Abstract Mathew LangePatricia Skinkis

First Year Effects of Vineyard Floor Management on Dry-Farmed Pinot noir Vine Performance in Different Soil Types

Mathew Lange and Patricia Skinkis*

*Oregon State University, 4017 Ag & Life Sci Bldg, 2750 SW Campus Way, Corvallis, OR, 97331 (patricia.skinkis@oregonstate.edu)

Vineyards in Oregon’s Willamette Valley are predominantly planted to perennial grass cover in alleyways for worker and equipment traction and to manage vine vegetative vigor. In dry seasons, spring tillage is implemented to reduce alleyway vegetation competition for available soil water. Previous research in the region shows impacts of till and no-till practices on vine vigor, primarily through altering vine nitrogen (N) status in a volcanic soil. More work is needed to understand the impacts on different soil types, as their physical properties influence water-holding capacity and nutrient concentrations, thereby affecting grapevine growth and productivity. The effects of vineyard floor management practices (till and no-till) were evaluated in one vineyard containing three distinct soil types derived from sedimentary, volcanic, and glacial deposit parent materials. Till and no-till treatments were applied to alleyways in a randomized complete block design with five to 10 field replicates of each soil type, within blocks of the same cultivar, rootstock, age, vine spacing, and training system. Vine growth, water stress, soil moisture, yield, vine nutrient status, and fruit compo­sition were measured. Vineyard floor management did not influence leaf stomatal conductance, stem water potential, or under-vine soil water content. However, vines in tilled treatments had higher leaf blade N concentrations and leaf greenness than no-till treatments in all soil types. While dormant pruning weights were not affected by higher tissue N, there was more berry N (yeast assimilable N) in the tilled treat­ments within the sedimentary soil only. The results indicate that vineyard floor man­agement had more influence on N availability within the soil rather than impacting undervine soil moisture or reducing vine water stress. These first-year results indicate that vineyard floor management practices have variable impacts based on soil type, and further research will determine longer-term impacts on vine growth and yield.

Funding Support: Oregon Wine Board, Erath Family Foundation