81% for‘Starkrimson’. Growth vigor of the central leader and limbs of the young apple trees could quickly decline: the growth of the central leader decreased markedly in the fourth year after planting, and branches from the central leader grew vigorously only in the current growth season or in the first two years after branching.
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