Quality enhancing pruning (see there), where pruning back to short shoots with relatively few eyes (buds) results in less grape hanging, i.e. a reduction in yield. With regard to shoot length or number of eyes, a distinction is made between tail, extensor and cone (see under arch). Which length is chosen depends on the vigour of the vines or the grape variety, as well as the environmental conditions with regard to climate and soil type. This is an important, but only one of the possible measures for lower or reduced yields. See also thinning out and leaf care, and a complete list of all measures under vineyard care.
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Thomas Götz
Weinberater, Weinblogger und Journalist; Schwendi