%0 Journal Article %A Michael V. Mckenry %T Grape Root Phenology Relative to Control of Parasitic Nematodes %D 1984 %R 10.5344/ajev.1984.35.4.206 %J American Journal of Enology and Viticulture %P 206-211 %V 35 %N 4 %X During a one-year period, portions of the root systems of 13 year-old grapevines were periodically excavated, screened from soil, sized, weighed and counted. Two periods of root initiation were evident; the first root flush occurred just prior to bloom, and the second just after harvest. Root flushes were of short duration. The spring flush provided approximately 2.7 root initials to each kg of moist soil, or 30 000 new roots per vine. Subsequent data from seven vineyards indicated that roots flushing in spring averaged 13 mm in length, and most became desiccated and necrosed by mid-summer. Structural roots tended to elongate along zones of least resistance, including old root debris or fracture lines of soil. Salt Creek (Ramsey) rootstock provided root systems of larger size and diameter than did own-rooted Thompson Seedless. These data suggest that new strategies for delivery, placement and timing of nematode control agents are warranted. %U https://www.ajevonline.org/content/ajev/35/4/206.full.pdf