Term for gall-like, yellowish and two to four millimetre large growths in a bird's beak-like shape (nodose = nodular), which are induced on the young, still non-lignified roots by phylloxera infestation. Compared to the much more dangerous tuberosities (scab-like growths on old roots), they are generally relatively harmless. Nodosities are also formed in large numbers on most American species such as Vitis cinerea var. helleri (Vitis berlandieri), Vitis riparia and Vitis rupestris, but phylloxera infestation does not induce tuberosities there. As long as only nodosities are formed, the vine usually survives the phylloxera infestation relatively unscathed.
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Diplom-Sommelier, Weinakademiker und Weinberater, Volders (Österreich)