Terroir 2020 banner
IVES 9 IVES Conference Series 9 Thinner topsoil improves vine growth and fruit composition in Mid-Atlantic United States vineyards

Thinner topsoil improves vine growth and fruit composition in Mid-Atlantic United States vineyards

Abstract

Aim: The aim of this study was to investigate the impact of topsoil thickness on dormant pruning weights, cluster compactness, and fruit composition (°Brix, titratable acidity, pH) in the Mid-Atlantic of the United States. 

Methods and Results: An Albariño vineyard in Frederick County, Maryland was previously terraced, resulting in topsoil (A-horizon) thickness differences while other factors are constant (weather, vine spacing, training, cultivar/clone/rootstock). We surveyed topsoil thickness along two transects using a combination of hand dug pits and soil probes, determining “topsoil” based on soil color and structure. The topsoil thickness we surveyed ranged from 0 to 30 cm. For reference, the vineyard’s mapped soil series, Mt. Zion, has 13 to 15 cm of topsoil.

Each panel of six vines served as an experimental unit, and we sampled 29 panels total corresponding to the topsoil measurement locations in 2019. We collected dormant pruning weights as well as cluster compactness (berries per cm rachis) and fruit chemistry (pH, titratable acidity, and °Brix). Fruit from vines growing in thinner topsoil had significantly lower titratable acidity and higher °Brix (R= 0.24). The correlation between topsoil and fruit titratable acidity was particularly strong, with topsoil thickness explaining 66.1% of variation in titratable acidity. There was not a significant relationship between topsoil thickness and fruit pH, but vines in thinner topsoil exhibited looser clusters (R2 = 0.27) and lower pruning weights (R= 0.58). 

Conclusions: 

Preliminary results suggest that fruit from vines growing in thinner topsoil ripen earlier. Compared to vines growing in thicker topsoil, they had lower titratable acidity and higher °Brix. Thinner topsoil also resulted in lower dormant pruning weights which indicates smaller vines, and looser clusters which may help with disease pressure. Understanding topsoil’s contribution to vine growth and fruit composition will help inform decisions about vineyard site selection, soil management, harvest time, and the overall terroir of a site. 

Significance and Impact of the Study: The viticulture industry in the Mid-Atlantic United States is growing, but their ability to support high-quality wine grape production may be hindered by certain soil properties. Many Mid-Atlantic soils are highly fertile and have relatively high available water holding capacity. In combination with the Mid-Atlantic’s humid continental climate, these soil properties can provide excessive plant-available water and nutrients to grapevines. Such excesses often produce vigorous vegetative growth (i.e., vigor) and detrimentally impact fruit composition and potential wine quality. Topsoil management could be an approach for growers to influence hydrology and fertility of vineyard soil. Choosing sites with less topsoil and/or managing topsoil thickness may help growers optimize their fruit chemistry and potentially predict and/or influence fruit ripening. 

DOI:

Publication date: March 17, 2021

Issue: Terroir 2020

Type: Video

Authors

Jaclyn C. Fiola*, Ryan D. Stewart, Tony K. Wolf, and Greg K. Evanylo

School of Plant and Environmental Sciences, Virginia Tech, 185 Ag Quad Lane, Blacksburg, VA 24061

Contact the author

Keywords

Soil fertility, soil hydrology, soil management, Mid-Atlantic 

Tags

IVES Conference Series | Terroir 2020

Citation

Related articles…

Rootstock regulation of scion phenotypes: the relationship between rootstock parentage and petiole mineral concentration

Rootstocks not only provide tolerance to Phylloxera, but also ensure the supply of water and mineral nutrients to the whole plant. Rootstocks are an important way of adapting to environmental conditions while conserving the typical features of scion varieties. We can exploit the large diversity of rootstocks used worldwide to aid this adaptation. The aim of this study was to characterise rootstock regulation of scion mineral status and its relation with scion development.

Taking advantages of innovative chemometric tools to unveil vineyard ecosystem dynamics: look across volatile secondary metabolites

Sustainable viticulture and winemaking continue to represent huge challenges, where a better knowledge about the functional role of biodiversity in the vineyard ecosystems is required.

Recommended grapevine varieties for the vineyards zone Vrsac and trend meteorological elements

The aim of this paper was to analyze trends of the meteorological elements and determine suitability of growing grapevine cultivar in viticulture region.

Towards understanding the mechanisms of resistance to grapevine Flavescence dorée

Flavescence dorée (FD) is a very serious grapevine disease, classified as quarantine in europe, where it appeared in the middle of the last century. It is associated with the presence of phytoplasmas, transmitted in the vineyard by a leafhopper of american origin, scaphoideus titanus. FD causes severe wine production losses and often leads to plant death. There are currently no alternative solutions to insecticide treatments against the vector and uprooting diseased vines.

Identification of the agronomical and landscapes potentialities in “Côtes du Rhône” area (France)

“Côtes du Rhône”, like many other controlled appellation wine, represents high stakes in the economical, social cultural and historical domains. The scenery formed by vineyards reveals these cultural values. It offers by a pleasant and appealing environment for the inhabitants and the tourists. It is also a powerful marketing tool for the winemakers.