TY - JOUR T1 - A Study of Longevity of Graft Combinations in California Vineyards, with Special Interest in the Vinifera <span class="sc">x</span> Rupestris Hybrids JF - American Journal of Enology and Viticulture JO - Am J Enol Vitic. SP - 18 LP - 24 DO - 10.5344/ajev.1978.29.1.18 VL - 29 IS - 1 AU - L. A. Lider AU - N. L. Ferrari AU - K. W. Bowers Y1 - 1978/01/01 UR - http://www.ajevonline.org/content/29/1/18.abstract N2 - The rootstock cultivars used in phylloxerated vineyards of the coastal districts of California are limited essentially to Rupestris St. George and Ganzin 1. Over the years, the suitability of Ganzin 1 for those vineyards has been questioned because it is less tolerant of phylloxera than is Rupestris St. George.Extensive field trials were conducted with a selected group of rootstocks from 1935 to 1941 in California vineyards. Data gathering was terminated in 1953, although several of those old trials remain. Comparative data on the growth and productivity of six scion varieties on five rootstocks were obtained from six of those trials in 1974 and 1975, when the trials were 35 to 40 years old. Scions on the two vinifera x rupestris rootstocks Ganzin 1 and Couderc 1202 have, in vegetative growth and fruit yield, performed equal to or better than those on Rupestris St. George. Root examinations in 1975 confirmed phylloxera on the roots of the vinifera x rupestris hybrids. ER -