2021 Carolina Geological Society Meeting and Field Trip – Updated June 29, 2021

Introduction

Viticulture, the art and science of wine-grape cultivation, is one of the fastest growing agricultural ventures in North Carolina, accounting for one of the state’s most important fruit crops and one of its riskiest.  The state now has 185 vineyard/wineries (ranking number 10 in the US) and an estimated additional 400 vineyards selling grapes to wineries and for table consumption.  The industry employs over 24,000 people directly or indirectly, produces approximately 2.4 million gallons of wine annually (ranking 7th in the nation) and generates an economic impact of around $4.7 billion.  In the 2021 CGS field excursion we will explore how geology and geomorphology play a critical role in determining the natural environment, or ‘terroir’, of three quite different, but adjacent, physiographic settings in western North Carolina in which wine-grapes are being cultivated.  The excursion will follow a transect from the inner Piedmont in Polk County, across the Blue Ridge escarpment in Polk and Henderson Counties, into the Blue Ridge plateau in Henderson and Buncombe Counties, all of which have active vineyard/winery operations that are producing excellent wines.

We will visit four operating vineyard/wineries along the excursion transect, and will offer an optional fifth vineyard at the end of the regularly scheduled trip:

Parker-Binns Vineyards, Polk County, Inner Piedmont

Marked Tree Vineyards, Henderson County, Blue Ridge escarpment

Burntshirt Vineyards, Henderson County, Blue Ridge escarpment and plateau

St. Paul Mountain Vineyards and Appalachian Ridge Cidery, Henderson County, Blue Ridge plateau

Biltmore Estate Winery/Vineyard, Buncombe County, Blue Ridge plateau

Burntshirt Vineyard, (Optional high-altitude vineyard at 3600’), Blue Ridge escarpment

At each vineyard stop the operators or winemakers will present short introductions to their operations and discuss the grapes they cultivate, the wines they produce, technologies utilized, and the strengths and weaknesses of their geographic locations.  This will be followed by a discussion of how the local geology and geomorphology play a role in the vineyards’ terroir, including such issues as bedrock, soils, slope, aspect, solar exposure, climate and weather, length of growing season, and other macro-, meso- and microclimate influences.  Importantly, participants will have the opportunity to sample each wineries’ products.

Field Trip Leaders and Topics to be Discussed

The excursion will be led by Joseph (“Joe”) Forrest, a retired petroleum exploration geologist and GIS/Remote Sensing consultant who lives in the Boston area.  In recent years Joe has assisted vineyard operators in North Carolina and Georgia in preparation of three successful American Viticultural Area petitions; He is presently working on additional areas in both the northern and southern Appalachians.  Joe will be joined by the following co-leaders/guidebook contributors:

John Havlin, Professor of Soil Sciences, NCSU Raleigh

Mark Hoffmann, Assistant Professor of Horticulture and Extension Specialist, NCSU Raleigh

Charles (“Chip”) Konrad, Professor of Climatology/Meteorology (Dept. of Geography), and Director of the Southeastern Regional Climate Center, UNC Chapel Hill

Philip Prince, Independent Consulting Geologist/Geomorphologist, Greenville, SC

Ian Taplin, Professor of Sociology and International Studies, Wake Forest University, Winston-Salem, NC

Rick Wooten, NC Geological Survey (Retired), Specialist in Geohazards & Engineering Geology, Asheville, NC

Bart Cattanach, NC Geological Survey, Project Leader, Blue Ridge Province Mapping

Topics to be discussed in detail by the excursion leaders will include the following: The meaning of “terroir” and the role of geology in the concept. ·Geography and origin of the three geomorphic regions of the excursion transect – Inner Piedmont, Blue Ridge escarpment and Blue Ridge plateau, with emphasis on the important role played by the Blue Ridge escarpment in differentiating environmentally distinct agricultural regions in the three counties.  ·Soil types and characteristics and how lithology and geomorphic processes determine their generation. ·Do soils, and by inference, rock types, really play a role in determining a wine’s taste and textural characteristics, or is this a marketing myth? ·Breaching of the Eastern Continental Divide, capture of the Broad River and origin and significance of the geomorphic feature referred to as the “Hendersonville bulge.” ·How the regions’ landforms control climate factors, such as temperature, precipitation, and length of growing season, and how these factors affect the types of grapes that can be sustainably cultivated. ·The nature of the infamous “Thermal Belt” of Polk and Rutherford Counties; Is it real and, if so, does the geomorphic setting really explain its origin. ·The idea of the American Viticultural Area, what it means and how geology plays a role in determining a region’s designation. ·Comparison of the excursion region’s terroir characteristics with those of other viticultural regions along the Blue Ridge escarpment and Eastern Continental Divide in North Carolina, South Carolina, and northern Georgia. ·Geohazards to viticulture in the excursion region.